Trigger a release in an external Azure DevOps On-Prem or Azure DevOps

A picture


Hans Oude Middendorp



Reading time

3 minutes

I recently stumbled on a problem that required the ability to trigger a release outside the project and even outside our on-premises Azure DevOps. To tackle this, I created a custom build/release task that enables creating a release in another Azure DevOps On-Prem project, project collection, farm or in Azure DevOps.


The solution is based on the REST API that comes with Azure DevOps On-Prem or is available in Azure DevOps. This API is described here. We will use two methods:

  • get release definitions
  • create a release

We use a personal access token to authenticate the calls to the API. I explain how to create a personal access token in my blog post: Custom Azure DevOps pipeline task to execute a SQL script.

Encode the personal access token:

  $base64AuthInfo = [Convert]::ToBase64String([Text.Encoding]::ASCII.GetBytes(("{0}:{1}" -f "", $personalAccessToken)))

The URI definition for Azure DevOps:

  $uri = "https://$($vstsAccount)$($projectName)/_apis/release/definitions?api-version=3.0-preview.2"

And for Azure DevOps On-Prem:

  $uri = "$($TFSUri)/$($projectName)/_apis/release/definitions?api-version=3.0-preview.2"

Invoke the REST call and capture result:
$result = Invoke-RestMethod -Uri $uri -Method Get -ContentType "application/json" -Headers @{Authorization=("Basic {0}" -f $base64AuthInfo)}

From the list of definitions, we will select the right one by filtering by name, which we ask for in the task setup. We store the ID in the variable $releaseID.

Once a release definition has been selected, we create a new release by using the second method, giving a body with no artifact description:

  $body = '{
  "definitionId": ' + $releaseID + ',
  "description": "' + $releaseDescription + '"

The variable $releaseDescription comes from the task setup page.

To start the release we call another REST method. For Azure DevOps:

  $uri = "https://$($vstsAccount)$($projectName)/_apis/release/releases?api-version=3.0-preview.2"

And for Azure DevOps On-Prem:

  $uri = "$($TFSUri)/$($projectName)/_apis/release/releases?api-version=3.0-preview.2"

The method is invoked like this:

  $releaseresponse = Invoke-RestMethod -Method Post -ContentType application/json -Uri $uri -Headers @{Authorization=("Basic {0}" -f $base64authinfo)} -Body $body

Using the custom task

The task can be used in a build or release definition.

If you select Azure DevOps, you will need to enter a Azure DevOps Account Name, i.e. the part between “https://” and “".

If Azure DevOps On-Prem is used, you will need to enter the full URI to the Azure DevOps On-Prem instance, including protocol, port and project collection name. For example:


The Release Description field is used to enter a comment on the release.

You can find the complete sources of this solution on GitHub. To find out how to install this solution in your own environment, you can read my blog post Custom Azure DevOps pipeline task to execute a SQL script.

Blijf op de hoogte met Craft

Wil jij geen events meer missen en via blogs op de hoogte blijven van alle ontwikkelingen rondom .NET Development? Meld je dan aan voor de Craft-update!