we have a message campaign where we send over 100k messages (SMS) a day. So we are a client of SMSC server. We have no influence on SMSC server code. Before some time, we had around 80-90 message per second, now frequency dropped to 15 messages per second, according to tcpdumps.
I have few information regarding this, so I will try to explain best as I can.
So we are using Spring Boot 2.7 and open source jsmpp (3.0.0) library for sending SMS messages (PDU commands) to SMSC.
While reading about protocol (page 40), I noticed that there is a way to send messages asynchronously by providing a seqence_number. The code example is here. But I am not sure if that is going to help...
The code:
@Component
public class ClientConfig {
@Autowired
private MessageReceiverListener msgListener;
@Autowired
private SessionStateListener sessionListener;
private SMPPSession session;
public String charset = "ISO-10646-UCS-2";
public long idleReceiveTimeout = 65000;
public long checkBindingTimeout = 12000;
public long timeout = 7000;
public int enquireLinkTimeout = 15000;
public String hostIp = "someIpAddress";
public int port = 5000;
public String final systemId = "someSystemId";
public String final password = "password";
public BindType bindType = BindType.BIND_TRX; //transceiver
public String systemType = null;
public String addressRange = null;
public TypeOfNumber addrTon = TypeOfNumber.UNKNOWN;
public NumberingPlanIndicator addrNpi = NumberingPlanIndicator.UNKNOWN;
protected synchronized void tryToConnectToSmsc() throws Exception {
try {
// Connect to host
BindParameter bp = new BindParameter(bindType, systemId, password, systemType, addrTon, addrNpi, addressRange);
session = new SMPPSession();
session.setEnquireLinkTimer(enquireLinkTimer);
session.connectAndBind(host, port, bp, timeout);
session.setMessageReceiverListener(msgListener);
session.addSessionStateListener(sessionListener);
}
// Main connection failed.
catch (Exception e) {
//log and re-attempt connection logic here
}
}
}
The listeners:
@Component
public class MySessionListenerImpl implements SessionStateListener {
@Override
public void onStateChange(SessionState newState, SessionState oldState, Session source) {
//TODO
}
}
@Service
public class SmsListenerImpl implements MessageReceiverListener {
@Override
public void onAcceptDeliverSm(DeliverSm deliverSm) throws ProcessRequestException {
//TODO
}
@Override
public void onAcceptAlertNotification(AlertNotification alertNotification) {}
@Override
public DataSmResult onAcceptDataSm(DataSm dataSm, Session session) throws ProcessRequestException {
return null;
}
}
Message sending service:
@Service
public class MessageSendingServiceImpl extends ClientConfig implements MessageSendingService{
private final ESMClass esmClass = new ESMClass();
private final byte protocolId = (byte) 0;
private final byte priorityFlag = (byte) 1;
private final TimeFormatter formatter = new AbsoluteTimeFormatter();
private final byte defaultMsgId = (byte) 0;
public SmsAdapterServiceImpl() {
super();
}
@PostConstruct
public synchronized void init() throws Exception {
super.tryToConnectToSmsc();
}
@Override
public String send(DomainObject obj){ //DomainObject -> contains fields: id, to, from, text, delivery, validity;
String serviceType = null;
//source
TypeOfNumber sourceTON = TypeOfNumber.NATIONAL; //there is some logic here which determines if it is INTERNATIOANL, ALPHANUMERIC etc...
NumberPlaningIndicator sourceNpi = NumberPlaningIndicator.ISDN; //constant...
String sourcePhone = obj.getFrom();
//destination
TypeOfNumber destinationTON = TypeOfNumber.NATIONAL; //there is some logic here which determines if it is INTERNATIOANL, ALPHANUMERIC etc...
NumberPlaningIndicator destinationNpi = NumberPlaningIndicator.ISDN; //constant...
String destinationPhone = obj.getTo();
String scheduledDeliveryTime = null;
if (obj.getDelivery() != null) scheduledDeliveryTime = formatter.format(obj.getDelivery());
String validityPeriodTime = null;
if (obj.getValidity() != null) validityPeriodTime = formatter.format(obj.getValidity());
Map<Short, OptionalParameter> optionalParameters = new HashMap<>();
String text = obj.getText();
if ( text.length() > 89 ) { //set text as payload instead of message text
OctetString os = new OctetString(OptionalParameter.Tag.MESSAGE_PAYLOAD.code(), text, "ISO-10646-UCS-2"); //"ISO-10646-UCS-2" - encoding
optionalParameters.put(os.tag, os);
text = "";
}
String msgId =
session.submitShortMessage( serviceType ,
sourceTON ,
sourceNpi ,
sourcePhone ,
destinationTON ,
destinationNpi ,
destinationPhone ,
esmClass ,
protocolId ,
priorityFlag ,
scheduledDeliveryTime ,
validityPeriodTime ,
new RegisteredDelivery() ,
ReplaceIfPresentFlag.DEFAULT.value() ,
new GeneralDataCoding(Alphabet.ALPHA_UCS2) ,
defaultMsgId ,
text.getBytes("ISO-10646-UCS-2") ,
optionalParameters.values().toArray(new OptionalParameter[0]));
return msgId;
}
}
Client code which invokes the service (it is actually a scheduler job):
@Autowired private MessageSendingService messageSendingService;
@Scheduled(cron)
public void execute() {
List<DomainObject> messages = repository.findMessages(pageable, config.getBatch()); //up to several thousand
start(messages);
ThreadPoolExecutor executorService = (ThreadPoolExecutor) Executors.newFixedThreadPool(getSchedulerConfiguration().getPoolSize(), new NamedThreadFactory("Factory"));
List<DomainObject> domainObjects = Collections.synchronizedList(messages);
List<List<DomainObject>> domainObjectsPartitioned = partition(domainObjects.size(), config.getPoolSize()); //pool size is 4
for (List<DomainObject> list: domainObjectsPartitioned ) {
executorService.execute(new Runnable() {
@Override
public void run() {
try {
start(list);
} catch (Exception e) {
e.printStackTrace();
}
});
}
executorService.shutdown();
}
}
private void start(List<DomainObject> list){
for (DomainObject> obj : list) {
String mid = messageSendingService.send(obj);
//do smtg with id...
}
}
