# Monitor your serverless application with AWS SAM Monitor your application After deploying your serverless application, you can monitor it to provide insights on its operations and detect anomalies, which can help with troubleshooting. This section provides details on monitoring your serverless application. This includes information on how to configure Amazon CloudWatch to notify you when it detects anomalies. It also provides information on working with logs, including error highlighting and tips for viewing, filtering, fetching, and tailing logs. **Topics** + [ # Using CloudWatch Application Insights to monitor your AWS SAM serverless applications ](monitor-app-insights.md) + [ # Working with logs in AWS SAM ](serverless-sam-cli-logging.md) # Using CloudWatch Application Insights to monitor your AWS SAM serverless applications Application Insights Amazon CloudWatch Application Insights helps you monitor the AWS resources in your applications to help identify potential issues. It can analyze AWS resource data for signs of problems and build automated dashboards to visualize them. You can configure CloudWatch Application Insights to use with your AWS Serverless Application Model (AWS SAM) applications. To learn more about CloudWatch Application Insights, see [Amazon CloudWatch Application Insights](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch-application-insights.html) in the *Amazon CloudWatch User Guide*. **Topics** + [ ## Configuring CloudWatch Application Insights with AWS SAM ](#monitor-app-insights-configure) + [ ## Next steps ](#monitor-app-insights-next) ## Configuring CloudWatch Application Insights with AWS SAM Configure CloudWatch Application Insights for your AWS SAM applications through the AWS SAM Command Line Interface (AWS SAM CLI) or through your AWS SAM templates. ### Configure through the AWS SAM CLI When initializing your application with **sam init**, activate CloudWatch Application Insights through the interactive flow or by using the **--application-insights** option. To activate CloudWatch Application Insights through the AWS SAM CLI interactive flow, enter **y** when prompted. ``` Would you like to enable monitoring using CloudWatch Application Insights? For more info, please view https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch-application-insights.html [y/N]: ``` To activate CloudWatch Application Insights with the **--application-insights** option, do the following. ``` sam init --application-insights ``` To learn more about using the **sam init** command, see [sam init](sam-cli-command-reference-sam-init.md). ### Configure through AWS SAM templates Activate CloudWatch Application Insights by defining the `AWS::ResourceGroups::Group` and `AWS::ApplicationInsights::Application` resources in your AWS SAM templates. ``` AWSTemplateFormatVersion: '2010-09-09' Transform: AWS::Serverless-2016-10-31 ... Resources: ApplicationResourceGroup: Type: AWS::ResourceGroups::Group Properties: Name: Fn::Join: - '' - - ApplicationInsights-SAM- - Ref: AWS::StackName ResourceQuery: Type: CLOUDFORMATION_STACK_1_0 ApplicationInsightsMonitoring: Type: AWS::ApplicationInsights::Application Properties: ResourceGroupName: Fn::Join: - '' - - ApplicationInsights-SAM- - Ref: AWS::StackName AutoConfigurationEnabled: 'true' DependsOn: ApplicationResourceGroup ``` + `AWS::ResourceGroups::Group` – Creates a group to organize your AWS resources in order to manage and automate tasks on a large number of resources at one time. Here, you create a resource group to use with CloudWatch Application Insights. For more information on this resource type, see [https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-resourcegroups-group.html](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-resourcegroups-group.html) in the *AWS CloudFormation User Guide*. + `AWS::ApplicationInsights::Application` – Configures CloudWatch Application Insights for the resource group. For more information on this resource type, see [https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-applicationinsights-application.html](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-applicationinsights-application.html) in the *AWS CloudFormation User Guide*. Both resources are automatically passed through to CloudFormation at application deployment. You can use the CloudFormation syntax in your AWS SAM template to configure CloudWatch Application Insights further. For more information, see [Use CloudFormation templates](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/appinsights-cloudformation.html) in the *Amazon CloudWatch User Guide*. When using the **sam init --application-insights** command, both of these resources are automatically generated in your AWS SAM template. Here is an example of a generated template. ``` AWSTemplateFormatVersion: '2010-09-09' Transform: AWS::Serverless-2016-10-31 Description: > sam-app-test Sample SAM Template for sam-app-test # More info about Globals: https://github.com/awslabs/serverless-application-model/blob/master/docs/globals.rst Globals: Function: Timeout: 3 MemorySize: 128 Resources: HelloWorldFunction: Type: AWS::Serverless::Function # More info about Function Resource: https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#awsserverlessfunction Properties: CodeUri: hello_world/ Handler: app.lambda_handler Runtime: python3.9 Architectures: - x86_64 Events: HelloWorld: Type: Api # More info about API Event Source: https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#api Properties: Path: /hello Method: get ApplicationResourceGroup: Type: AWS::ResourceGroups::Group Properties: Name: Fn::Join: - '' - - ApplicationInsights-SAM- - Ref: AWS::StackName ResourceQuery: Type: CLOUDFORMATION_STACK_1_0 ApplicationInsightsMonitoring: Type: AWS::ApplicationInsights::Application Properties: ResourceGroupName: Fn::Join: - '' - - ApplicationInsights-SAM- - Ref: AWS::StackName AutoConfigurationEnabled: 'true' DependsOn: ApplicationResourceGroup Outputs: # ServerlessRestApi is an implicit API created out of Events key under Serverless::Function # Find out more about other implicit resources you can reference within SAM # https://github.com/awslabs/serverless-application-model/blob/master/docs/internals/generated_resources.rst#api HelloWorldApi: Description: API Gateway endpoint URL for Prod stage for Hello World function Value: !Sub "https://${ServerlessRestApi}.execute-api.${AWS::Region}.amazonaws.com/Prod/hello/" HelloWorldFunction: Description: Hello World Lambda Function ARN Value: !GetAtt HelloWorldFunction.Arn HelloWorldFunctionIamRole: Description: Implicit IAM Role created for Hello World function Value: !GetAtt HelloWorldFunctionRole.Arn ``` ## Next steps After configuring CloudWatch Application Insights, use **sam build** to build your application and **sam deploy** to deploy your application. All CloudWatch Application Insights supported resources will be configured for monitoring. + For a list of supported resources, see [Supported logs and metrics](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/appinsights-logs-and-metrics.html) in the *Amazon CloudWatch User Guide*. + To learn how to access CloudWatch Application Insights, see [Access CloudWatch Application Insights](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/appinsights-accessing.html) in the *Amazon CloudWatch User Guide*. # Working with logs in AWS SAM Working with logs To simplify troubleshooting, the AWS SAM CLI has a command called `sam logs`. This command lets you fetch logs generated by your Lambda function from the command line. **Note** The `sam logs` command works for all AWS Lambda functions, not just the ones you deploy using AWS SAM. ## Fetching logs by CloudFormation stack When your function is a part of an CloudFormation stack, you can fetch logs by using the function's logical ID: ``` sam logs -n HelloWorldFunction --stack-name mystack ``` ## Fetching logs by Lambda function name Or, you can fetch logs by using the function's name: ``` sam logs -n mystack-HelloWorldFunction-1FJ8PD ``` ## Tailing logs Add the `--tail` option to wait for new logs and see them as they arrive. This is helpful during deployment or when you're troubleshooting a production issue. ``` sam logs -n HelloWorldFunction --stack-name mystack --tail ``` ## Viewing logs for a specific time range You can view logs for a specific time range by using the `-s` and `-e` options: ``` sam logs -n HelloWorldFunction --stack-name mystack -s '10min ago' -e '2min ago' ``` ## Filtering logs Use the `--filter` option to quickly find logs that match terms, phrases, or values in your log events: ``` sam logs -n HelloWorldFunction --stack-name mystack --filter "error" ``` In the output, the AWS SAM CLI underlines all occurrences of the word "error" so you can easily locate the filter keyword within the log output. ## Error highlighting When your Lambda function crashes or times out, the AWS SAM CLI highlights the timeout message in red. This helps you easily locate specific executions that are timing out within a giant stream of log output. ## JSON pretty printing If your log messages print JSON strings, the AWS SAM CLI automatically pretty prints the JSON to help you visually parse and understand the JSON.