Azure containerapp compose create does not read unset environment variable defaults

[jackroc97]

Describe the bug

Bug Description

I am building a containerapp using az containerapp compose create. My compose file's environment section declares several variables that are to be read in from environment variables, many of which have default values. Rather than using the default value for unset environment variables, the command uses the literal string of the variable reference as the value.

Example

Say this is the compose file:

environment:
  VAR_A: ${VAR_A}
  VAR_B: ${VAR_B:-foo}
  VAR_C: ${VAR_C:-bar}

And my locally set environment variables are:

VAR_A=hello
VAR_B=world
# VAR_C intentionally left un-set

Azure will read my environment variables as:

"env": [
  {
     "name": "VAR_A",
     "value": "hello"
  },
  {
     "name": "VAR_B",
     "value": "world"
  },
  {
     "name": "VAR_C",
     "value": "${VAR_C:-bar}" // BUG: This should be "bar" since VAR_C was not set
  },
]

Related command

az containerapp compose create

Errors

Please see description

Issue script & Debug output

Please see description.

Expected behavior

Default values for un-declared env variables referenced in the compose file should be interpreted correctly.

Environment Summary

azure-cli 2.81.0
containerapp extension 1.3.0b1

Additional context

No response

[yonzhan]

Thank you for opening this issue, we will look into it.

[microsoft-github-policy-service]

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @howang-ms, @Greedygre.