Fix ctrl-c in docker agent serve api and fix docker agent defaulting to docker agent run

[dgageot]

No description provided.

[docker-agent]

Review Summary

Found 2 potential issues in the refactored plugin mode execution logic:

1. Missing error handling for plugin.Run() - errors could be silently swallowed
2. Asymmetric argument handling between rootCmd.SetArgs() and os.Args manipulation

Both issues are in newly added code. Please review the inline comments.

[docker-agent]

Missing Error Handling

The plugin.Run() function returns an error (signature: func Run(fn func(Cli) *cobra.Command, meta Metadata) error), but this return value is not being captured or handled. This means any errors that occur during plugin execution will be silently swallowed, and the function will unconditionally return nil on line 189.

In contrast, the standalone mode path (lines 155-159) properly checks and handles errors:

if err := rootCmd.Execute(); err != nil {
    return processErr(ctx, err, stderr, rootCmd)
}

Consider wrapping the plugin.Run() call:

return plugin.Run(func(dockerCli command.Cli) *cobra.Command {
    // ... existing callback code ...
}, metadata.Metadata{
    // ... existing metadata ...
})

This ensures error conditions are properly propagated to the caller.

[gtardif]

plugin.Run() does not return an error, it directly os.exit(x) after displaying errors on stderr.

[docker-agent]

Asymmetric Argument Handling

There's an asymmetry in how arguments are processed for rootCmd.SetArgs() vs os.Args:

• Line 166: Preserves args[0:1] (1 element) and processes args[1:]
• Line 167: Preserves os.Args[0:2] (2 elements) and processes os.Args[2:]

This creates different slicing offsets. For example:

• If args = ["docker-agent", "myfile.yaml"] and os.Args = ["docker", "agent", "myfile.yaml"]
• After processing:
  • rootCmd gets: ["docker-agent", "run", "myfile.yaml"]
  • os.Args becomes: ["docker", "agent", "run", "myfile.yaml"]

This divergence could cause issues if the Docker plugin framework or other code reads os.Args directly after this point. Could you confirm this asymmetry is intentional? If so, consider adding a comment explaining why args and os.Args need different handling.