Guard against user specifying an invalid type on generate

[#140148083] Wrong error presented when setting with an invalid type

commands/generate.go

@@ -1,6 +1,8 @@
 package commands
 
 import (
+	"errors"
+
 	"github.com/pivotal-cf/credhub-cli/actions"
 	"github.com/pivotal-cf/credhub-cli/client"
 	"github.com/pivotal-cf/credhub-cli/config"
@@ -37,9 +39,14 @@ type GenerateCommand struct {
 }
 
 func (cmd GenerateCommand) Execute([]string) error {
+	validTypes := []string{"value", "password", "ssh", "rsa", "certificate"}
+
 	if cmd.SecretType == "" {
 		cmd.SecretType = "password"
 	}
+	if !contains(validTypes, cmd.SecretType) {
+		return errors.New("The request does not include a valid type. Valid values include 'value', 'password', 'certificate', 'ssh' and 'rsa'.")
+	}
 
 	cfg := config.ReadConfig()
 	repository := repositories.NewSecretRepository(client.NewHttpClient(cfg))

commands/generate_test.go

@@ -374,6 +374,18 @@ var _ = Describe("Generate", func() {
 			}
 		})
 
+		It("displays an error when invalid type is specified", func() {
+			server.AppendHandlers(
+				RespondWith(http.StatusBadRequest, `{"error": "you fail."}`),
+			)
+
+			session := runCommand("generate", "-t", "potato", "-n", "my-value")
+
+			Eventually(session).Should(Exit(1))
+
+			Expect(session.Err).To(Say("The request does not include a valid type. Valid values include 'value', 'password', 'certificate', 'ssh' and 'rsa'."))
+		})
+
 		It("displays the server provided error when an error is received", func() {
 			server.AppendHandlers(
 				RespondWith(http.StatusBadRequest, `{"error": "you fail."}`),