avoid failing compose config on failure to load stack

[jordanstephens]

Description

This PR solves a regression where we are exiting early with an error after failing to load a stack during defang compose config. In this case, we want to only warn about the error, then continue.

Linked Issues

Checklist

• I have performed a self-review of my code
• I have added appropriate tests
• I have updated the Defang CLI docs and/or README to reflect my changes, if necessary

Summary by CodeRabbit

• Bug Fixes
  • The compose command now handles session load failures more gracefully: it logs a warning and continues execution instead of aborting, allowing subsequent operations (like account info retrieval) to run when possible.

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[coderabbitai]

📝 Walkthrough

Walkthrough

makeComposeConfigCmd in compose.go now logs a warning when session/stack loading fails instead of returning the error, allowing command execution to continue after a failed session initialization.

Changes

Cohort / File(s)	Summary
Error handling change src/cmd/cli/command/compose.go	Replaced returning the session-load error with a warning log (non-fatal), so execution proceeds even if session creation/stack loading fails.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• Stacks Cleanup #1855: Rewires session/stack usage in the same file; related to how stack/session state is obtained and used.
• avoid ignoring missing stack error #1835: Adjusts handling of missing-stack errors in the same code path; directly related to error propagation versus suppression.
• ensure stack env vars are loaded #1790: Changes control flow around session/stack loading during CLI command execution, touching similar logic.

Suggested reviewers

• lionello

Poem

🐇 A soft thump and gentle hop,
Stack failed to load, but we don't stop.
A warning hums, the command goes on,
Moonlit paths keep bouncing on. 🌙

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title directly and clearly describes the main change: preventing 'compose config' from failing when stack loading fails, which aligns with the changeset's modification to log a warning and continue instead of returning an error.

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✨ Finishing touches

• 📝 Generate docstrings

Warning

There were issues while running some tools. Please review the errors and either fix the tool's configuration or disable the tool if it's a critical failure.

🔧 golangci-lint (2.5.0)

level=warning msg="[linters_context] running gomodguard failed: unable to read module file go.mod: current working directory must have a go.mod file: if you are not using go modules it is suggested to disable this linter"
level=error msg="[linters_context] typechecking error: pattern ./...: directory prefix . does not contain main module or its selected dependencies"

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[coderabbitai]

Actionable comments posted: 0

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

src/cmd/cli/command/compose.go (1)

546-558: Nil pointer dereference: session will be nil after error from newCommandSessionWithOpts.

The function returns nil when LoadSession fails. The code logs the error at line 550 but continues execution, unconditionally accessing session.Provider (line 553), session.Loader (line 558), and session.Stack (line 582), causing a panic.

Either return after logging the error, check if session is nil before using it, or ensure newCommandSessionWithOpts always returns a usable partial session.