Move ConvertToPush method to pubsub.go (#512) (#520)

* move convert to push to pubsub.go

* adding new test

* collapse convertToPush in convertPubSub

* increase testing coverage

pkg/pubsub/adapter/adapter.go

@@ -20,11 +20,12 @@ import (
 	"context"
 	"fmt"
 
+	nethttp "net/http"
+
 	"go.opencensus.io/plugin/ochttp"
 	"go.opencensus.io/plugin/ochttp/propagation/b3"
 	"go.opencensus.io/trace"
 	"go.uber.org/zap"
-	nethttp "net/http"
 
 	cloudevents "github.com/cloudevents/sdk-go"
 	"github.com/cloudevents/sdk-go/pkg/cloudevents/transport"
@@ -213,11 +214,6 @@ func (a *Adapter) receive(ctx context.Context, event cloudevents.Event, resp *cl
 		ctx = trace.NewContext(ctx, trace.FromContext(transformedCTX))
 	}
 
-	// If send mode is Push, convert to Pub/Sub Push payload style.
-	if a.SendMode == converters.Push {
-		event = ConvertToPush(ctx, event)
-	}
-
 	// Apply CloudEvent override extensions to the outbound event.
 	for k, v := range a.extensions {
 		event.SetExtension(k, v)

pkg/pubsub/adapter/converters/pubsub.go

@@ -18,11 +18,15 @@ package converters
 
 import (
 	"context"
+	"encoding/json"
+	"time"
 
 	cloudevents "github.com/cloudevents/sdk-go"
 	. "github.com/cloudevents/sdk-go/pkg/cloudevents"
 	cepubsub "github.com/cloudevents/sdk-go/pkg/cloudevents/transport/pubsub"
 	pubsubcontext "github.com/cloudevents/sdk-go/pkg/cloudevents/transport/pubsub/context"
+	"go.uber.org/zap"
+	"knative.dev/pkg/logging"
 
 	"github.com/google/knative-gcp/pkg/apis/events/v1alpha1"
 )
@@ -47,8 +51,36 @@ func convertPubSub(ctx context.Context, msg *cepubsub.Message, sendMode ModeType
 	event.SetExtension("knativecemode", string(sendMode))
 	event.Data = msg.Data
 	event.DataEncoded = true
-	// Attributes are extensions.
-	if msg.Attributes != nil && len(msg.Attributes) > 0 {
+
+	// If send mode is Push, convert to Pub/Sub Push payload style.
+	if sendMode == Push {
+		logger := logging.FromContext(ctx).With(zap.Any("event.id", event.ID()))
+		// set the content type to something that can be handled by codec.go
+		event.SetDataContentType(cloudevents.ApplicationJSON)
+		msg := &pubSubMessage{
+			ID:          event.ID(),
+			Attributes:  msg.Attributes,
+			PublishTime: event.Time(),
+		}
+
+		var raw json.RawMessage
+		if err := event.DataAs(&raw); err != nil {
+			logger.Debugw("Failed to get data as raw json, using as is.", zap.Error(err))
+			// Use data as a byte slice.
+			msg.Data = event.Data
+		} else {
+			// Use data as a raw message.
+			msg.Data = raw
+		}
+
+		if err := event.SetData(&pushMessage{
+			Subscription: tx.Subscription,
+			Message:      msg,
+		}); err != nil {
+			logger.Warnw("Failed to set data.", zap.Error(err))
+		}
+	} else if msg.Attributes != nil && len(msg.Attributes) > 0 {
+		// Attributes are promoted to extensions if send mode is not Push.
 		for k, v := range msg.Attributes {
 			// CloudEvents v1.0 attributes MUST consist of lower-case letters ('a' to 'z') or digits ('0' to '9') as per
 			// the spec. It's not even possible for a conformant transport to allow non-base36 characters.
@@ -57,6 +89,35 @@ func convertPubSub(ctx context.Context, msg *cepubsub.Message, sendMode ModeType
 				event.SetExtension(k, v)
 			}
 		}
+
 	}
 	return &event, nil
 }
+
+// pushMessage represents the format Pub/Sub uses to push events.
+type pushMessage struct {
+	// Subscription is the subscription ID that received this Message.
+	Subscription string `json:"subscription"`
+	// Message holds the Pub/Sub message contents.
+	Message *pubSubMessage `json:"message,omitempty"`
+}
+
+// PubSubMessage matches the inner message format used by Push Subscriptions.
+type pubSubMessage struct {
+	// ID identifies this message. This ID is assigned by the server and is
+	// populated for Messages obtained from a subscription.
+	// This field is read-only.
+	ID string `json:"id,omitempty"`
+
+	// Data is the actual data in the message.
+	Data interface{} `json:"data,omitempty"`
+
+	// Attributes represents the key-value pairs the current message
+	// is labelled with.
+	Attributes map[string]string `json:"attributes,omitempty"`
+
+	// The time at which the message was published. This is populated by the
+	// server for Messages obtained from a subscription.
+	// This field is read-only.
+	PublishTime time.Time `json:"publish_time,omitempty"`
+}

pkg/pubsub/adapter/converters/pubsub_test.go

@@ -18,6 +18,8 @@ package converters
 
 import (
 	"context"
+	"encoding/json"
+	"fmt"
 	"testing"
 
 	"cloud.google.com/go/pubsub"
@@ -50,7 +52,7 @@ func TestConvertCloudPubSub(t *testing.T) {
 			return pubSubCloudEvent(map[string]string{
 				"attribute1": "value1",
 				"attribute2": "value2",
-			})
+			}, "")
 		},
 	}, {
 		name: "upper case attributes",
@@ -66,7 +68,7 @@ func TestConvertCloudPubSub(t *testing.T) {
 			return pubSubCloudEvent(map[string]string{
 				"attribute1": "value1",
 				"attribute2": "value2",
-			})
+			}, "")
 		},
 	}, {
 		name: "only setting valid alphanumeric attribute",
@@ -81,7 +83,50 @@ func TestConvertCloudPubSub(t *testing.T) {
 		wantEventFn: func() *cloudevents.Event {
 			return pubSubCloudEvent(map[string]string{
 				"attribute1": "value1",
-			})
+			}, "")
+		},
+	}, {
+		name: "schema as attribute",
+		message: &cepubsub.Message{
+			Data: []byte("test data"),
+			Attributes: map[string]string{
+				"attribute1": "value1",
+				"attribute2": "value2",
+				"schema":     "schema_val",
+			},
+		},
+		sendMode: Binary,
+		wantEventFn: func() *cloudevents.Event {
+			return pubSubCloudEvent(map[string]string{
+				"attribute1": "value1",
+				"attribute2": "value2",
+			}, "schema_val")
+		},
+	}, {
+		name: "Push mode with non valid alphanumeric attribute",
+		message: &cepubsub.Message{
+			Data: []byte("\"test data\""), // Data passed in quotes for it to be marshalled properly
+			Attributes: map[string]string{
+				"attribute1":        "value1",
+				"Invalid-Attrib#$^": "value2",
+			},
+		},
+		sendMode: Push,
+		wantEventFn: func() *cloudevents.Event {
+			return pushCloudEvent(map[string]string{
+				"attribute1":        "value1",
+				"Invalid-Attrib#$^": "value2",
+			}, "\"test data\"")
+		},
+	}, {
+		name: "Push mode with no attributes",
+		message: &cepubsub.Message{
+			Data:       []byte("\"test data\""), // Data passed in quotes for it to be marshalled properly
+			Attributes: map[string]string{},
+		},
+		sendMode: Push,
+		wantEventFn: func() *cloudevents.Event {
+			return pushCloudEvent(nil, "\"test data\"")
 		},
 	}}
 
@@ -98,7 +143,6 @@ func TestConvertCloudPubSub(t *testing.T) {
 			))
 
 			gotEvent, err := Convert(ctx, test.message, test.sendMode, "")
-
 			if err != nil {
 				if !test.wantErr {
 					t.Errorf("converters.convertPubsub got error %v want error=%v", err, test.wantErr)
@@ -112,7 +156,7 @@ func TestConvertCloudPubSub(t *testing.T) {
 	}
 }
 
-func pubSubCloudEvent(extensions map[string]string) *cloudevents.Event {
+func pubSubCloudEvent(extensions map[string]string, schema string) *cloudevents.Event {
 	e := cloudevents.NewEvent(cloudevents.VersionV1)
 	e.SetID("id")
 	e.SetSource(v1alpha1.CloudPubSubSourceEventSource("testproject", "testtopic"))
@@ -124,5 +168,26 @@ func pubSubCloudEvent(extensions map[string]string) *cloudevents.Event {
 	for k, v := range extensions {
 		e.SetExtension(k, v)
 	}
+	if schema != "" {
+		e.SetDataSchema(schema)
+	}
+	return &e
+}
+
+func pushCloudEvent(attributes map[string]string, data string) *cloudevents.Event {
+	e := cloudevents.NewEvent(cloudevents.VersionV1)
+	e.SetID("id")
+	e.SetSource(v1alpha1.CloudPubSubSourceEventSource("testproject", "testtopic"))
+	e.SetDataContentType(cloudevents.ApplicationJSON)
+	e.SetType(v1alpha1.CloudPubSubSourcePublish)
+	e.SetExtension("knativecemode", string(Push))
+	at := ""
+	if attributes != nil {
+		ex, _ := json.Marshal(attributes)
+		at = fmt.Sprintf(`"attributes":%s,`, ex)
+	}
+	s := fmt.Sprintf(`{"subscription":"testsubscription","message":{"id":"id","data":%s,%s"publish_time":"0001-01-01T00:00:00Z"}}`, data, at)
+	e.Data = []byte(s)
+	e.DataEncoded = true
 	return &e
 }