Support for using unix pipes in devcontainer runArgs, in particular for --env-file

[jamesthurley]

Docker already supports using unix pipes to specify an environment variable file as follows:

docker run --env-file <(echo 'TEST_VARIABLE=TEST_VALUE') --rm ubuntu env

In my devcontainer.json I've tried doing the following:

  "runArgs": [
    "--env-file",
    "<(echo 'TEST_VARIABLE=TEST_VALUE')"
  ],

But I get the following error when the devcontainer starts:

docker: open <(echo 'TEST_VARIABLE=TEST_VALUE'): no such file or directory.

Specifically, I want to do this:

  "runArgs": [
    "--env-file",
    "<(op inject -i .env)"
  ],

This allows my devcontainer environment variables to be stored in 1Password and injected by the 1Password CLI.

My current workaround is the far less satisfactory:

  // Use the 1Password CLI to generate a .env.tmp file with secrets.
  "initializeCommand": "op inject --force --in-file .env --out-file .env.tmp",
 
  // Load the env file generated by the 1Password CLI.
  "runArgs": [
    "--env-file",
    ".env.tmp"
  ],

  // Clean up env file generated by the 1Password CLI.
  "postStartCommand": "rm .env.tmp",

Having to store secrets temporarily on disk is not great, and the postStartCommand isn't always run as I expected, leaving the secrets file sitting on disk after the devcontainer starts. Support for using unix pipes in runArgs would eliminate the need for the temp file and simplify the configuration.

[chrmarti]

I think this is a shell feature and we run docker without shell.

[vs-code-engineering]

This feature request is now a candidate for our backlog. The community has 60 days to upvote the issue. If it receives 10 upvotes we will move it to our backlog. If not, we will close it. To learn more about how we handle feature requests, please see our documentation.

Happy Coding!

[vs-code-engineering]

This feature request has not yet received the 10 community upvotes it takes to make to our backlog. 10 days to go. To learn more about how we handle feature requests, please see our documentation.

Happy Coding

[vs-code-engineering]

🙁 In the last 60 days, this feature request has received less than 10 community upvotes and we closed it. Still a big Thank You to you for taking the time to create this issue! To learn more about how we handle feature requests, please see our documentation.

Happy Coding!