Method InstrumentCobraCommands

cli/command/telemetry_utils.go:29–65

InstrumentCobraCommands wraps all cobra commands' RunE funcs to set a command duration metric using otel. Note: this should be the last func to wrap/modify the PersistentRunE/RunE funcs before command execution. can also be used for spans!

(ctx context.Context, cmd *cobra.Command)

//
// can also be used for spans!
func (cli *DockerCli) InstrumentCobraCommands(ctx context.Context, cmd *cobra.Command) {
	// If PersistentPreRunE is nil, make it execute PersistentPreRun and return nil by default
	ogPersistentPreRunE := cmd.PersistentPreRunE
	if ogPersistentPreRunE == nil {
		ogPersistentPreRun := cmd.PersistentPreRun
		//nolint:unparam // necessary because error will always be nil here
		ogPersistentPreRunE = func(cmd *cobra.Command, args []string) error {
			ogPersistentPreRun(cmd, args)
			return nil
		}
		cmd.PersistentPreRun = nil
	}

	// wrap RunE in PersistentPreRunE so that this operation gets executed on all children commands
	cmd.PersistentPreRunE = func(cmd *cobra.Command, args []string) error {
		// If RunE is nil, make it execute Run and return nil by default
		ogRunE := cmd.RunE
		if ogRunE == nil {
			ogRun := cmd.Run
			//nolint:unparam // necessary because error will always be nil here
			ogRunE = func(cmd *cobra.Command, args []string) error {
				ogRun(cmd, args)
				return nil
			}
			cmd.Run = nil
		}
		cmd.RunE = func(cmd *cobra.Command, args []string) error {
			// start the timer as the first step of every cobra command
			stopInstrumentation := cli.StartInstrumentation(cmd)
			cmdErr := ogRunE(cmd, args)
			stopInstrumentation(cmdErr)
			return cmdErr
		}

		return ogPersistentPreRunE(cmd, args)
	}
}

// StartInstrumentation instruments CLI commands with the individual metrics and spans configured.
// It's the main command OTel utility, and new command-related metrics should be added to it.