Creating and using configuration aliases with MediaTailor - AWS Elemental MediaTailor
Step 1: Create configuration aliasesStep 2: Use configuration aliases in session initialization

Creating and using configuration aliases with MediaTailor

Before you start to use domain variables, you create configuration aliases for your configuration. You use the configuration aliases as domain replacement variables at session initialization time.

Restrictions

Note the following restrictions when using configuration aliases:

  • All dynamic variables used in the domain must be defined as a ConfigurationAliases dynamic variable.

  • The player parameter variables must be prefixed with player_params.. For example, player_params.origin_domain.

  • The list of aliased values must be exhaustive for domain variables in critical URLs (VideoContentSourceUrl, AdSegmentUrlPrefix, ContentSegmentUrlPrefix).

  • If a request is made for a domain variable in critical URLs that either doesn't specify the dynamic variable or uses an invalid alias, the request will fail with an HTTP 400 status code. Non-critical fields (SlateAdUrl, TranscodeProfileName, bumper URLs) will log warnings but not fail the request.

Fallback behavior for missing aliases

When configuration aliases are not found or are invalid, MediaTailor implements the following fallback behavior:

  • Domain variables: If a domain variable alias is missing or invalid, the request fails with HTTP 400 status code. All domain variables must have valid aliases defined.

  • Non-domain variables: For variables used in non-domain portions of URLs (such as path elements or query parameters), missing aliases result in empty string replacement.

  • Configuration validation: MediaTailor validates that all required aliases are present during configuration creation and update operations.

Step 1: Create configuration aliases

To create configuration aliases to use for domain replacement using the MediaTailor console, perform the following procedure.

Console
To create configuration aliases using the console

  1. Open the MediaTailor console at https://console.aws.amazon.com/mediatailor/.

  2. On the Configuration aliases section on the Configurations page, choose Add player parameter.

  3. For Player parameter, enter the name of the player parameter that you want to use as a dynamic variable. For example, player_params.origin_domain.

  4. For Aliases, enter the aliases and their values that you want to use for the player parameter.

  5. Choose OK.

    AWS Elemental MediaTailor displays the new parameter in the table in the Configuration aliases section.

  6. Repeat the preceding steps to add more player parameters.

  7. Choose Save.

API
To create configuration aliases using the API

When you create or update a MediaTailor configuration, use the ConfigurationAliases parameter with the following JSON structure: 

{
                "ConfigurationAliases": {
                "player_params.origin_domain": {
                "pdx": "abc.mediapackage.us-west-2.amazonaws.com",
                "iad": "xyz.mediapackage.us-east-1.amazonaws.com"
                },
                "player_params.ad_type": {
                "customized": "abc12345",
                "default": "defaultAdType"
                }
                }
                }

Step 2: Use configuration aliases in session initialization

After you set up the configuration aliases, you can use them as replacement variables for domains in your session initialization request. This enables you to dynamically configure the domains for your session.

Example Basic configuration aliases example

Here's a basic example of a configuration that includes configuration aliases and dynamic domain variables:

PUT /playbackConfiguration
{
    "Name": "aliasedConfig",
    "AdDecisionServerUrl": "https://abc.execute-api.us-west-2.amazonaws.com/ads?sid=[session.id]&ad_type=[player_params.ad_type]",
    "VideoContentSourceUrl": "https://[player_params.origin_domain].mediapackage.[player_params.region].amazonaws.com/out/v1/[player_params.endpoint_id]",
    "ConfigurationAliases": {
        "player_params.origin_domain": {
            "pdx": "abc",
            "iad": "xyz"
        },
        "player_params.region": {
            "pdx": "us-west-2",
            "iad": "us-east-1"
        },
        "player_params.endpoint_id": {
            "pdx": "abcd",
            "iad": "wxyz"
        },
        "player_params.ad_type": {
            "customized": "abc12345",
            "default": "defaultAdType"
        }
    }
}
Example Session initialization with aliases

Using the preceding configuration, a session initialization request using the player variables and aliases would look similar to the following:

POST index.m3u8
{
    "playerParams": {
        "origin_domain": "pdx",
        "region": "pdx",
        "endpoint_id": "pdx",
        "ad_type": "customized"
    }
}

MediaTailor replaces the alias strings with the mapped values in the configuration aliases configuration.

The request to the ADS will look like the following:

https://abc.execute-api.us-west-2.amazonaws.com/ads?sid=[session.id]&ad_type=abc12345

The request to the origin for the manifests will look like the following:

https://abc.mediapackage.us-west-2.amazonaws.com/out/v1/abcd