cli/context/store: simplify error handling, and make it more idiomatic

The package defined various special errors; these errors existed for two reasons;

- being able to distinguish "not found" errors from other errors (as "not found"
  errors can be ignored in various cases).
- to be able to update the context _name_ in the error message after the error
  was created. This was needed in cases where the name was not available at the
  location where the error was produced (e.g. only the "id" was present), and
  the helpers to detect "not found" errors did not support wrapped errors (so
  wrapping the error with a "name" could break logic); a `setContextName` interface
  and corresponding `patchErrContextName()` utility was created for this (which
  was a "creative", but not very standard approach).

This patch:

- Removes the special error-types, replacing them with errdefs definitions (which
  is a more common approach in our code-base to detect error types / classes).
- Removes the internal utilities for error-handling, and deprecates the exported
  utilities (to allow external consumers to adjust their code).
- Some errors have been enriched with detailed information (which may be useful
  for debugging / problem solving).
- Note that in some cases, `patchErrContextName()` was called, but the code
  producing the error would never return a `setContextName` error, so would
  never update the error message.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli/command/cli.go

@@ -28,6 +28,7 @@ import (
 	"github.com/docker/docker/api/types/registry"
 	"github.com/docker/docker/api/types/swarm"
 	"github.com/docker/docker/client"
+	"github.com/docker/docker/errdefs"
 	"github.com/docker/go-connections/tlsconfig"
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
@@ -462,8 +463,8 @@ func resolveContextName(opts *cliflags.CommonOptions, config *configfile.ConfigF
 	}
 	if config != nil && config.CurrentContext != "" {
 		_, err := contextstore.GetMetadata(config.CurrentContext)
-		if store.IsErrContextDoesNotExist(err) {
-			return "", errors.Errorf("Current context %q is not found on the file system, please check your config file at %s", config.CurrentContext, config.Filename)
+		if errdefs.IsNotFound(err) {
+			return "", errors.Errorf("current context %q is not found on the file system, please check your config file at %s", config.CurrentContext, config.Filename)
 		}
 		return config.CurrentContext, err
 	}

cli/command/context/create.go

@@ -10,6 +10,7 @@ import (
 	"github.com/docker/cli/cli/command/formatter/tabwriter"
 	"github.com/docker/cli/cli/context/docker"
 	"github.com/docker/cli/cli/context/store"
+	"github.com/docker/docker/errdefs"
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 )
@@ -127,7 +128,7 @@ func checkContextNameForCreation(s store.Reader, name string) error {
 	if err := store.ValidateContextName(name); err != nil {
 		return err
 	}
-	if _, err := s.GetMetadata(name); !store.IsErrContextDoesNotExist(err) {
+	if _, err := s.GetMetadata(name); !errdefs.IsNotFound(err) {
 		if err != nil {
 			return errors.Wrap(err, "error while getting existing contexts")
 		}

cli/command/context/remove.go

@@ -40,7 +40,7 @@ func RunRemove(dockerCli command.Cli, opts RemoveOptions, names []string) error
 		if name == "default" {
 			errs = append(errs, `default: context "default" cannot be removed`)
 		} else if err := doRemove(dockerCli, name, name == currentCtx, opts.Force); err != nil {
-			errs = append(errs, fmt.Sprintf("%s: %s", name, err))
+			errs = append(errs, err.Error())
 		} else {
 			fmt.Fprintln(dockerCli.Out(), name)
 		}
@@ -54,7 +54,7 @@ func RunRemove(dockerCli command.Cli, opts RemoveOptions, names []string) error
 func doRemove(dockerCli command.Cli, name string, isCurrent, force bool) error {
 	if isCurrent {
 		if !force {
-			return errors.New("context is in use, set -f flag to force remove")
+			return errors.Errorf("context %q is in use, set -f flag to force remove", name)
 		}
 		// fallback to DOCKER_HOST
 		cfg := dockerCli.ConfigFile()

cli/command/context/remove_test.go

@@ -6,8 +6,9 @@ import (
 
 	"github.com/docker/cli/cli/config"
 	"github.com/docker/cli/cli/config/configfile"
-	"github.com/docker/cli/cli/context/store"
+	"github.com/docker/docker/errdefs"
 	"gotest.tools/v3/assert"
+	is "gotest.tools/v3/assert/cmp"
 )
 
 func TestRemove(t *testing.T) {
@@ -18,7 +19,7 @@ func TestRemove(t *testing.T) {
 	_, err := cli.ContextStore().GetMetadata("current")
 	assert.NilError(t, err)
 	_, err = cli.ContextStore().GetMetadata("other")
-	assert.Check(t, store.IsErrContextDoesNotExist(err))
+	assert.Check(t, is.ErrorType(err, errdefs.IsNotFound))
 }
 
 func TestRemoveNotAContext(t *testing.T) {
@@ -38,7 +39,7 @@ func TestRemoveCurrent(t *testing.T) {
 	createTestContext(t, cli, "other")
 	cli.SetCurrentContext("current")
 	err := RunRemove(cli, RemoveOptions{}, []string{"current"})
-	assert.ErrorContains(t, err, "current: context is in use, set -f flag to force remove")
+	assert.ErrorContains(t, err, `context "current" is in use, set -f flag to force remove`)
 }
 
 func TestRemoveCurrentForce(t *testing.T) {

cli/command/context/use_test.go

@@ -11,8 +11,8 @@ import (
 	"github.com/docker/cli/cli/command"
 	"github.com/docker/cli/cli/config"
 	"github.com/docker/cli/cli/config/configfile"
-	"github.com/docker/cli/cli/context/store"
 	"github.com/docker/cli/cli/flags"
+	"github.com/docker/docker/errdefs"
 	"github.com/docker/docker/pkg/homedir"
 	"gotest.tools/v3/assert"
 	is "gotest.tools/v3/assert/cmp"
@@ -47,7 +47,7 @@ func TestUse(t *testing.T) {
 func TestUseNoExist(t *testing.T) {
 	cli := makeFakeCli(t)
 	err := newUseCommand(cli).RunE(nil, []string{"test"})
-	assert.Check(t, store.IsErrContextDoesNotExist(err))
+	assert.Check(t, is.ErrorType(err, errdefs.IsNotFound))
 }
 
 // TestUseDefaultWithoutConfigFile verifies that the CLI does not create

cli/command/defaultcontextstore.go

@@ -1,11 +1,10 @@
 package command
 
 import (
-	"fmt"
-
 	"github.com/docker/cli/cli/context/docker"
 	"github.com/docker/cli/cli/context/store"
 	cliflags "github.com/docker/cli/cli/flags"
+	"github.com/docker/docker/errdefs"
 	"github.com/pkg/errors"
 )
 
@@ -107,7 +106,7 @@ func (s *ContextStoreWithDefault) List() ([]store.Metadata, error) {
 // CreateOrUpdate is not allowed for the default context and fails
 func (s *ContextStoreWithDefault) CreateOrUpdate(meta store.Metadata) error {
 	if meta.Name == DefaultContextName {
-		return errors.New("default context cannot be created nor updated")
+		return errdefs.InvalidParameter(errors.New("default context cannot be created nor updated"))
 	}
 	return s.Store.CreateOrUpdate(meta)
 }
@@ -115,7 +114,7 @@ func (s *ContextStoreWithDefault) CreateOrUpdate(meta store.Metadata) error {
 // Remove is not allowed for the default context and fails
 func (s *ContextStoreWithDefault) Remove(name string) error {
 	if name == DefaultContextName {
-		return errors.New("default context cannot be removed")
+		return errdefs.InvalidParameter(errors.New("default context cannot be removed"))
 	}
 	return s.Store.Remove(name)
 }
@@ -135,7 +134,7 @@ func (s *ContextStoreWithDefault) GetMetadata(name string) (store.Metadata, erro
 // ResetTLSMaterial is not implemented for default context and fails
 func (s *ContextStoreWithDefault) ResetTLSMaterial(name string, data *store.ContextTLSData) error {
 	if name == DefaultContextName {
-		return errors.New("The default context store does not support ResetTLSMaterial")
+		return errdefs.InvalidParameter(errors.New("default context cannot be edited"))
 	}
 	return s.Store.ResetTLSMaterial(name, data)
 }
@@ -143,7 +142,7 @@ func (s *ContextStoreWithDefault) ResetTLSMaterial(name string, data *store.Cont
 // ResetEndpointTLSMaterial is not implemented for default context and fails
 func (s *ContextStoreWithDefault) ResetEndpointTLSMaterial(contextName string, endpointName string, data *store.EndpointTLSData) error {
 	if contextName == DefaultContextName {
-		return errors.New("The default context store does not support ResetEndpointTLSMaterial")
+		return errdefs.InvalidParameter(errors.New("default context cannot be edited"))
 	}
 	return s.Store.ResetEndpointTLSMaterial(contextName, endpointName, data)
 }
@@ -176,29 +175,13 @@ func (s *ContextStoreWithDefault) GetTLSData(contextName, endpointName, fileName
 			return nil, err
 		}
 		if defaultContext.TLS.Endpoints[endpointName].Files[fileName] == nil {
-			return nil, &noDefaultTLSDataError{endpointName: endpointName, fileName: fileName}
+			return nil, errdefs.NotFound(errors.Errorf("TLS data for %s/%s/%s does not exist", DefaultContextName, endpointName, fileName))
 		}
 		return defaultContext.TLS.Endpoints[endpointName].Files[fileName], nil
-
 	}
 	return s.Store.GetTLSData(contextName, endpointName, fileName)
 }
 
-type noDefaultTLSDataError struct {
-	endpointName string
-	fileName     string
-}
-
-func (e *noDefaultTLSDataError) Error() string {
-	return fmt.Sprintf("tls data for %s/%s/%s does not exist", DefaultContextName, e.endpointName, e.fileName)
-}
-
-// NotFound satisfies interface github.com/docker/docker/errdefs.ErrNotFound
-func (e *noDefaultTLSDataError) NotFound() {}
-
-// IsTLSDataDoesNotExist satisfies github.com/docker/cli/cli/context/store.tlsDataDoesNotExist
-func (e *noDefaultTLSDataError) IsTLSDataDoesNotExist() {}
-
 // GetStorageInfo implements store.Store's GetStorageInfo
 func (s *ContextStoreWithDefault) GetStorageInfo(contextName string) store.StorageInfo {
 	if contextName == DefaultContextName {

cli/command/defaultcontextstore_test.go

@@ -8,8 +8,10 @@ import (
 	"github.com/docker/cli/cli/context/docker"
 	"github.com/docker/cli/cli/context/store"
 	cliflags "github.com/docker/cli/cli/flags"
+	"github.com/docker/docker/errdefs"
 	"github.com/docker/go-connections/tlsconfig"
 	"gotest.tools/v3/assert"
+	is "gotest.tools/v3/assert/cmp"
 	"gotest.tools/v3/golden"
 )
 
@@ -153,6 +155,7 @@ func TestErrCreateDefault(t *testing.T) {
 		Metadata: testContext{Bar: "baz"},
 		Name:     "default",
 	})
+	assert.Check(t, is.ErrorType(err, errdefs.IsInvalidParameter))
 	assert.Error(t, err, "default context cannot be created nor updated")
 }
 
@@ -160,6 +163,7 @@ func TestErrRemoveDefault(t *testing.T) {
 	meta := testDefaultMetadata()
 	s := testStore(t, meta, store.ContextTLSData{})
 	err := s.Remove("default")
+	assert.Check(t, is.ErrorType(err, errdefs.IsInvalidParameter))
 	assert.Error(t, err, "default context cannot be removed")
 }
 
@@ -167,5 +171,5 @@ func TestErrTLSDataError(t *testing.T) {
 	meta := testDefaultMetadata()
 	s := testStore(t, meta, store.ContextTLSData{})
 	_, err := s.GetTLSData("default", "noop", "noop")
-	assert.Check(t, store.IsErrTLSDataDoesNotExist(err))
+	assert.Check(t, is.ErrorType(err, errdefs.IsNotFound))
 }