snapshot of https://github.com/ThreeDotsLabs/watermill.git (master, 2026-09-15; blobs > 131072B omitted)

tools/mill/cmd/consume.go

@@ -0,0 +1,70 @@
+package cmd
+
+import (
+	"context"
+	"os"
+	"time"
+
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+
+	"github.com/ThreeDotsLabs/watermill-io/pkg/io"
+	"github.com/ThreeDotsLabs/watermill/message"
+	"github.com/ThreeDotsLabs/watermill/message/router/plugin"
+)
+
+// consumer is initialized by the parent command to the pub/sub provider of choice.
+var consumer message.Subscriber
+
+func addConsumeCmd(parent *cobra.Command, topicKey string) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "consume",
+		Short: "Consume messages from a pub/sub and print them to stdout",
+		Long: `Consume messages from the pub/sub of your choice and print them on the standard output.
+
+For the configuration of particular pub/sub providers, see the help for the provider commands.`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			topic := viper.GetString(topicKey)
+			router, err := message.NewRouter(
+				message.RouterConfig{
+					CloseTimeout: 5 * time.Second,
+				},
+				logger,
+			)
+			if err != nil {
+				return errors.Wrap(err, "could not create router")
+			}
+
+			router.AddPlugin(plugin.SignalsHandler)
+
+			out, err := io.NewPublisher(
+				os.Stdout,
+				io.PublisherConfig{
+					MarshalFunc: io.PayloadMarshalFunc,
+				},
+				logger,
+			)
+			if err != nil {
+				return errors.Wrap(err, "could not create console producer")
+			}
+
+			router.AddHandler(
+				"dump_to_stdout",
+				topic,
+				consumer,
+				"",
+				out,
+				func(msg *message.Message) ([]*message.Message, error) {
+					// just forward the message to stdout
+					return message.Messages{msg}, nil
+				},
+			)
+
+			return router.Run(context.Background())
+		},
+	}
+
+	parent.AddCommand(cmd)
+	return cmd
+}