refactor(message): convert Extension to return bool

return a boolean instead of an error if an extention is found on a message

message/message.go

 package message
 
 import (
-	"errors"
 	"fmt"
 	"io"
 
@@ -88,11 +87,6 @@ const (
 	RequestFailedContentNotFound = GraphSyncResponseStatusCode(34)
 )
 
-var (
-	// ErrExtensionNotPresent means the looked up extension was not found
-	ErrExtensionNotPresent = errors.New("Extension is missing from this message")
-)
-
 // IsTerminalSuccessCode returns true if the response code indicates the
 // request terminated successfully.
 func IsTerminalSuccessCode(status GraphSyncResponseStatusCode) bool {
@@ -398,15 +392,15 @@ func (gsr GraphSyncRequest) Priority() GraphSyncPriority { return gsr.priority }
 
 // Extension returns the content for an extension on a response, or errors
 // if extension is not present
-func (gsr GraphSyncRequest) Extension(name GraphSyncExtensionName) ([]byte, error) {
+func (gsr GraphSyncRequest) Extension(name GraphSyncExtensionName) ([]byte, bool) {
 	if gsr.extensions == nil {
-		return nil, ErrExtensionNotPresent
+		return nil, false
 	}
 	val, ok := gsr.extensions[string(name)]
 	if !ok {
-		return nil, ErrExtensionNotPresent
+		return nil, false
 	}
-	return val, nil
+	return val, true
 }
 
 // IsCancel returns true if this particular request is being cancelled
@@ -420,14 +414,14 @@ func (gsr GraphSyncResponse) Status() GraphSyncResponseStatusCode { return gsr.s
 
 // Extension returns the content for an extension on a response, or errors
 // if extension is not present
-func (gsr GraphSyncResponse) Extension(name GraphSyncExtensionName) ([]byte, error) {
+func (gsr GraphSyncResponse) Extension(name GraphSyncExtensionName) ([]byte, bool) {
 	if gsr.extensions == nil {
-		return nil, ErrExtensionNotPresent
+		return nil, false
 	}
 	val, ok := gsr.extensions[string(name)]
 	if !ok {
-		return nil, ErrExtensionNotPresent
+		return nil, false
 	}
-	return val, nil
+	return val, true
 
 }

message/message_test.go

@@ -30,13 +30,13 @@ func TestAppendingRequests(t *testing.T) {
 		t.Fatal("Did not add request to message")
 	}
 	request := requests[0]
-	extensionData, err := request.Extension(extensionName)
+	extensionData, found := request.Extension(extensionName)
 	if request.ID() != id ||
 		request.IsCancel() != false ||
 		request.Priority() != priority ||
 		request.Root().String() != root.String() ||
 		!reflect.DeepEqual(request.Selector(), selector) ||
-		err != nil ||
+		!found ||
 		!reflect.DeepEqual(extension.Data, extensionData) {
 		t.Fatal("Did not properly add request to message")
 	}
@@ -61,13 +61,13 @@ func TestAppendingRequests(t *testing.T) {
 		t.Fatal("Did not add request to deserialized message")
 	}
 	deserializedRequest := deserializedRequests[0]
-	extensionData, err = deserializedRequest.Extension(extensionName)
+	extensionData, found = deserializedRequest.Extension(extensionName)
 	if deserializedRequest.ID() != id ||
 		deserializedRequest.IsCancel() != false ||
 		deserializedRequest.Priority() != priority ||
 		deserializedRequest.Root().String() != root.String() ||
 		!reflect.DeepEqual(deserializedRequest.Selector(), selector) ||
-		err != nil ||
+		!found ||
 		!reflect.DeepEqual(extension.Data, extensionData) {
 		t.Fatal("Did not properly deserialize protobuf messages so requests are equal")
 	}
@@ -89,10 +89,10 @@ func TestAppendingResponses(t *testing.T) {
 		t.Fatal("Did not add response to message")
 	}
 	response := responses[0]
-	extensionData, err := response.Extension(extensionName)
+	extensionData, found := response.Extension(extensionName)
 	if response.RequestID() != requestID ||
 		response.Status() != status ||
-		err != nil ||
+		!found ||
 		!reflect.DeepEqual(extension.Data, extensionData) {
 		t.Fatal("Did not properly add response to message")
 	}
@@ -114,10 +114,10 @@ func TestAppendingResponses(t *testing.T) {
 		t.Fatal("Did not add response to message")
 	}
 	deserializedResponse := deserializedResponses[0]
-	extensionData, err = deserializedResponse.Extension(extensionName)
+	extensionData, found = deserializedResponse.Extension(extensionName)
 	if deserializedResponse.RequestID() != response.RequestID() ||
 		deserializedResponse.Status() != response.Status() ||
-		err != nil ||
+		!found ||
 		!reflect.DeepEqual(extensionData, extension.Data) {
 		t.Fatal("Did not properly deserialize protobuf messages so responses are equal")
 	}
@@ -216,13 +216,13 @@ func TestToNetFromNetEquivalency(t *testing.T) {
 		t.Fatal("Did not add request to deserialized message")
 	}
 	deserializedRequest := deserializedRequests[0]
-	extensionData, err := deserializedRequest.Extension(extensionName)
+	extensionData, found := deserializedRequest.Extension(extensionName)
 	if deserializedRequest.ID() != request.ID() ||
 		deserializedRequest.IsCancel() != request.IsCancel() ||
 		deserializedRequest.Priority() != request.Priority() ||
 		deserializedRequest.Root().String() != request.Root().String() ||
 		!reflect.DeepEqual(deserializedRequest.Selector(), request.Selector()) ||
-		err != nil ||
+		!found ||
 		!reflect.DeepEqual(extensionData, extension.Data) {
 		t.Fatal("Did not keep requests when writing to stream and back")
 	}
@@ -237,10 +237,10 @@ func TestToNetFromNetEquivalency(t *testing.T) {
 		t.Fatal("Did not add response to message")
 	}
 	deserializedResponse := deserializedResponses[0]
-	extensionData, err = deserializedResponse.Extension(extensionName)
+	extensionData, found = deserializedResponse.Extension(extensionName)
 	if deserializedResponse.RequestID() != response.RequestID() ||
 		deserializedResponse.Status() != response.Status() ||
-		err != nil ||
+		!found ||
 		!reflect.DeepEqual(extensionData, extension.Data) {
 		t.Fatal("Did not keep responses when writing to stream and back")
 	}

messagequeue/messagequeue_test.go

@@ -209,10 +209,10 @@ func TestProcessingNotification(t *testing.T) {
 			}
 		}
 		firstResponse := message.Responses()[0]
-		extensionData, err := firstResponse.Extension(extensionName)
+		extensionData, found := firstResponse.Extension(extensionName)
 		if responseID != firstResponse.RequestID() ||
 			status != firstResponse.Status() ||
-			err != nil ||
+			!found ||
 			!reflect.DeepEqual(extension.Data, extensionData) {
 			t.Fatal("Send incorrect response")
 		}

network/libp2p_impl_test.go

@@ -133,10 +133,10 @@ func TestMessageSendAndReceive(t *testing.T) {
 		t.Fatal("Did not add response to received message")
 	}
 	receivedResponse := receivedResponses[0]
-	extensionData, err := receivedResponse.Extension(extensionName)
+	extensionData, found := receivedResponse.Extension(extensionName)
 	if receivedResponse.RequestID() != sentResponse.RequestID() ||
 		receivedResponse.Status() != sentResponse.Status() ||
-		err != nil ||
+		!found ||
 		!reflect.DeepEqual(extension.Data, extensionData) {
 		t.Fatal("Sent message responses did not match received message responses")
 	}

requestmanager/utils.go

@@ -27,8 +27,8 @@ func visitToChannel(ctx context.Context, inProgressChan chan types.ResponseProgr
 func metadataForResponses(responses []gsmsg.GraphSyncResponse, ipldBridge ipldbridge.IPLDBridge) map[gsmsg.GraphSyncRequestID]metadata.Metadata {
 	responseMetadata := make(map[gsmsg.GraphSyncRequestID]metadata.Metadata, len(responses))
 	for _, response := range responses {
-		mdRaw, err := response.Extension(gsmsg.ExtensionMetadata)
-		if err != nil {
+		mdRaw, found := response.Extension(gsmsg.ExtensionMetadata)
+		if !found {
 			log.Warningf("Unable to decode metadata in response for request id: %d", response.RequestID())
 			continue
 		}

responsemanager/responsebuilder/responsebuilder_test.go

@@ -66,8 +66,8 @@ func TestMessageBuilding(t *testing.T) {
 		t.Fatal("did not generate completed partial response")
 	}
 
-	response1MetadataRaw, err := response1.Extension(gsmsg.ExtensionMetadata)
-	if err != nil {
+	response1MetadataRaw, found := response1.Extension(gsmsg.ExtensionMetadata)
+	if !found {
 		t.Fatal("Metadata not included in response")
 	}
 	response1Metadata, err := metadata.DecodeMetadata(response1MetadataRaw, ipldBridge)
@@ -83,8 +83,8 @@ func TestMessageBuilding(t *testing.T) {
 	if err != nil || response2.Status() != gsmsg.RequestCompletedFull {
 		t.Fatal("did not generate completed partial response")
 	}
-	response2MetadataRaw, err := response2.Extension(gsmsg.ExtensionMetadata)
-	if err != nil {
+	response2MetadataRaw, found := response2.Extension(gsmsg.ExtensionMetadata)
+	if !found {
 		t.Fatal("Metadata not included in response")
 	}
 	response2Metadata, err := metadata.DecodeMetadata(response2MetadataRaw, ipldBridge)
@@ -100,8 +100,8 @@ func TestMessageBuilding(t *testing.T) {
 	if err != nil || response3.Status() != gsmsg.PartialResponse {
 		t.Fatal("did not generate completed partial response")
 	}
-	response3MetadataRaw, err := response3.Extension(gsmsg.ExtensionMetadata)
-	if err != nil {
+	response3MetadataRaw, found := response3.Extension(gsmsg.ExtensionMetadata)
+	if !found {
 		t.Fatal("Metadata not included in response")
 	}
 	response3Metadata, err := metadata.DecodeMetadata(response3MetadataRaw, ipldBridge)