Add IsHTTPBatch

IsHTTPBatch is a convenience function such that an end user could
determine if a request or response is batch or not, and process it as
such.

Signed-off-by: Mark Mandel <markmandel@google.com>

v2/alias.go

@@ -135,11 +135,14 @@ var (
 	ToMessage = binding.ToMessage
 
 	// Event Creation
+
 	NewEventFromHTTPRequest   = http.NewEventFromHTTPRequest
 	NewEventFromHTTPResponse  = http.NewEventFromHTTPResponse
 	NewEventsFromHTTPRequest  = http.NewEventsFromHTTPRequest
 	NewEventsFromHTTPResponse = http.NewEventsFromHTTPResponse
 	NewHTTPRequestFromEvents  = http.NewHTTPRequestFromEvents
+	NewHTTPRequestFromEvent   = http.NewHTTPRequestFromEvent
+	IsHTTPBatch               = http.IsHTTPBatch
 
 	// HTTP Messages
 

v2/protocol/http/utility.go

@@ -80,3 +80,9 @@ func NewHTTPRequestFromEvents(ctx context.Context, url string, events []event.Ev
 
 	return request, nil
 }
+
+// IsHTTPBatch returns of the current http.Request or http.Response is a batch event operation, by checking the
+// header `Content-Type` value.
+func IsHTTPBatch(header nethttp.Header) bool {
+	return header.Get(ContentType) == event.ApplicationCloudEventsBatchJSON
+}

v2/protocol/http/utility_test.go

@@ -19,6 +19,7 @@ import (
 	"github.com/cloudevents/sdk-go/v2/event"
 	"github.com/cloudevents/sdk-go/v2/test"
 	"github.com/google/uuid"
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
@@ -235,3 +236,14 @@ func TestNewHTTPRequestFromEvents(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, events, result)
 }
+
+func TestIsHTTPBatch(t *testing.T) {
+	header := http.Header{}
+	assert.False(t, IsHTTPBatch(header))
+
+	header.Set(ContentType, event.ApplicationJSON)
+	assert.False(t, IsHTTPBatch(header))
+
+	header.Set(ContentType, event.ApplicationCloudEventsBatchJSON)
+	assert.True(t, IsHTTPBatch(header))
+}