Merge pull request #3416 from crosbymichael/hard-code-err

Replace hard coded error messages

client.go

@@ -137,7 +137,7 @@ func New(address string, opts ...ClientOpt) (*Client, error) {
 		c.conn, c.connector = conn, connector
 	}
 	if copts.services == nil && c.conn == nil {
-		return nil, errors.New("no grpc connection or services is available")
+		return nil, ErrNoGRPCAndService
 	}
 
 	// check namespace labels for default runtime
@@ -196,7 +196,7 @@ type Client struct {
 // Reconnect re-establishes the GRPC connection to the containerd daemon
 func (c *Client) Reconnect() error {
 	if c.connector == nil {
-		return errors.New("unable to reconnect to containerd, no connector available")
+		return ErrReconnectFailed
 	}
 	c.connMu.Lock()
 	defer c.connMu.Unlock()
@@ -219,7 +219,7 @@ func (c *Client) IsServing(ctx context.Context) (bool, error) {
 	c.connMu.Lock()
 	if c.conn == nil {
 		c.connMu.Unlock()
-		return false, errors.New("no grpc connection available")
+		return false, ErrNoGRPC
 	}
 	c.connMu.Unlock()
 	r, err := c.HealthService().Check(ctx, &grpc_health_v1.HealthCheckRequest{}, grpc.WaitForReady(true))
@@ -350,7 +350,7 @@ func (c *Client) Fetch(ctx context.Context, ref string, opts ...RemoteOpt) (imag
 	}
 
 	if fetchCtx.Unpack {
-		return images.Image{}, errors.New("unpack on fetch not supported, try pull")
+		return images.Image{}, ErrUnpackNotSupported
 	}
 
 	if fetchCtx.PlatformMatcher == nil {
@@ -656,7 +656,7 @@ func (c *Client) Version(ctx context.Context) (Version, error) {
 	c.connMu.Lock()
 	if c.conn == nil {
 		c.connMu.Unlock()
-		return Version{}, errors.New("no grpc connection available")
+		return Version{}, ErrNoGRPC
 	}
 	c.connMu.Unlock()
 	response, err := c.VersionService().Version(ctx, &ptypes.Empty{})

cmd/containerd/command/error.go

@@ -0,0 +1,32 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package command
+
+import (
+	"github.com/pkg/errors"
+)
+
+var (
+	// ErrUnknownLevel is returned when an unknown debugging level is encountered
+	ErrUnknownLevel = errors.New("unknown level")
+	// ErrRegisterAndUnregisterService is returned when both register and unregister flags are specified
+	ErrRegisterAndUnregisterService = errors.New("--register-service and --unregister-service cannot be used together")
+	// ErrEmptyTopic is returned when no topic is provided
+	ErrEmptyTopic = errors.New("topic required to publish event")
+	// ErrEmptyGRCPAddress is returned when the grpc address is empty
+	ErrEmptyGRCPAddress = errors.New("grpc address cannot be empty")
+)

cmd/containerd/command/main.go

@@ -152,7 +152,7 @@ func App() *cli.App {
 			ttrpcAddress = fmt.Sprintf("%s.ttrpc", config.GRPC.Address)
 		)
 		if address == "" {
-			return errors.New("grpc address cannot be empty")
+			return ErrEmptyGRCPAddress
 		}
 		log.G(ctx).WithFields(logrus.Fields{
 			"version":  version.Version,

cmd/containerd/command/publish.go

@@ -51,7 +51,7 @@ var publishCommand = cli.Command{
 		ctx := namespaces.WithNamespace(gocontext.Background(), context.String("namespace"))
 		topic := context.String("topic")
 		if topic == "" {
-			return errors.New("topic required to publish event")
+			return ErrEmptyTopic
 		}
 		payload, err := getEventPayload(os.Stdin)
 		if err != nil {

cmd/containerd/command/service_windows.go

@@ -18,7 +18,6 @@ package command
 
 import (
 	"bytes"
-	"errors"
 	"fmt"
 	"io/ioutil"
 	"log"
@@ -162,7 +161,7 @@ func (h *etwHook) Fire(e *logrus.Entry) error {
 		etype = windows.EVENTLOG_INFORMATION_TYPE
 		eid = eventDebug
 	default:
-		return errors.New("unknown level")
+		return ErrUnknownLevel
 	}
 
 	// If there is additional data, include it as a second string.
@@ -311,7 +310,7 @@ func registerUnregisterService(root string) (bool, error) {
 
 	if unregisterServiceFlag {
 		if registerServiceFlag {
-			return true, errors.New("--register-service and --unregister-service cannot be used together")
+			return true, ErrRegisterAndUnregisterService
 		}
 		return true, unregisterService()
 	}

cmd/ctr/commands/containers/containers.go

@@ -30,7 +30,6 @@ import (
 	"github.com/containerd/containerd/containers"
 	"github.com/containerd/containerd/log"
 	"github.com/containerd/typeurl"
-	"github.com/pkg/errors"
 	"github.com/urfave/cli"
 )
 
@@ -65,17 +64,17 @@ var createCommand = cli.Command{
 		if config {
 			id = context.Args().First()
 			if context.NArg() > 1 {
-				return errors.New("with spec config file, only container id should be provided")
+				return commands.ErrArgConfigFile
 			}
 		} else {
 			id = context.Args().Get(1)
 			ref = context.Args().First()
 			if ref == "" {
-				return errors.New("image ref must be provided")
+				return commands.ErrUnprovidedImageRef
 			}
 		}
 		if id == "" {
-			return errors.New("container id must be provided")
+			return commands.ErrEmptyContainerID
 		}
 		client, ctx, cancel, err := commands.NewClient(context)
 		if err != nil {
@@ -168,7 +167,7 @@ var deleteCommand = cli.Command{
 		}
 
 		if context.NArg() == 0 {
-			return errors.New("must specify at least one container to delete")
+			return commands.ErrDeleteNoneContainer
 		}
 		for _, arg := range context.Args() {
 			if err := deleteContainer(ctx, client, arg, deleteOpts...); err != nil {
@@ -214,7 +213,7 @@ var setLabelsCommand = cli.Command{
 	Action: func(context *cli.Context) error {
 		containerID, labels := commands.ObjectWithLabelArgs(context)
 		if containerID == "" {
-			return errors.New("container id must be provided")
+			return commands.ErrEmptyContainerID
 		}
 		client, ctx, cancel, err := commands.NewClient(context)
 		if err != nil {
@@ -250,7 +249,7 @@ var infoCommand = cli.Command{
 	Action: func(context *cli.Context) error {
 		id := context.Args().First()
 		if id == "" {
-			return errors.New("container id must be provided")
+			return commands.ErrEmptyContainerID
 		}
 		client, ctx, cancel, err := commands.NewClient(context)
 		if err != nil {

cmd/ctr/commands/error.go

@@ -0,0 +1,32 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package commands
+
+import (
+	"github.com/pkg/errors"
+)
+
+var (
+	// ErrArgConfigFile is returned when the configuration for a spec is provided
+	ErrArgConfigFile = errors.New("with spec config file, only container id should be provided")
+	// ErrUnprovidedImageRef is returned when no image reference is provided
+	ErrUnprovidedImageRef = errors.New("image ref must be provided")
+	// ErrEmptyContainerID is returned when no container id is provided
+	ErrEmptyContainerID = errors.New("container id must be provided")
+	// ErrDeleteNoneContainer is returned when no container ids are provided for deletion
+	ErrDeleteNoneContainer = errors.New("must specify at least one container to delete")
+)

error.go

@@ -0,0 +1,32 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package containerd
+
+import (
+	"github.com/pkg/errors"
+)
+
+var (
+	// ErrNoGRPCAndService is returned when no connection or service is available
+	ErrNoGRPCAndService = errors.New("no grpc connection and service is available")
+	// ErrReconnectFailed is returned when no connector is available to reconnect
+	ErrReconnectFailed = errors.New("unable to reconnect to containerd, no connector available")
+	// ErrNoGRPC is returned when no grpc connect is available
+	ErrNoGRPC = errors.New("no grpc connection available")
+	// ErrUnpackNotSupported is returned when a fetch cannot unpack
+	ErrUnpackNotSupported = errors.New("unpack on fetch not supported, try pull")
+)