docker-compose failing to read env_file with UTF8 BOM

[vtortola]

Hi!

I was trying to use the env_file feature in docker-compose but the environment variables were not being readed from the file.

In this example project you will see two files named config.env and config2.env. They almost contains the same data, but config.env starts with the UTF8 BOM, causing docker-compose to not read the variables.

Most text editors shows the same content for both files.

During the execution, the log shows that something is going wrong with the parsing:

config.env:

    environment:
      NUGET_FALLBACK_PACKAGES: /root/.nuget/fallbackpackages
      "\uFEFFTEST": Compose

config2.env

    environment:
      NUGET_FALLBACK_PACKAGES: /root/.nuget/fallbackpackages
      TEST: Compose

Would it be possible for docker in general to be aware of the UTF8 BOM in configuration files?

How did happen?

Well it seems that when you add a text file in Visual Studio, it adds the UTF8 BOM by default. I generated the second file that has to BOM using the Windows Explorer contextual menu "New File".

Maybe: StackOverflow: Reading Unicode file data with BOM chars in Python

[shin-]

Thank you for the report!