fix(cli): fail fast on unknown config flags

acceptance/handle_config_file_test.go

@@ -102,7 +102,7 @@ username123: username
 			Expect(err).ToNot(HaveOccurred())
 
 			Eventually(session, "5s").Should(gexec.Exit(1))
-			Expect(session.Err.Contents()).To(ContainSubstring("unknown flag `username123'"))
+			Expect(session.Err.Contents()).To(ContainSubstring("unknown flag(s) [\"--username123\"]"))
 		})
 	})
 

cmd/loadConfigFile_test.go

@@ -1,8 +1,6 @@
 package cmd
 
 import (
-	"testing"
-
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
 )
@@ -22,8 +20,3 @@ var _ = Describe("parseOptions", func() {
 
 	})
 })
-
-func TestCmds(t *testing.T) {
-	RegisterFailHandler(Fail)
-	RunSpecs(t, "Cmds")
-}

cmd/main.go

@@ -659,11 +659,14 @@ func Main(sout io.Writer, serr io.Writer, version string, applySleepDurationStri
 		return err
 	}
 
-	parser.Options |= flags.HelpFlag
-
-	_, err = parser.ParseArgs(args)
-
+	// Strict flag validation block
+	err = validateCommandFlags(parser, args)
 	if err != nil {
+		return err
+	}
+
+	parser.Options |= flags.HelpFlag
+	if _, err = parser.ParseArgs(args); err != nil {
 		if e, ok := err.(*flags.Error); ok {
 			switch e.Type {
 			case flags.ErrHelp, flags.ErrCommandRequired:
@@ -787,3 +790,121 @@ func checkForVars(opts *options) error {
 
 	return nil
 }
+
+// validateCommandFlags checks if the provided command flags are valid for the given command.
+func validateCommandFlags(parser *flags.Parser, args []string) error {
+	// If no args, return nil
+	if len(args) == 0 {
+		return nil
+	}
+
+	// Find the command to validate flags for
+	cmdName := args[0]
+	var selectedCmd *flags.Command
+	for _, cmd := range parser.Commands() {
+		if cmd.Name == cmdName || contains(cmd.Aliases, cmdName) {
+			selectedCmd = cmd
+			break
+		}
+	}
+	// Unknown command, let parser handle it
+	if selectedCmd == nil {
+		return nil
+	}
+
+	// Find unknown flags
+	invalidFlags := findUnknownFlags(selectedCmd, args)
+
+	// If there are unknown flags, print an error and return
+	if len(invalidFlags) > 0 {
+		fmt.Fprintf(os.Stderr, "Error: unknown flag(s) %q for command '%s'\n", invalidFlags, selectedCmd.Name)
+		fmt.Fprintf(os.Stderr, "See 'om %s --help' for available options.\n", selectedCmd.Name)
+		return fmt.Errorf("unknown flag(s) %q for command '%s'", invalidFlags, selectedCmd.Name)
+	}
+	return nil
+}
+
+// findUnknownFlags checks for unknown flags in the provided args for the given command.
+func findUnknownFlags(selectedCmd *flags.Command, args []string) []string {
+	validFlags := make(map[string]bool)
+	addFlag := func(name string, takesValue bool) {
+		validFlags[name] = takesValue
+	}
+	for _, opt := range selectedCmd.Options() {
+		val := opt.Value()
+		_, isBool := val.(*bool)
+		_, isBoolSlice := val.(*[]bool)
+		takesValue := !(isBool || isBoolSlice)
+		if ln := opt.LongNameWithNamespace(); ln != "" {
+			addFlag("--"+ln, takesValue)
+		}
+		if opt.ShortName != 0 {
+			addFlag("-"+string(opt.ShortName), takesValue)
+		}
+	}
+	addFlag("--help", false)
+	addFlag("-h", false)
+
+	var invalidFlags []string
+	i := 1
+	for i < len(args) {
+		arg := args[i]
+		if !strings.HasPrefix(arg, "-") {
+			// Not a flag, just a value
+			// Example: args = ["upload-product", "file.pivotal"]
+			// "file.pivotal" is a positional argument or a value for a previous flag
+			i++
+			continue
+		}
+
+		// Split flag and value if --flag=value
+		flagName, hasEquals := arg, false
+		if eqIdx := strings.Index(arg, "="); eqIdx != -1 {
+			flagName = arg[:eqIdx]
+			hasEquals = true
+			// Example: arg = "--product=foo.pivotal" -> flagName = "--product", value = "foo.pivotal"
+		}
+
+		takesValue, isValid := validFlags[flagName]
+		if !isValid {
+			// Unknown flag
+			// Example: arg = "--notaflag" (not defined in command options)
+			invalidFlags = append(invalidFlags, flagName)
+			i++
+			continue
+		}
+
+		if takesValue {
+			if hasEquals {
+				// --flag=value, value is in this arg
+				// Example: arg = "--product=foo.pivotal"
+				i++
+			} else if i+1 < len(args) {
+				// --flag value, value is next arg (even if it looks like a flag)
+				// Example: args = ["--product", "--notaflag"]
+				// "--notaflag" is treated as the value for --product, not as a flag
+				i += 2
+			} else {
+				// --flag with missing value.
+				// No need to handle this here as this will handled appropriately by the parser.
+				// Example: args = ["--product"] (no value provided)
+				i++
+			}
+		} else {
+			// Boolean flag, no value expected
+			// Example: arg = "--help"
+			i++
+		}
+	}
+	return invalidFlags
+}
+
+// contains checks if a string is present in a list of strings.
+func contains(list []string, s string) bool {
+	for _, v := range list {
+		if v == s {
+			return true
+		}
+	}
+	return false
+}

cmd/suite_test.go

@@ -0,0 +1,13 @@
+package cmd
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestCmd(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Cmd Suite")
+}

cmd/validate_command_flags_test.go

@@ -0,0 +1,50 @@
+package cmd
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"github.com/jessevdk/go-flags"
+)
+
+var _ = Describe("validateCommandFlags", func() {
+	type uploadProductOptions struct {
+		Product         string   `long:"product" short:"p" description:"path to product" required:"true"`
+		PollingInterval int      `long:"polling-interval" short:"i" description:"interval (in seconds) at which to print status" default:"1"`
+		Shasum          string   `long:"shasum" description:"shasum of the provided product file to be used for validation"`
+		Version         string   `long:"product-version" description:"version of the provided product file to be used for validation"`
+		Config          string   `long:"config" short:"c" description:"path to yml file for configuration"`
+		VarsEnv         string   `long:"vars-env" description:"load variables from environment variables matching the provided prefix"`
+		VarsFile        []string `long:"vars-file" short:"l" description:"load variables from a YAML file"`
+		Var             []string `long:"var" short:"v" description:"load variable from the command line. Format: VAR=VAL"`
+	}
+
+	var parser *flags.Parser
+
+	BeforeEach(func() {
+		parser = flags.NewParser(nil, flags.Default)
+		parser.AddCommand("upload-product", "desc", "long desc", &uploadProductOptions{})
+	})
+
+	DescribeTable("flag validation",
+		func(args []string, wantErr bool, errMsg string) {
+			err := validateCommandFlags(parser, args)
+			if wantErr {
+				Expect(err).To(HaveOccurred())
+				Expect(err.Error()).To(ContainSubstring(errMsg))
+			} else {
+				Expect(err).ToNot(HaveOccurred())
+			}
+		},
+		Entry("no args", []string{}, false, ""),
+		Entry("valid flags", []string{"upload-product", "--product", "file.pivotal", "--polling-interval", "5", "--shasum", "abc123", "--product-version", "2.3.4"}, false, ""),
+		Entry("valid short flags", []string{"upload-product", "-p", "file.pivotal", "-i", "5"}, false, ""),
+		Entry("all config interpolation flags", []string{"upload-product", "-c", "config.yml", "--vars-env", "MY", "-l", "vars1.yml", "-l", "vars2.yml", "-v", "FOO=bar", "-v", "BAZ=qux", "-p", "file.pivotal"}, false, ""),
+		Entry("mix config and main flags", []string{"upload-product", "-p", "file.pivotal", "-c", "config.yml", "--vars-env", "MY", "--shasum", "abc123", "-l", "vars.yml", "-v", "FOO=bar"}, false, ""),
+		Entry("unknown flag with config flags", []string{"upload-product", "-p", "file.pivotal", "-c", "config.yml", "--notaflag"}, true, "unknown flag(s)"),
+		Entry("unknown flag", []string{"upload-product", "--notaflag"}, true, "unknown flag(s)"),
+		Entry("multiple unknown flags", []string{"upload-product", "--foo", "--bar"}, true, "unknown flag(s)"),
+		Entry("flag value looks like flag", []string{"upload-product", "--product", "--notaflag"}, false, ""),
+		Entry("unknown short flags", []string{"upload-product", "-p", "file.pivotal", "-x", "18000", "-z", "18000"}, true, "unknown flag(s)"),
+	)
+})

go.mod

@@ -97,8 +97,8 @@ require (
 	github.com/golang-jwt/jwt/v4 v4.5.1 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/snappy v0.0.4 // indirect
-	github.com/google/go-cmp v0.6.0 // indirect
-	github.com/google/pprof v0.0.0-20241101162523-b92577c0c142 // indirect
+	github.com/google/go-cmp v0.7.0 // indirect
+	github.com/google/pprof v0.0.0-20250403155104-27863c87afa6 // indirect
 	github.com/google/s2a-go v0.1.8 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/googleapis/enterprise-certificate-proxy v0.3.4 // indirect
@@ -143,21 +143,21 @@ require (
 	go.opentelemetry.io/otel/sdk v1.32.0 // indirect
 	go.opentelemetry.io/otel/sdk/metric v1.32.0 // indirect
 	go.opentelemetry.io/otel/trace v1.32.0 // indirect
-	golang.org/x/crypto v0.29.0 // indirect
-	golang.org/x/mod v0.22.0 // indirect
-	golang.org/x/net v0.31.0 // indirect
-	golang.org/x/sync v0.9.0 // indirect
-	golang.org/x/sys v0.27.0 // indirect
-	golang.org/x/term v0.26.0 // indirect
-	golang.org/x/text v0.20.0 // indirect
+	golang.org/x/crypto v0.36.0 // indirect
+	golang.org/x/mod v0.24.0 // indirect
+	golang.org/x/net v0.37.0 // indirect
+	golang.org/x/sync v0.12.0 // indirect
+	golang.org/x/sys v0.32.0 // indirect
+	golang.org/x/term v0.30.0 // indirect
+	golang.org/x/text v0.23.0 // indirect
 	golang.org/x/time v0.8.0 // indirect
-	golang.org/x/tools v0.27.0 // indirect
+	golang.org/x/tools v0.31.0 // indirect
 	google.golang.org/genproto v0.0.0-20241104194629-dd2ea8efbc28 // indirect
 	google.golang.org/genproto/googleapis/api v0.0.0-20241104194629-dd2ea8efbc28 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20241104194629-dd2ea8efbc28 // indirect
 	google.golang.org/grpc v1.68.0 // indirect
 	google.golang.org/grpc/stats/opentelemetry v0.0.0-20241028142157-ada6787961b3 // indirect
-	google.golang.org/protobuf v1.35.1 // indirect
+	google.golang.org/protobuf v1.36.5 // indirect
 	gopkg.in/cheggaaa/pb.v1 v1.0.28 // indirect
 	gopkg.in/go-playground/assert.v1 v1.2.1 // indirect
 )