Merge pull request #3877 from thaJeztah/minor_context_cleanups

context: various minor cleanups and fixes

cli/command/context.go

@@ -58,5 +58,8 @@ func GetDockerContext(storeMetadata store.Metadata) (DockerContext, error) {
 	if !ok {
 		return DockerContext{}, errors.New("context metadata is not a valid DockerContext")
 	}
+	if storeMetadata.Name == DefaultContextName {
+		res.Description = "Current DOCKER_HOST based configuration"
+	}
 	return res, nil
 }

cli/command/context/list.go

@@ -44,13 +44,16 @@ func runList(dockerCli command.Cli, opts *listOptions) error {
 	if opts.format == "" {
 		opts.format = formatter.TableFormatKey
 	}
-	curContext := dockerCli.CurrentContext()
 	contextMap, err := dockerCli.ContextStore().List()
 	if err != nil {
 		return err
 	}
-	var contexts []*formatter.ClientContext
+	var (
+		curContext = dockerCli.CurrentContext()
+		contexts   []*formatter.ClientContext
+	)
 	for _, rawMeta := range contextMap {
+		isCurrent := rawMeta.Name == curContext
 		meta, err := command.GetDockerContext(rawMeta)
 		if err != nil {
 			return err
@@ -59,12 +62,9 @@ func runList(dockerCli command.Cli, opts *listOptions) error {
 		if err != nil {
 			return err
 		}
-		if rawMeta.Name == command.DefaultContextName {
-			meta.Description = "Current DOCKER_HOST based configuration"
-		}
 		desc := formatter.ClientContext{
 			Name:           rawMeta.Name,
-			Current:        rawMeta.Name == curContext,
+			Current:        isCurrent,
 			Description:    meta.Description,
 			DockerEndpoint: dockerEndpoint.Host,
 		}
@@ -77,7 +77,7 @@ func runList(dockerCli command.Cli, opts *listOptions) error {
 		return err
 	}
 	if os.Getenv(client.EnvOverrideHost) != "" {
-		fmt.Fprintf(dockerCli.Err(), "Warning: %[1]s environment variable overrides the active context. "+
+		_, _ = fmt.Fprintf(dockerCli.Err(), "Warning: %[1]s environment variable overrides the active context. "+
 			"To use a context, either set the global --context flag, or unset %[1]s environment variable.\n", client.EnvOverrideHost)
 	}
 	return nil

cli/command/context_test.go

@@ -16,7 +16,8 @@ func TestDockerContextMetadataKeepAdditionalFields(t *testing.T) {
 	}
 	jsonBytes, err := json.Marshal(c)
 	assert.NilError(t, err)
-	assert.Equal(t, `{"Description":"test","foo":"bar"}`, string(jsonBytes))
+	const expected = `{"Description":"test","foo":"bar"}`
+	assert.Equal(t, string(jsonBytes), expected)
 
 	var c2 DockerContext
 	assert.NilError(t, json.Unmarshal(jsonBytes, &c2))

cli/context/store/metadatastore.go

@@ -101,7 +101,7 @@ func (s *metadataStore) remove(name string) error {
 func (s *metadataStore) list() ([]Metadata, error) {
 	ctxDirs, err := listRecursivelyMetadataDirs(s.root)
 	if err != nil {
-		if os.IsNotExist(err) {
+		if errors.Is(err, os.ErrNotExist) {
 			return nil, nil
 		}
 		return nil, err
@@ -110,7 +110,7 @@ func (s *metadataStore) list() ([]Metadata, error) {
 	for _, dir := range ctxDirs {
 		c, err := s.getByID(contextdir(dir))
 		if err != nil {
-			if os.IsNotExist(err) {
+			if errors.Is(err, os.ErrNotExist) {
 				continue
 			}
 			return nil, errors.Wrap(err, "failed to read metadata")