AWS IoT exemples utilisant SDK pour .NET (v4)

/// <summary>
/// Hello AWS IoT example.
/// </summary>
public class HelloIoT
{
    /// <summary>
    /// Main method to run the Hello IoT example.
    /// </summary>
    /// <param name="args">Command line arguments.</param>
    /// <returns>A Task object.</returns>
    public static async Task Main(string[] args)
    {
        var iotClient = new AmazonIoTClient();

        try
        {
            Console.WriteLine("Hello AWS IoT! Let's list your IoT Things:");
            Console.WriteLine(new string('-', 80));

            // Use pages of 10.
            var request = new ListThingsRequest()
            {
                MaxResults = 10
            };
            var response = await iotClient.ListThingsAsync(request);

            // Since there is not a built-in paginator, use the NextMarker to paginate.
            bool hasMoreResults = true;

            var things = new List<ThingAttribute>();
            while (hasMoreResults)
            {
                things.AddRange(response.Things);

                // If NextMarker is not null, there are more results. Get the next page of results.
                if (!String.IsNullOrEmpty(response.NextMarker))
                {
                    request.Marker = response.NextMarker;
                    response = await iotClient.ListThingsAsync(request);
                }
                else
                    hasMoreResults = false;
            }

            if (things is { Count: > 0 })
            {
                Console.WriteLine($"Found {things.Count} IoT Things:");
                foreach (var thing in things)
                {
                    Console.WriteLine($"- Thing Name: {thing.ThingName}");
                    Console.WriteLine($"  Thing ARN: {thing.ThingArn}");
                    Console.WriteLine($"  Thing Type: {thing.ThingTypeName ?? "No type specified"}");
                    Console.WriteLine($"  Version: {thing.Version}");

                    if (thing.Attributes?.Count > 0)
                    {
                        Console.WriteLine("  Attributes:");
                        foreach (var attr in thing.Attributes)
                        {
                            Console.WriteLine($"    {attr.Key}: {attr.Value}");
                        }
                    }
                    Console.WriteLine();
                }
            }
            else
            {
                Console.WriteLine("No IoT Things found in your account.");
                Console.WriteLine("You can create IoT Things using the IoT Basics scenario example.");
            }

            Console.WriteLine("Hello IoT completed successfully.");
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            Console.WriteLine($"Request throttled, please try again later: {ex.Message}");
        }
        catch (Exception ex)
        {
            Console.WriteLine($"Couldn't list Things. Here's why: {ex.Message}");
        }
    }
}

Exécutez un scénario interactif illustrant AWS IoT les fonctionnalités.

/// <summary>
/// Scenario class for AWS IoT basics.
/// </summary>
public class IoTBasics
{
    public static bool IsInteractive = true;
    public static IoTWrapper? Wrapper = null;
    public static IAmazonCloudFormation? CloudFormationClient = null;
    public static ILogger<IoTBasics> logger = null!;
    private static IoTWrapper _iotWrapper = null!;
    private static IAmazonCloudFormation _amazonCloudFormation = null!;
    private static ILogger<IoTBasics> _logger = null!;

    private static string _stackName = "IoTBasicsStack";
    private static string _stackResourcePath = "../../../../../../scenarios/basics/iot/iot_usecase/resources/cfn_template.yaml";

    /// <summary>
    /// Main method for the IoT Basics scenario.
    /// </summary>
    /// <param name="args">Command line arguments.</param>
    /// <returns>A Task object.</returns>
    public static async Task Main(string[] args)
    {
        // Set up dependency injection for the Amazon service.
        using var host = Host.CreateDefaultBuilder(args)
            .ConfigureServices((_, services) =>
                services.AddAWSService<IAmazonIoT>(new AWSOptions() { Region = RegionEndpoint.USEast1 })
                    .AddAWSService<IAmazonCloudFormation>()
                        .AddTransient<IoTWrapper>()
                        .AddLogging(builder => builder.AddConsole())
                        .AddSingleton<IAmazonIotData>(sp =>
                        {
                            var iotService = sp.GetRequiredService<IAmazonIoT>();
                            var request = new DescribeEndpointRequest
                            {
                                EndpointType = "iot:Data-ATS"
                            };
                            var response = iotService.DescribeEndpointAsync(request).Result;
                            return new AmazonIotDataClient($"https://{response.EndpointAddress}/");
                        })
            )
            .Build();

        logger = LoggerFactory.Create(builder => builder.AddConsole())
            .CreateLogger<IoTBasics>();

        Wrapper = host.Services.GetRequiredService<IoTWrapper>();
        CloudFormationClient = host.Services.GetRequiredService<IAmazonCloudFormation>();

        // Set the private fields for backwards compatibility
        _logger = logger;
        _iotWrapper = Wrapper;
        _amazonCloudFormation = CloudFormationClient;

        Console.WriteLine(new string('-', 80));
        Console.WriteLine("Welcome to the AWS IoT example scenario.");
        Console.WriteLine("This example program demonstrates various interactions with the AWS Internet of Things (IoT) Core service.");
        Console.WriteLine();
        if (IsInteractive)
        {
            Console.WriteLine("Press Enter to continue...");
            Console.ReadLine();
        }
        Console.WriteLine(new string('-', 80));

        try
        {
            await RunScenarioAsync();
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "There was a problem running the scenario.");
            Console.WriteLine($"\nAn error occurred: {ex.Message}");
        }

        Console.WriteLine(new string('-', 80));
        Console.WriteLine("The AWS IoT scenario has successfully completed.");
        Console.WriteLine(new string('-', 80));
    }

    /// <summary>
    /// Run the IoT Basics scenario.
    /// </summary>
    /// <returns>A Task object.</returns>
    public static async Task RunScenarioAsync()
    {
        // Use static properties if available, otherwise use private fields
        var iotWrapper = Wrapper ?? _iotWrapper;
        var cloudFormationClient = CloudFormationClient ?? _amazonCloudFormation;
        var scenarioLogger = logger ?? _logger;

        await RunScenarioInternalAsync(iotWrapper, cloudFormationClient, scenarioLogger);
    }

    /// <summary>
    /// Internal method to run the IoT Basics scenario with injected dependencies.
    /// </summary>
    /// <param name="iotWrapper">The IoT wrapper instance.</param>
    /// <param name="cloudFormationClient">The CloudFormation client instance.</param>
    /// <param name="scenarioLogger">The logger instance.</param>
    /// <returns>A Task object.</returns>
    private static async Task RunScenarioInternalAsync(IoTWrapper iotWrapper, IAmazonCloudFormation cloudFormationClient, ILogger<IoTBasics> scenarioLogger)
    {
        string thingName = $"iot-thing-{Guid.NewGuid():N}";
        string certificateArn = "";
        string certificateId = "";
        string ruleName = $"iotruledefault";
        string snsTopicArn = "";

        try
        {
            // Step 1: Create an AWS IoT Thing
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("1. Create an AWS IoT Thing.");
            Console.WriteLine("An AWS IoT Thing represents a virtual entity in the AWS IoT service that can be associated with a physical device.");
            Console.WriteLine();

            if (IsInteractive)
            {
                Console.Write("Enter Thing name: ");
                var userInput = Console.ReadLine();
                if (!string.IsNullOrEmpty(userInput))
                    thingName = userInput;
            }
            else
            {
                Console.WriteLine($"Using default Thing name: {thingName}");
            }

            var thingArn = await iotWrapper.CreateThingAsync(thingName);
            Console.WriteLine($"{thingName} was successfully created. The ARN value is {thingArn}");
            Console.WriteLine(new string('-', 80));

            // Step 1.1: List AWS IoT Things
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("2. List AWS IoT Things.");
            Console.WriteLine("Now let's list the IoT Things to see the Thing we just created.");
            Console.WriteLine();
            if (IsInteractive)
            {
                Console.WriteLine("Press Enter to continue...");
                Console.ReadLine();
            }

            var things = await iotWrapper.ListThingsAsync();
            Console.WriteLine($"Found {things.Count} IoT Things:");
            foreach (var thing in things.Take(10)) // Show first 10 things
            {
                Console.WriteLine($"Thing Name: {thing.ThingName}");
                Console.WriteLine($"Thing ARN: {thing.ThingArn}");
                if (thing.Attributes != null && thing.Attributes.Any())
                {
                    Console.WriteLine("Attributes:");
                    foreach (var attr in thing.Attributes)
                    {
                        Console.WriteLine($"  {attr.Key}: {attr.Value}");
                    }
                }
                Console.WriteLine("--------------");
            }
            Console.WriteLine();
            Console.WriteLine(new string('-', 80));

            // Step 2: Generate a Device Certificate
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("3. Generate a device certificate.");
            Console.WriteLine("A device certificate performs a role in securing the communication between devices (Things) and the AWS IoT platform.");
            Console.WriteLine();

            var createCert = "y";
            if (IsInteractive)
            {
                Console.Write($"Do you want to create a certificate for {thingName}? (y/n)");
                createCert = Console.ReadLine();
            }
            else
            {
                Console.WriteLine($"Creating certificate for {thingName}...");
            }

            if (createCert?.ToLower() == "y")
            {
                var certificateResult = await iotWrapper.CreateKeysAndCertificateAsync();
                if (certificateResult.HasValue)
                {
                    var (certArn, certPem, certId) = certificateResult.Value;
                    certificateArn = certArn;
                    certificateId = certId;

                    Console.WriteLine($"\nCertificate:");
                    // Show only first few lines of certificate for brevity
                    var lines = certPem.Split('\n');
                    for (int i = 0; i < Math.Min(lines.Length, 5); i++)
                    {
                        Console.WriteLine(lines[i]);
                    }
                    if (lines.Length > 5)
                    {
                        Console.WriteLine("...");
                    }

                    Console.WriteLine($"\nCertificate ARN:");
                    Console.WriteLine(certificateArn);

                    // Step 3: Attach the Certificate to the AWS IoT Thing
                    Console.WriteLine("Attach the certificate to the AWS IoT Thing.");
                    var attachResult = await iotWrapper.AttachThingPrincipalAsync(thingName, certificateArn);
                    if (attachResult)
                    {
                        Console.WriteLine("Certificate attached to Thing successfully.");
                    }
                    else
                    {
                        Console.WriteLine("Failed to attach certificate to Thing.");
                    }

                    Console.WriteLine("Thing Details:");
                    Console.WriteLine($"Thing Name: {thingName}");
                    Console.WriteLine($"Thing ARN: {thingArn}");
                }
                else
                {
                    Console.WriteLine("Failed to create certificate.");
                }
            }
            Console.WriteLine(new string('-', 80));

            // Step 4: Update an AWS IoT Thing with Attributes
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("4. Update an AWS IoT Thing with Attributes.");
            Console.WriteLine("IoT Thing attributes, represented as key-value pairs, offer a pivotal advantage in facilitating efficient data");
            Console.WriteLine("management and retrieval within the AWS IoT ecosystem.");
            Console.WriteLine();
            if (IsInteractive)
            {
                Console.WriteLine("Press Enter to continue...");
                Console.ReadLine();
            }

            var attributes = new Dictionary<string, string>
            {
                { "Location", "Seattle" },
                { "DeviceType", "Sensor" },
                { "Firmware", "1.2.3" }
            };

            await iotWrapper.UpdateThingAsync(thingName, attributes);
            Console.WriteLine("Thing attributes updated successfully.");
            Console.WriteLine(new string('-', 80));

            // Step 5: Return a unique endpoint specific to the Amazon Web Services account
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("5. Return a unique endpoint specific to the Amazon Web Services account.");
            Console.WriteLine();
            if (IsInteractive)
            {
                Console.WriteLine("Press Enter to continue...");
                Console.ReadLine();
            }

            var endpoint = await iotWrapper.DescribeEndpointAsync();
            if (endpoint != null)
            {
                var subdomain = endpoint.Split('.')[0];
                Console.WriteLine($"Extracted subdomain: {subdomain}");
                Console.WriteLine($"Full Endpoint URL: https://{endpoint}");
            }
            else
            {
                Console.WriteLine("Failed to retrieve endpoint.");
            }
            Console.WriteLine(new string('-', 80));

            // Step 6: List your AWS IoT certificates
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("6. List your AWS IoT certificates");
            if (IsInteractive)
            {
                Console.WriteLine("Press Enter to continue...");
                Console.ReadLine();
            }

            var certificates = await iotWrapper.ListCertificatesAsync();
            foreach (var cert in certificates.Take(5)) // Show first 5 certificates
            {
                Console.WriteLine($"Cert id: {cert.CertificateId}");
                Console.WriteLine($"Cert Arn: {cert.CertificateArn}");
            }
            Console.WriteLine();
            Console.WriteLine(new string('-', 80));

            // Step 7: Create an IoT shadow
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("7. Update an IoT shadow that refers to a digital representation or virtual twin of a physical IoT device");
            Console.WriteLine();
            if (IsInteractive)
            {
                Console.WriteLine("Press Enter to continue...");
                Console.ReadLine();
            }

            var shadowPayload = JsonSerializer.Serialize(new
            {
                state = new
                {
                    desired = new
                    {
                        temperature = 25,
                        humidity = 50
                    }
                }
            });

            await iotWrapper.UpdateThingShadowAsync(thingName, shadowPayload);
            Console.WriteLine("Thing Shadow updated successfully.");
            Console.WriteLine(new string('-', 80));

            // Step 8: Write out the state information, in JSON format
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("8. Write out the state information, in JSON format.");
            if (IsInteractive)
            {
                Console.WriteLine("Press Enter to continue...");
                Console.ReadLine();
            }

            var shadowData = await iotWrapper.GetThingShadowAsync(thingName);
            Console.WriteLine($"Received Shadow Data: {shadowData}");
            Console.WriteLine(new string('-', 80));

            // Step 9: Set up resources (SNS topic and IAM role) and create a rule
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("9. Set up resources and create a rule");
            Console.WriteLine();

            // Deploy CloudFormation stack to create SNS topic and IAM role
            Console.WriteLine("Deploying CloudFormation stack to create SNS topic and IAM role...");

            var deployStack = !IsInteractive || GetYesNoResponse("Would you like to deploy the CloudFormation stack? (y/n) ");
            if (deployStack)
            {
                if (IsInteractive)
                {
                    Console.Write(
                        $"Enter stack resource file path (or press Enter for default '{_stackResourcePath}'): ");
                    var userResourcePath = Console.ReadLine();
                    if (!string.IsNullOrEmpty(userResourcePath))
                        _stackResourcePath = userResourcePath;
                }

                _stackName = PromptUserForStackName();

                var deploySuccess = await DeployCloudFormationStack(_stackName, cloudFormationClient, scenarioLogger);

                if (deploySuccess)
                {
                    // Get stack outputs
                    var stackOutputs = await GetStackOutputs(_stackName, cloudFormationClient, scenarioLogger);
                    if (stackOutputs != null)
                    {
                        snsTopicArn = stackOutputs["SNSTopicArn"];
                        string roleArn = stackOutputs["RoleArn"];

                        Console.WriteLine($"Successfully deployed stack. SNS topic: {snsTopicArn}");
                        Console.WriteLine($"Successfully deployed stack. IAM role: {roleArn}");

                        if (IsInteractive)
                        {
                            Console.Write($"Enter Rule name (press Enter for default '{ruleName}'): ");
                            var userRuleName = Console.ReadLine();
                            if (!string.IsNullOrEmpty(userRuleName))
                                ruleName = userRuleName;
                        }
                        else
                        {
                            Console.WriteLine($"Using default rule name: {ruleName}");
                        }

                        // Now create the IoT rule with the CloudFormation outputs
                        var ruleResult = await iotWrapper.CreateTopicRuleAsync(ruleName, snsTopicArn, roleArn);
                        if (ruleResult)
                        {
                            Console.WriteLine("IoT Rule created successfully.");
                        }
                        else
                        {
                            Console.WriteLine("Failed to create IoT rule.");
                        }
                    }
                    else
                    {
                        Console.WriteLine("Failed to get stack outputs. Skipping rule creation.");
                    }
                }
                else
                {
                    Console.WriteLine("Failed to deploy CloudFormation stack. Skipping rule creation.");
                }
            }
            else
            {
                Console.WriteLine("Skipping CloudFormation stack deployment and rule creation.");
            }
            Console.WriteLine(new string('-', 80));

            // Step 10: List your rules
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("10. List your rules.");
            if (IsInteractive)
            {
                Console.WriteLine("Press Enter to continue...");
                Console.ReadLine();
            }

            var rules = await iotWrapper.ListTopicRulesAsync();
            Console.WriteLine("List of IoT Rules:");
            foreach (var rule in rules.Take(5)) // Show first 5 rules
            {
                Console.WriteLine($"Rule Name: {rule.RuleName}");
                Console.WriteLine($"Rule ARN: {rule.RuleArn}");
                Console.WriteLine("--------------");
            }
            Console.WriteLine();
            Console.WriteLine(new string('-', 80));

            // Step 11: Search things using the Thing name
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("11. Search things using the Thing name.");
            if (IsInteractive)
            {
                Console.WriteLine("Press Enter to continue...");
                Console.ReadLine();
            }

            var searchResults = await iotWrapper.SearchIndexAsync($"thingName:{thingName}");
            if (searchResults.Any())
            {
                Console.WriteLine($"Thing id found using search is {searchResults.First().ThingId}");
            }
            else
            {
                Console.WriteLine($"No search results found for Thing: {thingName}");
            }
            Console.WriteLine(new string('-', 80));

            // Step 12: Cleanup - Detach and delete certificate
            if (!string.IsNullOrEmpty(certificateArn))
            {
                Console.WriteLine(new string('-', 80));
                var deleteCert = "y";
                if (IsInteractive)
                {
                    Console.Write($"Do you want to detach and delete the certificate for {thingName}? (y/n)");
                    deleteCert = Console.ReadLine();
                }
                else
                {
                    Console.WriteLine($"Detaching and deleting certificate for {thingName}...");
                }

                if (deleteCert?.ToLower() == "y")
                {
                    Console.WriteLine("12. You selected to detach and delete the certificate.");
                    if (IsInteractive)
                    {
                        Console.WriteLine("Press Enter to continue...");
                        Console.ReadLine();
                    }

                    await iotWrapper.DetachThingPrincipalAsync(thingName, certificateArn);
                    Console.WriteLine($"{certificateArn} was successfully removed from {thingName}");

                    await iotWrapper.DeleteCertificateAsync(certificateId);
                    Console.WriteLine($"{certificateArn} was successfully deleted.");
                }
                Console.WriteLine(new string('-', 80));
            }

            // Step 13: Delete the AWS IoT Thing
            Console.WriteLine(new string('-', 80));
            Console.WriteLine("13. Delete the AWS IoT Thing.");
            var deleteThing = "y";
            if (IsInteractive)
            {
                Console.Write($"Do you want to delete the IoT Thing? (y/n)");
                deleteThing = Console.ReadLine();
            }
            else
            {
                Console.WriteLine($"Deleting IoT Thing {thingName}...");
            }

            if (deleteThing?.ToLower() == "y")
            {
                await iotWrapper.DeleteThingAsync(thingName);
                Console.WriteLine($"Deleted Thing {thingName}");
            }
            Console.WriteLine(new string('-', 80));

            // Step 14: Clean up CloudFormation stack
            if (!string.IsNullOrEmpty(snsTopicArn))
            {
                Console.WriteLine(new string('-', 80));
                Console.WriteLine("14. Clean up CloudFormation stack.");
                Console.WriteLine("Deleting the CloudFormation stack and all resources...");

                var cleanup = !IsInteractive || GetYesNoResponse("Do you want to delete the CloudFormation stack and all resources? (y/n) ");
                if (cleanup)
                {
                    var ruleCleanupSuccess = await iotWrapper.DeleteTopicRuleAsync(ruleName);

                    var stackCleanupSuccess = await DeleteCloudFormationStack(_stackName, cloudFormationClient, scenarioLogger);
                    if (ruleCleanupSuccess && stackCleanupSuccess)
                    {
                        Console.WriteLine("Successfully cleaned up CloudFormation stack and all resources.");
                    }
                    else
                    {
                        Console.WriteLine("Some cleanup operations failed. Check the logs for details.");
                    }
                }
                else
                {
                    Console.WriteLine($"Resources will remain. Stack name: {_stackName}");
                }
                Console.WriteLine(new string('-', 80));
            }
        }
        catch (Exception ex)
        {
            scenarioLogger.LogError(ex, "Error occurred during scenario execution.");

            // Cleanup on error
            if (!string.IsNullOrEmpty(certificateArn) && !string.IsNullOrEmpty(thingName))
            {
                try
                {
                    await iotWrapper.DetachThingPrincipalAsync(thingName, certificateArn);
                    await iotWrapper.DeleteCertificateAsync(certificateId);
                }
                catch (Exception cleanupEx)
                {
                    scenarioLogger.LogError(cleanupEx, "Error during cleanup.");
                }
            }

            if (!string.IsNullOrEmpty(thingName))
            {
                try
                {
                    await iotWrapper.DeleteThingAsync(thingName);
                }
                catch (Exception cleanupEx)
                {
                    scenarioLogger.LogError(cleanupEx, "Error during Thing cleanup.");
                }
            }

            // Clean up CloudFormation stack on error
            if (!string.IsNullOrEmpty(snsTopicArn))
            {
                try
                {
                    await _iotWrapper.DeleteTopicRuleAsync(ruleName);
                    await DeleteCloudFormationStack(_stackName, cloudFormationClient, scenarioLogger);
                }
                catch (Exception cleanupEx)
                {
                    scenarioLogger.LogError(cleanupEx, "Error during CloudFormation stack cleanup.");
                }
            }

            throw;
        }
    }

    /// <summary>
    /// Deploys the CloudFormation stack with the necessary resources.
    /// </summary>
    /// <param name="stackName">The name of the CloudFormation stack.</param>
    /// <param name="cloudFormationClient">The CloudFormation client.</param>
    /// <param name="scenarioLogger">The logger.</param>
    /// <returns>True if the stack was deployed successfully.</returns>
    private static async Task<bool> DeployCloudFormationStack(string stackName, IAmazonCloudFormation cloudFormationClient, ILogger<IoTBasics> scenarioLogger)
    {
        Console.WriteLine($"\nDeploying CloudFormation stack: {stackName}");

        try
        {
            var request = new CreateStackRequest
            {
                StackName = stackName,
                TemplateBody = await File.ReadAllTextAsync(_stackResourcePath),
                Capabilities = new List<string> { Capability.CAPABILITY_NAMED_IAM }
            };

            var response = await cloudFormationClient.CreateStackAsync(request);

            if (response.HttpStatusCode == System.Net.HttpStatusCode.OK)
            {
                Console.WriteLine($"CloudFormation stack creation started: {stackName}");

                bool stackCreated = await WaitForStackCompletion(response.StackId, cloudFormationClient, scenarioLogger);

                if (stackCreated)
                {
                    Console.WriteLine("CloudFormation stack created successfully.");
                    return true;
                }
                else
                {
                    scenarioLogger.LogError($"CloudFormation stack creation failed: {stackName}");
                    return false;
                }
            }
            else
            {
                scenarioLogger.LogError($"Failed to create CloudFormation stack: {stackName}");
                return false;
            }
        }
        catch (AlreadyExistsException)
        {
            scenarioLogger.LogWarning($"CloudFormation stack '{stackName}' already exists. Please provide a unique name.");
            var newStackName = PromptUserForStackName();
            return await DeployCloudFormationStack(newStackName, cloudFormationClient, scenarioLogger);
        }
        catch (Exception ex)
        {
            scenarioLogger.LogError(ex, $"An error occurred while deploying the CloudFormation stack: {stackName}");
            return false;
        }
    }

    /// <summary>
    /// Waits for the CloudFormation stack to be in the CREATE_COMPLETE state.
    /// </summary>
    /// <param name="stackId">The ID of the CloudFormation stack.</param>
    /// <param name="cloudFormationClient">The CloudFormation client.</param>
    /// <param name="scenarioLogger">The logger.</param>
    /// <returns>True if the stack was created successfully.</returns>
    private static async Task<bool> WaitForStackCompletion(string stackId, IAmazonCloudFormation cloudFormationClient, ILogger<IoTBasics> scenarioLogger)
    {
        int retryCount = 0;
        const int maxRetries = 30;
        const int retryDelay = 10000;

        while (retryCount < maxRetries)
        {
            var describeStacksRequest = new DescribeStacksRequest
            {
                StackName = stackId
            };

            var describeStacksResponse = await cloudFormationClient.DescribeStacksAsync(describeStacksRequest);

            if (describeStacksResponse.Stacks.Count > 0)
            {
                if (describeStacksResponse.Stacks[0].StackStatus == StackStatus.CREATE_COMPLETE)
                {
                    return true;
                }
                if (describeStacksResponse.Stacks[0].StackStatus == StackStatus.CREATE_FAILED ||
                    describeStacksResponse.Stacks[0].StackStatus == StackStatus.ROLLBACK_COMPLETE)
                {
                    return false;
                }
            }

            Console.WriteLine("Waiting for CloudFormation stack creation to complete...");
            await Task.Delay(retryDelay);
            retryCount++;
        }

        scenarioLogger.LogError("Timed out waiting for CloudFormation stack creation to complete.");
        return false;
    }

    /// <summary>
    /// Gets the outputs from the CloudFormation stack.
    /// </summary>
    /// <param name="stackName">The name of the CloudFormation stack.</param>
    /// <param name="cloudFormationClient">The CloudFormation client.</param>
    /// <param name="scenarioLogger">The logger.</param>
    /// <returns>A dictionary of stack outputs.</returns>
    private static async Task<Dictionary<string, string>?> GetStackOutputs(string stackName, IAmazonCloudFormation cloudFormationClient, ILogger<IoTBasics> scenarioLogger)
    {
        try
        {
            var describeStacksRequest = new DescribeStacksRequest
            {
                StackName = stackName
            };

            var response = await cloudFormationClient.DescribeStacksAsync(describeStacksRequest);

            if (response.Stacks.Count > 0)
            {
                var outputs = new Dictionary<string, string>();
                foreach (var output in response.Stacks[0].Outputs)
                {
                    outputs[output.OutputKey] = output.OutputValue;
                }
                return outputs;
            }

            return null;
        }
        catch (Exception ex)
        {
            scenarioLogger.LogError(ex, $"Failed to get stack outputs for {stackName}");
            return null;
        }
    }

    /// <summary>
    /// Deletes the CloudFormation stack and waits for confirmation.
    /// </summary>
    /// <param name="stackName">The name of the CloudFormation stack.</param>
    /// <param name="cloudFormationClient">The CloudFormation client.</param>
    /// <param name="scenarioLogger">The logger.</param>
    /// <returns>True if the stack was deleted successfully.</returns>
    private static async Task<bool> DeleteCloudFormationStack(string stackName, IAmazonCloudFormation cloudFormationClient, ILogger<IoTBasics> scenarioLogger)
    {
        try
        {
            var request = new DeleteStackRequest
            {
                StackName = stackName
            };

            await cloudFormationClient.DeleteStackAsync(request);
            Console.WriteLine($"CloudFormation stack '{stackName}' is being deleted. This may take a few minutes.");

            bool stackDeleted = await WaitForStackDeletion(stackName, cloudFormationClient, scenarioLogger);

            if (stackDeleted)
            {
                Console.WriteLine($"CloudFormation stack '{stackName}' has been deleted.");
                return true;
            }
            else
            {
                scenarioLogger.LogError($"Failed to delete CloudFormation stack '{stackName}'.");
                return false;
            }
        }
        catch (Exception ex)
        {
            scenarioLogger.LogError(ex, $"An error occurred while deleting the CloudFormation stack: {stackName}");
            return false;
        }
    }

    /// <summary>
    /// Waits for the stack to be deleted.
    /// </summary>
    /// <param name="stackName">The name of the CloudFormation stack.</param>
    /// <param name="cloudFormationClient">The CloudFormation client.</param>
    /// <param name="scenarioLogger">The logger.</param>
    /// <returns>True if the stack was deleted successfully.</returns>
    private static async Task<bool> WaitForStackDeletion(string stackName, IAmazonCloudFormation cloudFormationClient, ILogger<IoTBasics> scenarioLogger)
    {
        int retryCount = 0;
        const int maxRetries = 30;
        const int retryDelay = 10000;

        while (retryCount < maxRetries)
        {
            var describeStacksRequest = new DescribeStacksRequest
            {
                StackName = stackName
            };

            try
            {
                var describeStacksResponse = await cloudFormationClient.DescribeStacksAsync(describeStacksRequest);

                if (describeStacksResponse.Stacks.Count == 0 ||
                    describeStacksResponse.Stacks[0].StackStatus == StackStatus.DELETE_COMPLETE)
                {
                    return true;
                }
            }
            catch (AmazonCloudFormationException ex) when (ex.ErrorCode == "ValidationError")
            {
                return true;
            }

            Console.WriteLine($"Waiting for CloudFormation stack '{stackName}' to be deleted...");
            await Task.Delay(retryDelay);
            retryCount++;
        }

        scenarioLogger.LogError($"Timed out waiting for CloudFormation stack '{stackName}' to be deleted.");
        return false;
    }

    /// <summary>
    /// Helper method to get a yes or no response from the user.
    /// </summary>
    private static bool GetYesNoResponse(string question)
    {
        Console.WriteLine(question);
        var ynResponse = Console.ReadLine();
        var response = ynResponse != null && ynResponse.Equals("y", StringComparison.InvariantCultureIgnoreCase);
        return response;
    }

    /// <summary>
    /// Prompts the user for a stack name.
    /// </summary>
    private static string PromptUserForStackName()
    {
        if (IsInteractive)
        {
            Console.Write($"Enter a name for the CloudFormation stack (press Enter for default '{_stackName}'): ");
            string? input = Console.ReadLine();
            if (!string.IsNullOrWhiteSpace(input))
            {
                var regex = new System.Text.RegularExpressions.Regex("[a-zA-Z][-a-zA-Z0-9]*");
                if (!regex.IsMatch(input))
                {
                    Console.WriteLine($"Invalid stack name. Using default: {_stackName}");
                    return _stackName;
                }
                return input;
            }
        }
        return _stackName;
    }
}

Une classe wrapper pour les méthodes du AWS IoT SDK.

/// <summary>
/// Wrapper methods to use Amazon IoT Core with .NET.
/// </summary>
public class IoTWrapper
{
    private readonly IAmazonIoT _amazonIoT;
    private readonly IAmazonIotData _amazonIotData;
    private readonly ILogger<IoTWrapper> _logger;

    /// <summary>
    /// Constructor for the IoT wrapper.
    /// </summary>
    /// <param name="amazonIoT">The injected IoT client.</param>
    /// <param name="amazonIotData">The injected IoT Data client.</param>
    /// <param name="logger">The injected logger.</param>
    public IoTWrapper(IAmazonIoT amazonIoT, IAmazonIotData amazonIotData, ILogger<IoTWrapper> logger)
    {
        _amazonIoT = amazonIoT;
        _amazonIotData = amazonIotData;
        _logger = logger;
    }

    /// <summary>
    /// Creates an AWS IoT Thing.
    /// </summary>
    /// <param name="thingName">The name of the Thing to create.</param>
    /// <returns>The ARN of the Thing created, or null if creation failed.</returns>
    public async Task<string?> CreateThingAsync(string thingName)
    {
        try
        {
            var request = new CreateThingRequest
            {
                ThingName = thingName
            };

            var response = await _amazonIoT.CreateThingAsync(request);
            _logger.LogInformation($"Created Thing {thingName} with ARN {response.ThingArn}");
            return response.ThingArn;
        }
        catch (Amazon.IoT.Model.ResourceAlreadyExistsException ex)
        {
            _logger.LogWarning($"Thing {thingName} already exists: {ex.Message}");
            return null;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't create Thing {thingName}. Here's why: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// Creates a device certificate for AWS IoT.
    /// </summary>
    /// <returns>The certificate details including ARN and certificate PEM, or null if creation failed.</returns>
    public async Task<(string CertificateArn, string CertificatePem, string CertificateId)?> CreateKeysAndCertificateAsync()
    {
        try
        {
            var request = new CreateKeysAndCertificateRequest
            {
                SetAsActive = true
            };

            var response = await _amazonIoT.CreateKeysAndCertificateAsync(request);
            _logger.LogInformation($"Created certificate with ARN {response.CertificateArn}");
            return (response.CertificateArn, response.CertificatePem, response.CertificateId);
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return null;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't create certificate. Here's why: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// Attaches a certificate to an IoT Thing.
    /// </summary>
    /// <param name="thingName">The name of the Thing.</param>
    /// <param name="certificateArn">The ARN of the certificate to attach.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> AttachThingPrincipalAsync(string thingName, string certificateArn)
    {
        try
        {
            var request = new AttachThingPrincipalRequest
            {
                ThingName = thingName,
                Principal = certificateArn
            };

            await _amazonIoT.AttachThingPrincipalAsync(request);
            _logger.LogInformation($"Attached certificate {certificateArn} to Thing {thingName}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot attach certificate - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't attach certificate to Thing. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Updates an IoT Thing with attributes.
    /// </summary>
    /// <param name="thingName">The name of the Thing to update.</param>
    /// <param name="attributes">Dictionary of attributes to add.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> UpdateThingAsync(string thingName, Dictionary<string, string> attributes)
    {
        try
        {
            var request = new UpdateThingRequest
            {
                ThingName = thingName,
                AttributePayload = new AttributePayload
                {
                    Attributes = attributes,
                    Merge = true
                }
            };

            await _amazonIoT.UpdateThingAsync(request);
            _logger.LogInformation($"Updated Thing {thingName} with attributes");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot update Thing - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't update Thing attributes. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Gets the AWS IoT endpoint URL.
    /// </summary>
    /// <returns>The endpoint URL, or null if retrieval failed.</returns>
    public async Task<string?> DescribeEndpointAsync()
    {
        try
        {
            var request = new DescribeEndpointRequest
            {
                EndpointType = "iot:Data-ATS"
            };

            var response = await _amazonIoT.DescribeEndpointAsync(request);
            _logger.LogInformation($"Retrieved endpoint: {response.EndpointAddress}");
            return response.EndpointAddress;
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return null;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't describe endpoint. Here's why: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// Lists all certificates associated with the account.
    /// </summary>
    /// <returns>List of certificate information, or empty list if listing failed.</returns>
    public async Task<List<Certificate>> ListCertificatesAsync()
    {
        try
        {
            var request = new ListCertificatesRequest();
            var response = await _amazonIoT.ListCertificatesAsync(request);

            _logger.LogInformation($"Retrieved {response.Certificates.Count} certificates");
            return response.Certificates;
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return new List<Certificate>();
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't list certificates. Here's why: {ex.Message}");
            return new List<Certificate>();
        }
    }

    /// <summary>
    /// Updates the Thing's shadow with new state information.
    /// </summary>
    /// <param name="thingName">The name of the Thing.</param>
    /// <param name="shadowPayload">The shadow payload in JSON format.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> UpdateThingShadowAsync(string thingName, string shadowPayload)
    {
        try
        {
            var request = new UpdateThingShadowRequest
            {
                ThingName = thingName,
                Payload = new MemoryStream(System.Text.Encoding.UTF8.GetBytes(shadowPayload))
            };

            await _amazonIotData.UpdateThingShadowAsync(request);
            _logger.LogInformation($"Updated shadow for Thing {thingName}");
            return true;
        }
        catch (Amazon.IotData.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot update Thing shadow - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't update Thing shadow. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Gets the Thing's shadow information.
    /// </summary>
    /// <param name="thingName">The name of the Thing.</param>
    /// <returns>The shadow data as a string, or null if retrieval failed.</returns>
    public async Task<string?> GetThingShadowAsync(string thingName)
    {
        try
        {
            var request = new GetThingShadowRequest
            {
                ThingName = thingName
            };

            var response = await _amazonIotData.GetThingShadowAsync(request);
            using var reader = new StreamReader(response.Payload);
            var shadowData = await reader.ReadToEndAsync();

            _logger.LogInformation($"Retrieved shadow for Thing {thingName}");
            return shadowData;
        }
        catch (Amazon.IotData.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot get Thing shadow - resource not found: {ex.Message}");
            return null;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't get Thing shadow. Here's why: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// Creates an IoT topic rule.
    /// </summary>
    /// <param name="ruleName">The name of the rule.</param>
    /// <param name="snsTopicArn">The ARN of the SNS topic for the action.</param>
    /// <param name="roleArn">The ARN of the IAM role.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> CreateTopicRuleAsync(string ruleName, string snsTopicArn, string roleArn)
    {
        try
        {
            var request = new CreateTopicRuleRequest
            {
                RuleName = ruleName,
                TopicRulePayload = new TopicRulePayload
                {
                    Sql = "SELECT * FROM 'topic/subtopic'",
                    Description = $"Rule created by .NET example: {ruleName}",
                    Actions = new List<Amazon.IoT.Model.Action>
                    {
                        new Amazon.IoT.Model.Action
                        {
                            Sns = new SnsAction
                            {
                                TargetArn = snsTopicArn,
                                RoleArn = roleArn
                            }
                        }
                    },
                    RuleDisabled = false
                }
            };

            await _amazonIoT.CreateTopicRuleAsync(request);
            _logger.LogInformation($"Created IoT rule {ruleName}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceAlreadyExistsException ex)
        {
            _logger.LogWarning($"Rule {ruleName} already exists: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't create topic rule. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Deletes an IoT topic rule.
    /// </summary>
    /// <param name="ruleName">The name of the rule.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> DeleteTopicRuleAsync(string ruleName)
    {
        try
        {
            var request = new DeleteTopicRuleRequest
            {
                RuleName = ruleName,
            };

            await _amazonIoT.DeleteTopicRuleAsync(request);
            _logger.LogInformation($"Deleted IoT rule {ruleName}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogWarning($"Rule {ruleName} not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't delete topic rule. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Lists all IoT topic rules.
    /// </summary>
    /// <returns>List of topic rules, or empty list if listing failed.</returns>
    public async Task<List<TopicRuleListItem>> ListTopicRulesAsync()
    {
        try
        {
            var request = new ListTopicRulesRequest();
            var response = await _amazonIoT.ListTopicRulesAsync(request);

            _logger.LogInformation($"Retrieved {response.Rules.Count} IoT rules");
            return response.Rules;
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return new List<TopicRuleListItem>();
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't list topic rules. Here's why: {ex.Message}");
            return new List<TopicRuleListItem>();
        }
    }

    /// <summary>
    /// Searches for IoT Things using the search index.
    /// </summary>
    /// <param name="queryString">The search query string.</param>
    /// <returns>List of Things that match the search criteria, or empty list if search failed.</returns>
    public async Task<List<ThingDocument>> SearchIndexAsync(string queryString)
    {
        try
        {
            // First, try to perform the search
            var request = new SearchIndexRequest
            {
                QueryString = queryString
            };

            var response = await _amazonIoT.SearchIndexAsync(request);
            _logger.LogInformation($"Search found {response.Things.Count} Things");
            return response.Things;
        }
        catch (Amazon.IoT.Model.IndexNotReadyException ex)
        {
            _logger.LogWarning($"Search index not ready, setting up indexing configuration: {ex.Message}");
            return await SetupIndexAndRetrySearchAsync(queryString);
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex) when (ex.Message.Contains("index") || ex.Message.Contains("Index"))
        {
            _logger.LogWarning($"Search index not configured, setting up indexing configuration: {ex.Message}");
            return await SetupIndexAndRetrySearchAsync(queryString);
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return new List<ThingDocument>();
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't search index. Here's why: {ex.Message}");
            return new List<ThingDocument>();
        }
    }

    /// <summary>
    /// Sets up the indexing configuration and retries the search after waiting for the index to be ready.
    /// </summary>
    /// <param name="queryString">The search query string.</param>
    /// <returns>List of Things that match the search criteria, or empty list if setup/search failed.</returns>
    private async Task<List<ThingDocument>> SetupIndexAndRetrySearchAsync(string queryString)
    {
        try
        {
            // Update indexing configuration to REGISTRY mode
            _logger.LogInformation("Setting up IoT search indexing configuration...");
            await _amazonIoT.UpdateIndexingConfigurationAsync(
                new UpdateIndexingConfigurationRequest()
                {
                    ThingIndexingConfiguration = new ThingIndexingConfiguration()
                    {
                        ThingIndexingMode = ThingIndexingMode.REGISTRY
                    }
                });

            _logger.LogInformation("Indexing configuration updated. Waiting for index to be ready...");

            // Wait for the index to be set up - this can take some time
            const int maxRetries = 10;
            const int retryDelaySeconds = 10;

            for (int attempt = 1; attempt <= maxRetries; attempt++)
            {
                try
                {
                    _logger.LogInformation($"Waiting for index to be ready (attempt {attempt}/{maxRetries})...");
                    await Task.Delay(TimeSpan.FromSeconds(retryDelaySeconds));

                    // Try to get the current indexing configuration to see if it's ready
                    var configResponse = await _amazonIoT.GetIndexingConfigurationAsync(new GetIndexingConfigurationRequest());
                    if (configResponse.ThingIndexingConfiguration?.ThingIndexingMode == ThingIndexingMode.REGISTRY)
                    {
                        // Try the search again
                        var request = new SearchIndexRequest
                        {
                            QueryString = queryString
                        };

                        var response = await _amazonIoT.SearchIndexAsync(request);
                        _logger.LogInformation($"Search found {response.Things.Count} Things after index setup");
                        return response.Things;
                    }
                }
                catch (Amazon.IoT.Model.IndexNotReadyException)
                {
                    // Index still not ready, continue waiting
                    _logger.LogInformation("Index still not ready, continuing to wait...");
                    continue;
                }
                catch (Amazon.IoT.Model.InvalidRequestException ex) when (ex.Message.Contains("index") || ex.Message.Contains("Index"))
                {
                    // Index still not ready, continue waiting
                    _logger.LogInformation("Index still not ready, continuing to wait...");
                    continue;
                }
            }

            _logger.LogWarning("Timeout waiting for search index to be ready after configuration update");
            return new List<ThingDocument>();
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't set up search index configuration. Here's why: {ex.Message}");
            return new List<ThingDocument>();
        }
    }

    /// <summary>
    /// Detaches a certificate from an IoT Thing.
    /// </summary>
    /// <param name="thingName">The name of the Thing.</param>
    /// <param name="certificateArn">The ARN of the certificate to detach.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> DetachThingPrincipalAsync(string thingName, string certificateArn)
    {
        try
        {
            var request = new DetachThingPrincipalRequest
            {
                ThingName = thingName,
                Principal = certificateArn
            };

            await _amazonIoT.DetachThingPrincipalAsync(request);
            _logger.LogInformation($"Detached certificate {certificateArn} from Thing {thingName}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot detach certificate - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't detach certificate from Thing. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Deletes an IoT certificate.
    /// </summary>
    /// <param name="certificateId">The ID of the certificate to delete.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> DeleteCertificateAsync(string certificateId)
    {
        try
        {
            // First, update the certificate to inactive state
            var updateRequest = new UpdateCertificateRequest
            {
                CertificateId = certificateId,
                NewStatus = CertificateStatus.INACTIVE
            };
            await _amazonIoT.UpdateCertificateAsync(updateRequest);

            // Then delete the certificate
            var deleteRequest = new DeleteCertificateRequest
            {
                CertificateId = certificateId
            };

            await _amazonIoT.DeleteCertificateAsync(deleteRequest);
            _logger.LogInformation($"Deleted certificate {certificateId}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot delete certificate - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't delete certificate. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Deletes an IoT Thing.
    /// </summary>
    /// <param name="thingName">The name of the Thing to delete.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> DeleteThingAsync(string thingName)
    {
        try
        {
            var request = new DeleteThingRequest
            {
                ThingName = thingName
            };

            await _amazonIoT.DeleteThingAsync(request);
            _logger.LogInformation($"Deleted Thing {thingName}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot delete Thing - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't delete Thing. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Lists IoT Things with pagination support.
    /// </summary>
    /// <returns>List of Things, or empty list if listing failed.</returns>
    public async Task<List<ThingAttribute>> ListThingsAsync()
    {
        try
        {
            // Use pages of 10.
            var request = new ListThingsRequest()
            {
                MaxResults = 10
            };
            var response = await _amazonIoT.ListThingsAsync(request);

            // Since there is not a built-in paginator, use the NextMarker to paginate.
            bool hasMoreResults = true;

            var things = new List<ThingAttribute>();
            while (hasMoreResults)
            {
                things.AddRange(response.Things);

                // If NextMarker is not null, there are more results. Get the next page of results.
                if (!String.IsNullOrEmpty(response.NextMarker))
                {
                    request.Marker = response.NextMarker;
                    response = await _amazonIoT.ListThingsAsync(request);
                }
                else
                    hasMoreResults = false;
            }

            _logger.LogInformation($"Retrieved {things.Count} Things");
            return things;
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return new List<ThingAttribute>();
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't list Things. Here's why: {ex.Message}");
            return new List<ThingAttribute>();
        }
    }

}

    /// <summary>
    /// Attaches a certificate to an IoT Thing.
    /// </summary>
    /// <param name="thingName">The name of the Thing.</param>
    /// <param name="certificateArn">The ARN of the certificate to attach.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> AttachThingPrincipalAsync(string thingName, string certificateArn)
    {
        try
        {
            var request = new AttachThingPrincipalRequest
            {
                ThingName = thingName,
                Principal = certificateArn
            };

            await _amazonIoT.AttachThingPrincipalAsync(request);
            _logger.LogInformation($"Attached certificate {certificateArn} to Thing {thingName}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot attach certificate - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't attach certificate to Thing. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Creates a device certificate for AWS IoT.
    /// </summary>
    /// <returns>The certificate details including ARN and certificate PEM, or null if creation failed.</returns>
    public async Task<(string CertificateArn, string CertificatePem, string CertificateId)?> CreateKeysAndCertificateAsync()
    {
        try
        {
            var request = new CreateKeysAndCertificateRequest
            {
                SetAsActive = true
            };

            var response = await _amazonIoT.CreateKeysAndCertificateAsync(request);
            _logger.LogInformation($"Created certificate with ARN {response.CertificateArn}");
            return (response.CertificateArn, response.CertificatePem, response.CertificateId);
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return null;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't create certificate. Here's why: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// Creates an AWS IoT Thing.
    /// </summary>
    /// <param name="thingName">The name of the Thing to create.</param>
    /// <returns>The ARN of the Thing created, or null if creation failed.</returns>
    public async Task<string?> CreateThingAsync(string thingName)
    {
        try
        {
            var request = new CreateThingRequest
            {
                ThingName = thingName
            };

            var response = await _amazonIoT.CreateThingAsync(request);
            _logger.LogInformation($"Created Thing {thingName} with ARN {response.ThingArn}");
            return response.ThingArn;
        }
        catch (Amazon.IoT.Model.ResourceAlreadyExistsException ex)
        {
            _logger.LogWarning($"Thing {thingName} already exists: {ex.Message}");
            return null;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't create Thing {thingName}. Here's why: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// Creates an IoT topic rule.
    /// </summary>
    /// <param name="ruleName">The name of the rule.</param>
    /// <param name="snsTopicArn">The ARN of the SNS topic for the action.</param>
    /// <param name="roleArn">The ARN of the IAM role.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> CreateTopicRuleAsync(string ruleName, string snsTopicArn, string roleArn)
    {
        try
        {
            var request = new CreateTopicRuleRequest
            {
                RuleName = ruleName,
                TopicRulePayload = new TopicRulePayload
                {
                    Sql = "SELECT * FROM 'topic/subtopic'",
                    Description = $"Rule created by .NET example: {ruleName}",
                    Actions = new List<Amazon.IoT.Model.Action>
                    {
                        new Amazon.IoT.Model.Action
                        {
                            Sns = new SnsAction
                            {
                                TargetArn = snsTopicArn,
                                RoleArn = roleArn
                            }
                        }
                    },
                    RuleDisabled = false
                }
            };

            await _amazonIoT.CreateTopicRuleAsync(request);
            _logger.LogInformation($"Created IoT rule {ruleName}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceAlreadyExistsException ex)
        {
            _logger.LogWarning($"Rule {ruleName} already exists: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't create topic rule. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Deletes an IoT certificate.
    /// </summary>
    /// <param name="certificateId">The ID of the certificate to delete.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> DeleteCertificateAsync(string certificateId)
    {
        try
        {
            // First, update the certificate to inactive state
            var updateRequest = new UpdateCertificateRequest
            {
                CertificateId = certificateId,
                NewStatus = CertificateStatus.INACTIVE
            };
            await _amazonIoT.UpdateCertificateAsync(updateRequest);

            // Then delete the certificate
            var deleteRequest = new DeleteCertificateRequest
            {
                CertificateId = certificateId
            };

            await _amazonIoT.DeleteCertificateAsync(deleteRequest);
            _logger.LogInformation($"Deleted certificate {certificateId}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot delete certificate - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't delete certificate. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Deletes an IoT Thing.
    /// </summary>
    /// <param name="thingName">The name of the Thing to delete.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> DeleteThingAsync(string thingName)
    {
        try
        {
            var request = new DeleteThingRequest
            {
                ThingName = thingName
            };

            await _amazonIoT.DeleteThingAsync(request);
            _logger.LogInformation($"Deleted Thing {thingName}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot delete Thing - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't delete Thing. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Gets the AWS IoT endpoint URL.
    /// </summary>
    /// <returns>The endpoint URL, or null if retrieval failed.</returns>
    public async Task<string?> DescribeEndpointAsync()
    {
        try
        {
            var request = new DescribeEndpointRequest
            {
                EndpointType = "iot:Data-ATS"
            };

            var response = await _amazonIoT.DescribeEndpointAsync(request);
            _logger.LogInformation($"Retrieved endpoint: {response.EndpointAddress}");
            return response.EndpointAddress;
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return null;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't describe endpoint. Here's why: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// Detaches a certificate from an IoT Thing.
    /// </summary>
    /// <param name="thingName">The name of the Thing.</param>
    /// <param name="certificateArn">The ARN of the certificate to detach.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> DetachThingPrincipalAsync(string thingName, string certificateArn)
    {
        try
        {
            var request = new DetachThingPrincipalRequest
            {
                ThingName = thingName,
                Principal = certificateArn
            };

            await _amazonIoT.DetachThingPrincipalAsync(request);
            _logger.LogInformation($"Detached certificate {certificateArn} from Thing {thingName}");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot detach certificate - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't detach certificate from Thing. Here's why: {ex.Message}");
            return false;
        }
    }

    /// <summary>
    /// Lists all certificates associated with the account.
    /// </summary>
    /// <returns>List of certificate information, or empty list if listing failed.</returns>
    public async Task<List<Certificate>> ListCertificatesAsync()
    {
        try
        {
            var request = new ListCertificatesRequest();
            var response = await _amazonIoT.ListCertificatesAsync(request);

            _logger.LogInformation($"Retrieved {response.Certificates.Count} certificates");
            return response.Certificates;
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return new List<Certificate>();
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't list certificates. Here's why: {ex.Message}");
            return new List<Certificate>();
        }
    }

    /// <summary>
    /// Lists IoT Things with pagination support.
    /// </summary>
    /// <returns>List of Things, or empty list if listing failed.</returns>
    public async Task<List<ThingAttribute>> ListThingsAsync()
    {
        try
        {
            // Use pages of 10.
            var request = new ListThingsRequest()
            {
                MaxResults = 10
            };
            var response = await _amazonIoT.ListThingsAsync(request);

            // Since there is not a built-in paginator, use the NextMarker to paginate.
            bool hasMoreResults = true;

            var things = new List<ThingAttribute>();
            while (hasMoreResults)
            {
                things.AddRange(response.Things);

                // If NextMarker is not null, there are more results. Get the next page of results.
                if (!String.IsNullOrEmpty(response.NextMarker))
                {
                    request.Marker = response.NextMarker;
                    response = await _amazonIoT.ListThingsAsync(request);
                }
                else
                    hasMoreResults = false;
            }

            _logger.LogInformation($"Retrieved {things.Count} Things");
            return things;
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return new List<ThingAttribute>();
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't list Things. Here's why: {ex.Message}");
            return new List<ThingAttribute>();
        }
    }

    /// <summary>
    /// Searches for IoT Things using the search index.
    /// </summary>
    /// <param name="queryString">The search query string.</param>
    /// <returns>List of Things that match the search criteria, or empty list if search failed.</returns>
    public async Task<List<ThingDocument>> SearchIndexAsync(string queryString)
    {
        try
        {
            // First, try to perform the search
            var request = new SearchIndexRequest
            {
                QueryString = queryString
            };

            var response = await _amazonIoT.SearchIndexAsync(request);
            _logger.LogInformation($"Search found {response.Things.Count} Things");
            return response.Things;
        }
        catch (Amazon.IoT.Model.IndexNotReadyException ex)
        {
            _logger.LogWarning($"Search index not ready, setting up indexing configuration: {ex.Message}");
            return await SetupIndexAndRetrySearchAsync(queryString);
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex) when (ex.Message.Contains("index") || ex.Message.Contains("Index"))
        {
            _logger.LogWarning($"Search index not configured, setting up indexing configuration: {ex.Message}");
            return await SetupIndexAndRetrySearchAsync(queryString);
        }
        catch (Amazon.IoT.Model.ThrottlingException ex)
        {
            _logger.LogWarning($"Request throttled, please try again later: {ex.Message}");
            return new List<ThingDocument>();
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't search index. Here's why: {ex.Message}");
            return new List<ThingDocument>();
        }
    }

    /// <summary>
    /// Sets up the indexing configuration and retries the search after waiting for the index to be ready.
    /// </summary>
    /// <param name="queryString">The search query string.</param>
    /// <returns>List of Things that match the search criteria, or empty list if setup/search failed.</returns>
    private async Task<List<ThingDocument>> SetupIndexAndRetrySearchAsync(string queryString)
    {
        try
        {
            // Update indexing configuration to REGISTRY mode
            _logger.LogInformation("Setting up IoT search indexing configuration...");
            await _amazonIoT.UpdateIndexingConfigurationAsync(
                new UpdateIndexingConfigurationRequest()
                {
                    ThingIndexingConfiguration = new ThingIndexingConfiguration()
                    {
                        ThingIndexingMode = ThingIndexingMode.REGISTRY
                    }
                });

            _logger.LogInformation("Indexing configuration updated. Waiting for index to be ready...");

            // Wait for the index to be set up - this can take some time
            const int maxRetries = 10;
            const int retryDelaySeconds = 10;

            for (int attempt = 1; attempt <= maxRetries; attempt++)
            {
                try
                {
                    _logger.LogInformation($"Waiting for index to be ready (attempt {attempt}/{maxRetries})...");
                    await Task.Delay(TimeSpan.FromSeconds(retryDelaySeconds));

                    // Try to get the current indexing configuration to see if it's ready
                    var configResponse = await _amazonIoT.GetIndexingConfigurationAsync(new GetIndexingConfigurationRequest());
                    if (configResponse.ThingIndexingConfiguration?.ThingIndexingMode == ThingIndexingMode.REGISTRY)
                    {
                        // Try the search again
                        var request = new SearchIndexRequest
                        {
                            QueryString = queryString
                        };

                        var response = await _amazonIoT.SearchIndexAsync(request);
                        _logger.LogInformation($"Search found {response.Things.Count} Things after index setup");
                        return response.Things;
                    }
                }
                catch (Amazon.IoT.Model.IndexNotReadyException)
                {
                    // Index still not ready, continue waiting
                    _logger.LogInformation("Index still not ready, continuing to wait...");
                    continue;
                }
                catch (Amazon.IoT.Model.InvalidRequestException ex) when (ex.Message.Contains("index") || ex.Message.Contains("Index"))
                {
                    // Index still not ready, continue waiting
                    _logger.LogInformation("Index still not ready, continuing to wait...");
                    continue;
                }
            }

            _logger.LogWarning("Timeout waiting for search index to be ready after configuration update");
            return new List<ThingDocument>();
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't set up search index configuration. Here's why: {ex.Message}");
            return new List<ThingDocument>();
        }
    }

    /// <summary>
    /// Updates an IoT Thing with attributes.
    /// </summary>
    /// <param name="thingName">The name of the Thing to update.</param>
    /// <param name="attributes">Dictionary of attributes to add.</param>
    /// <returns>True if successful, false otherwise.</returns>
    public async Task<bool> UpdateThingAsync(string thingName, Dictionary<string, string> attributes)
    {
        try
        {
            var request = new UpdateThingRequest
            {
                ThingName = thingName,
                AttributePayload = new AttributePayload
                {
                    Attributes = attributes,
                    Merge = true
                }
            };

            await _amazonIoT.UpdateThingAsync(request);
            _logger.LogInformation($"Updated Thing {thingName} with attributes");
            return true;
        }
        catch (Amazon.IoT.Model.ResourceNotFoundException ex)
        {
            _logger.LogError($"Cannot update Thing - resource not found: {ex.Message}");
            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError($"Couldn't update Thing attributes. Here's why: {ex.Message}");
            return false;
        }
    }