az acr build fails because of access to file he does not need

Question

I'm building manually docker images from .NET 6 projects on Windows and uploading them to a docker container registry in Azure.

I'm in the folder with the dockerfile and run:

az acr build --registry MyContainerRegistry --image project/imagename:v1 . 

And receive the following error message:

Packing source code into tar to upload...
[WinError 3] The system cannot find the path specified: '.\\some_directory_hierarchy\\obj\\Debug\\netcoreapp3.1\\OneOfMyProjects.GeneratedMSBuildEditorConfig.editorconfig'

The dockerfile has no reference to this file, and AFAIK editorconfig isn't needed in the build process. From the first line, I can tell that no step defined in the docker file is run.

Just to highlight:

• I am logged in to Azure
• The same way I'm doing it worked with multiple docker images in the same project when uploading to the same registry.
• When using docker build on the same dockerfile the process runs and finishes successfully.

Why az acr build does not work?

Answer 1

It appears that the build process is attempting to include a file (OneOfMyProjects.GeneratedMSBuildEditorConfig.editorconfig) in the source code tarball that might not be necessary for the Docker build.

• You can use a .dockerignore file to exclude unnecessary files or directories. Create a file named .dockerignore in the same directory as your Dockerfile and list files or patterns to exclude

Here, I have a image in my ACR pushed from my Docker desktop. After the above changes, I can run the az acr build as expected.

• Run the command - az acr build --registry testregdec7 --image my-sample-app .