Fix client command detection when flags precede subcommand

[antcybersec]

Summary

• Resolve the active subcommand with cobra's Find instead of assuming args[1] is always the command name
• Fixes incorrect enrollment validation when global flags (e.g. --loglevel warning) appear before enroll, gencsr, getcacert, or getcainfo
• Add unit tests for command resolution and the reported enroll failure mode

Problem

fabric-ca-client --loglevel warning enroll -u ... was treated as if the subcommand was warning, so ConfigInit incorrectly required prior enrollment and failed with:

Enrollment information does not exist. Please execute enroll command first.

Test plan

• go test ./cmd/fabric-ca-client/command/ -run 'TestResolveCommandName|TestEnrollWithGlobalFlagsBeforeSubcommand'
• go test ./cmd/fabric-ca-client/command/

Fixes #465

[bestbeforetoday]

Thank you very much for this contribution. Just a concern with one of the unit tests (see inline comments); otherwise looks good to me.

[bestbeforetoday]

I think this configuration should be guaranteed to fail so it should require an error, not just assert if an error occurs. The NotContians assertion on the error message also seems error-prone since the error messages could be changed in the future, which would make this test pass regardless of actual behaviour.

I think this really needs to change to a positive test:

Suggested change

	defYaml := util.GetDefaultConfigFile("fabric-ca-client")
	os.Remove(defYaml)
	defer os.Remove(defYaml)
	err := RunMain([]string{cmdName, "--loglevel", "warning", "enroll", "-d"})
	if assert.Error(t, err) {
	assert.NotContains(t, err.Error(), "Enrollment information does not exist",
	"enroll with flags before subcommand should not require prior enrollment")
	}
	adminHome := filepath.Join(tdDir, "enrolladminhome")
	// Remove admin home directory if it exists
	err := os.RemoveAll(adminHome)
	require.NoErrorf(t, err, "Failed to remove directory %s: %s", adminHome, err)
	// Remove admin home directory that this test is going to create before
	// exiting the test case
	defer os.RemoveAll(adminHome)
	srv := setupEnrollTest(t)
	// Cleanup before exiting the test case
	defer stopAndCleanupServer(t, srv)
	err = RunMain([]string{cmdName, "--loglevel", "warning", "enroll", "-d", "-u", enrollURL, "-H", adminHome})
	require.NoError(t, err, "enroll should succeed with global flags before subcommand")

[antcybersec]

Good point — updated to a positive test that enrolls against a running CA server with global flags before the subcommand. Thanks for the suggestion.