fix: add extra request to template cmd to avoid subsequent if repo does not exist (#1206) (#1249)

cmd/client.go

@@ -34,7 +34,7 @@ type ClientConfig struct {
 // for use by commands.
 // See the NewClient constructor which is the fully populated ClientFactory used
 // by commands by default.
-// See NewClientFactory which constructs a minimal CientFactory for use
+// See NewClientFactory which constructs a minimal ClientFactory for use
 // during testing.
 type ClientFactory func(ClientConfig, ...fn.Option) (*fn.Client, func())
 
@@ -52,7 +52,7 @@ func NewClientFactory(n func() *fn.Client) ClientFactory {
 // NewClient constructs an fn.Client with the majority of
 // the concrete implementations set.  Provide additional Options to this constructor
 // to override or augment as needed, or override the ClientFactory passed to
-// commands entirely to mock for testing. Note the reutrned cleanup function.
+// commands entirely to mock for testing. Note the returned cleanup function.
 // 'Namespace' is optional.  If not provided (see DefaultNamespace commentary),
 // the currently configured is used.
 // 'Verbose' indicates the system should write out a higher amount of logging.

cmd/templates.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"net/http"
 	"os"
 	"strings"
 	"text/tabwriter"
@@ -14,6 +15,9 @@ import (
 	fn "knative.dev/kn-plugin-func"
 )
 
+// ErrTemplateRepoDoesNotExist is a sentinel error if a template repository responds with 404 status code
+var ErrTemplateRepoDoesNotExist = errors.New("template repo does not exist")
+
 func NewTemplatesCmd(newClient ClientFactory) *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "templates",
@@ -60,7 +64,7 @@ EXAMPLES
 		PreRunE: bindEnv("json", "repository"),
 	}
 
-	cmd.Flags().BoolP("json", "", false, "Set output to JSON format. (Env: $FUNC_JSON)")
+	cmd.Flags().Bool("json", false, "Set output to JSON format. (Env: $FUNC_JSON)")
 	cmd.Flags().StringP("repository", "r", "", "URI to a specific repository to consider (Env: $FUNC_REPOSITORY)")
 
 	cmd.SetHelpFunc(defaultTemplatedHelp)
@@ -79,13 +83,25 @@ func runTemplates(cmd *cobra.Command, args []string, newClient ClientFactory) (e
 		return
 	}
 
+	// Simple ping to the repo to avoid subsequent errors from http package if it does not exist
+	if cfg.Repository != "" {
+		res, err := http.Get(cfg.Repository)
+		if err != nil {
+			return err
+		}
+		defer res.Body.Close()
+		if res.StatusCode == http.StatusNotFound {
+			return ErrTemplateRepoDoesNotExist
+		}
+	}
+
 	// Client which will provide data
 	client, done := newClient(ClientConfig{Verbose: cfg.Verbose},
 		fn.WithRepository(cfg.Repository),             // Use exactly this repo OR
 		fn.WithRepositoriesPath(cfg.RepositoriesPath)) // Path on disk to installed repos
 	defer done()
 
-	// For a singl language runtime
+	// For a single language runtime
 	// -------------------
 	if len(args) == 1 {
 		templates, err := client.Templates().List(args[0])
@@ -105,7 +121,7 @@ func runTemplates(cmd *cobra.Command, args []string, newClient ClientFactory) (e
 		}
 		return nil
 	} else if len(args) > 1 {
-		return errors.New("unexpected extra arguments.")
+		return errors.New("unexpected extra arguments")
 	}
 
 	// All language runtimes

cmd/templates_test.go

@@ -1,8 +1,11 @@
 package cmd
 
 import (
+	"errors"
 	"testing"
 
+	"gotest.tools/v3/assert"
+
 	fn "knative.dev/kn-plugin-func"
 	. "knative.dev/kn-plugin-func/testing"
 )
@@ -140,3 +143,24 @@ http`
 	}
 
 }
+
+func TestTemplates_ErrTemplateRepoDoesNotExist(t *testing.T) {
+	defer t.Setenv("XDG_CONFIG_HOME", t.TempDir())
+	cmd := NewTemplatesCmd(NewClientFactory(func() *fn.Client {
+		return fn.New()
+	}))
+	cmd.SetArgs([]string{"--repository", "https://github.com/boson-project/repo-does-not-exist"})
+	err := cmd.Execute()
+	assert.Assert(t, err != nil)
+	assert.Assert(t, errors.Is(err, ErrTemplateRepoDoesNotExist))
+}
+
+func TestTemplates_WrongRepositoryUrl(t *testing.T) {
+	defer t.Setenv("XDG_CONFIG_HOME", t.TempDir())
+	cmd := NewTemplatesCmd(NewClientFactory(func() *fn.Client {
+		return fn.New()
+	}))
+	cmd.SetArgs([]string{"--repository", "wrong://github.com/boson-project/repo-does-not-exist"})
+	err := cmd.Execute()
+	assert.Assert(t, err != nil)
+}