add ?newline= parameter for stdout publisher constructor

publisher/gocloud.go

@@ -2,7 +2,7 @@ package publisher
 
 import (
 	"context"
-	
+
 	"gocloud.dev/pubsub"
 )
 

publisher/publisher.go

@@ -8,7 +8,7 @@ import (
 	"sort"
 	"strings"
 
-	"github.com/aaronland/go-roster"	
+	"github.com/aaronland/go-roster"
 )
 
 type Publisher interface {

publisher/redis.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"net/url"
 
-	"github.com/go-redis/redis/v8"	
+	"github.com/go-redis/redis/v8"
 )
 
 type RedisPublisher struct {

publisher/stdout.go

@@ -2,11 +2,15 @@ package publisher
 
 import (
 	"context"
+	"fmt"
+	"net/url"
 	"os"
+	"strconv"
 )
 
 type StdoutPublisher struct {
 	Publisher
+	apply_newline bool
 }
 
 func init() {
@@ -16,13 +20,36 @@ func init() {
 
 func NewStdoutPublisher(ctx context.Context, uri string) (Publisher, error) {
 
+	u, err := url.Parse(uri)
+
+	if err != nil {
+		return nil, fmt.Errorf("Failed to parse URI, %w", err)
+	}
+
+	q := u.Query()
+
 	pub := &StdoutPublisher{}
 
+	if q.Get("newline") != "" {
+
+		v, err := strconv.ParseBool(q.Get("newline"))
+
+		if err != nil {
+			return nil, fmt.Errorf("Failed to parse ?newline= parameter, %w", err)
+		}
+
+		pub.apply_newline = v
+	}
+
 	return pub, nil
 }
 
 func (pub *StdoutPublisher) Publish(ctx context.Context, msg string) error {
 
+	if pub.apply_newline {
+		msg = fmt.Sprintf("%s\n", msg)
+	}
+
 	os.Stdout.Write([]byte(msg))
 	return nil
 }

publisher/stdout_test.go

@@ -0,0 +1,26 @@
+package publisher
+
+import (
+	"context"
+	"testing"
+)
+
+func TestSdtoutPublisher(t *testing.T) {
+
+	uris := []string{
+		"stdout://",
+		"stdout://?newline=true",
+		"stdout://?newline=false",
+	}
+
+	ctx := context.Background()
+
+	for _, u := range uris {
+
+		_, err := NewPublisher(ctx, u)
+
+		if err != nil {
+			t.Fatalf("Failed to parse '%s', %v", u, err)
+		}
+	}
+}

subscriber/gocloud.go

@@ -44,13 +44,13 @@ func NewGoCloudSubscriber(ctx context.Context, uri string) (Subscriber, error) {
 func (sub *GoCloudSubscriber) Listen(ctx context.Context, msg_ch chan string) error {
 
 	for {
-		
+
 		msg, err := sub.subscription.Receive(ctx)
-		
+
 		if err != nil {
 			return err
 		}
-	
+
 		go msg.Ack()
 
 		msg_ch <- string(msg.Body)