A complete implementation of SMPP v5 protocol, written in golang.

• Message encoding auto-detection
• Multipart SMS automatic splitting and concatenating

Supported encodings:

• GSM 7Bit
• ASCII
• Latin-1
• Cyrillic
• Hebrew
• Shift-JIS
• ISO-2022-JP
• EUC-JP
• EUC-KR
• UCS-2

• Please read the SMPP Specification Version 5 first. pdu is not limited to any value range.
• If you do not like the default conn.go implementation, you can easily replace it.
• Device-specific Caveats

1. smpp-receiver
   SMPP Simple Receiver tool

2. smpp-repl
   SMPP Simple Test tool

1. Connect to the Remote (SMPP server)

   parent, err := net.Dial("tcp", "m2m-device:2775")
   if err != nil {
       panic(err)
   }
   conn = smpp.NewConn(context.Background(), parent)
   conn.WriteTimeout = n * time.Second // set write timeout (optional, default 15 minutes)
   conn.ReadTimeout =  n * time.Second // set read timeout  (optional, default 15 minutes)
   go conn.Watch()                     // start watchdog

2. Handshake

   resp, err := conn.Submit(context.Background(), &pdu.BindTransmitter{
       SystemID:   "your system id",
       Password:   "your password",
       SystemType: "your system type",
       Version:    pdu.SMPPVersion50,
   })
   if err != nil {
       panic(err)
   }
   r := resp.(*pdu.BindTransmitterResp)
   if r.Header.CommandStatus == 0 {
       // start keep-alive
       go conn.EnquireLink(time.Minute, time.Minute)
   }

3. Send Message

   packet := &pdu.SubmitSM{
       SourceAddr: pdu.Address{TON: 1, NPI: 1, No: "00919821"},
       DestAddr:   pdu.Address{TON: 1, NPI: 1, No: "99919821"},
   }
   err := packet.Message.Compose("Hello World!")
   if err != nil {
       panic(err)
   }
   resp, err := conn.Submit(context.Background(), packet)
   if err != nil {
       panic(err)
   }
   resp // submit_sm_resp returns

4. Event loop for receiving messages

   for {
       packet := <-conn.PDU()
       // reply a responsable packet
       if p, ok := packet.(pdu.Responsable); ok {
           err := conn.Send(p.Resp())
           if err != nil {
               fmt.Println(err)
           }
       }
   }

This piece of software is released under the MIT license.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.