# Start a pipeline with a source revision override
<a name="pipelines-trigger-source-overrides"></a>

You can use overrides to start a pipeline with a specific source revision ID that you provide for the pipeline execution. For example, if you want to start a pipeline that will process a specific commit ID from your CodeCommit source, you can add the commit ID as an override when you start your pipeline.

**Note**  
You can also create a source override using input transform entry to use the `revisionValue` in EventBridge for your pipeline event, where the `revisionValue` is derived from the source event variable for your object key, commit, or image ID. For more information, see the optional step for input transform entry included in the procedures under [Amazon ECR source actions and EventBridge resources](create-cwe-ecr-source.md), [Connecting to Amazon S3 source actions with a source enabled for events](create-S3-source-events.md), or [CodeCommit source actions and EventBridge](triggering.md).

There are four types of source revision for `revisionType`: 
+ `COMMIT_ID`
+ `IMAGE_DIGEST`
+ `S3_OBJECT_VERSION_ID`
+ `S3_OBJECT_KEY`

**Note**  
For the `COMMIT_ID` and `IMAGE_DIGEST` types of source revisions, the source revision ID applies to all content in the repository, across all branches.

**Note**  
For the `S3_OBJECT_VERSION_ID` and `S3_OBJECT_KEY` types of source revisions, either of the types can be used independently, or they can be used together to override the source with a specific ObjectKey and VersionID. For `S3_OBJECT_KEY`, the configuration parameter `AllowOverrideForS3ObjectKey` needs to be set to `true`. For more information on S3 source configuration parameters, see [Configuration parameters](action-reference-S3.md#action-reference-S3-config).

**Topics**
+ [Start a pipeline with a source revision override (console)](#pipelines-trigger-source-overrides-console)
+ [Start a pipeline with a source revision override (CLI)](#pipelines-trigger-source-overrides-cli)

## Start a pipeline with a source revision override (console)
<a name="pipelines-trigger-source-overrides-console"></a>

**To manually start a pipeline and run the most recent revision through a pipeline**

1. Sign in to the AWS Management Console and open the CodePipeline console at [http://console.aws.amazon.com/codesuite/codepipeline/home](http://console.aws.amazon.com/codesuite/codepipeline/home).

1. In **Name**, choose the name of the pipeline you want to start. 

1. On the pipeline details page, choose **Release change**. Choosing **Release change** opens the **Release change** window. For **Source revision override**, choose the arrow to expand the field. In **Source**, enter the source revision ID. For example, if your pipeline has a CodeCommit source, choose the commit ID from the field that you want to use.  
![\[An example of the overrides screen in CodePipeline.\]](http://docs.aws.amazon.com/codepipeline/latest/userguide/images/overrides.png)

## Start a pipeline with a source revision override (CLI)
<a name="pipelines-trigger-source-overrides-cli"></a>

**To manually start a pipeline and run the specified source revision ID for an artifact through a pipeline**

1. Open a terminal (Linux, macOS, or Unix) or command prompt (Windows) and use the AWS CLI to run the **start-pipeline-execution** command, specifying the name of the pipeline you want to start. You also use the **--source-revisions** argument to provide the source revision ID. The source revision is made up of the actionName, revisionType, and revisionValue. Valid revisionType values are `COMMIT_ID | IMAGE_DIGEST | S3_OBJECT_VERSION_ID | S3_OBJECT_KEY`. 

   In the following example, to start running the specified change through a pipeline named **codecommit-pipeline**, the following command species a source action name of Source, a revision type of `COMMIT_ID`, and a commit ID of `78a25c18755ccac3f2a9eec099dEXAMPLE`.

   ```
   aws codepipeline start-pipeline-execution --name codecommit-pipeline --source-revisions actionName=Source,revisionType=COMMIT_ID,revisionValue=78a25c18755ccac3f2a9eec099dEXAMPLE --region us-west-1
   ```

1. To verify success, view the returned object. This command returns an execution ID, similar to the following:

   ```
   {
       "pipelineExecutionId": "c53dbd42-This-Is-An-Example"
   }
   ```
**Note**  
After you have started the pipeline, you can monitor its progress in the CodePipeline console or by running the **get-pipeline-state** command. For more information, see [View pipelines (console)](pipelines-view-console.md) and [View pipeline details and history (CLI)](pipelines-view-cli.md).