Connection Examples

Using the Frame API

The Frame API provides you with everything you need to get started communicating with a stomp server.

package main

import (
	"errors"
	"github.com/jjware/stomp"
	"log"
	"net"
	"strings"
)

func main() {
	conn, dialErr := net.Dial("tcp", "http://somesite.com:6464")

	if dialErr != nil {
		log.Fatal(dialErr)
	}

	frmConnect := stomp.NewFrame(stomp.CmdConnect, nil)
	frmConnect.Header.Set(stomp.HdrLogin, "username")
	frmConnect.Header.Set(stomp.HdrPasscode, "password")
	frmConnect.Header.Set(stomp.HdrAcceptVersion, "2.0")

	writeErr := frmConnect.Write(conn)

	if writeErr != nil {
		log.Fatal(writeErr)
	}

	frmResponse, readErr := stomp.ReadFrame(conn)

	if readErr != nil {
		log.Fatal(readErr)
	}

	if frmResponse.Command == stomp.CmdError {

		if message, ok := frmResponse.Header[stomp.HdrMessage]; ok {
			log.Fatal(errors.New(strings.Join(message, ":")))
		}
		log.Fatal("unknown error")
	}

	if frmResponse.Command != stomp.CmdConnected {
		log.Fatalf("unexpected frame command: %s", frmResponse.Command)
	}

	// connection established
}

The stomp connection establishment flow is synchronous, so the code hasn't become complicated yet. However, directly writing to and reading from a connection through the Frame API is not thread safe. Invoking Frame::Write concurrently on the same connection may result in malformed frames on the wire. Invoking stomp.ReadFrame concurrently on the same connection may result in errors. Even more specifically, invoking stomp.ReadFrame in succession on the same connection before invoking Close the body of the previously read frame may result in errors.

Using a Handle

A Handle provides thread safe methods for writing frames to and reading frames from a connection. A context with a timeout may be provided to a handle's methods. A Handle can be obtained by calling the stomp.Bind function and passing in the desired connection.

package main

import (
	"context"
	"errors"
	"github.com/jjware/stomp"
	"log"
	"net"
	"strings"
	"time"
)

func main() {
	conn, dialErr := net.Dial("tcp", "http://someuri.com:61614")

	if dialErr != nil {
		log.Fatal(dialErr)
	}
	handle := stomp.Bind(conn)

	frmConnect := stomp.NewFrame(stomp.CmdConnect, nil)
	frmConnect.Header.Set(stomp.HdrLogin, "username")
	frmConnect.Header.Set(stomp.HdrPasscode, "password")
	frmConnect.Header.Set(stomp.HdrAcceptVersion, "2.0")

	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)

	sendErr := handle.Send(ctx, frmConnect)

	if sendErr != nil {
		log.Fatal(sendErr)
	}

	frmResponse, readErr := handle.Receive(ctx)
	cancel()

	if readErr != nil {
		log.Fatal(readErr)
	}

	if frmResponse.Command == stomp.CmdError {

		if message, ok := frmResponse.Header[stomp.HdrMessage]; ok {
			log.Fatal(errors.New(strings.Join(message, ":")))
		}
		log.Fatal("unknown error")
	}

	if frmResponse.Command != stomp.CmdConnected {
		log.Fatalf("unexpected frame command: %s", frmResponse.Command)
	}

	// connection established
}