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Azure Pipelines - A template expression is not allowed in this context

In my attempt to further optimize our deployment process, I tried to move most of the pipeline logic to a YAML template. This is how the template looked like(I simplified it a little bit):

However when I tried to create a pipeline using this template I got the following error message:

/cd-template.yml (Line: 14, Col: 14): A template expression is not allowed in this context

The problem is that I’m trying to use a template expression inside a pipeline resource.

First I was thinking I did something wrong but then I found the following announcement in the release notes:

Previously, compile-time expressions (${{ }}) were not allowed in the resources section of an Azure Pipelines YAML file. With this release, we have lifted this restriction for containers. This allows you to use runtime parameter contents inside your resources, for example to pick a container at queue time. We plan to extend this support to other resources over time.

As stated above, compile time expressions are not allowed in the resources section. With the change above it becomes possible but only when using the container resource.

So no luck for me! Hopefully this will change in future versions…

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