Refactor processors to reduce duplicate code

src/PDUProcessor/PduProcessor.ts

@@ -6,12 +6,26 @@ export default abstract class PduProcessor {
 	readonly sessionType: string;
 	readonly name: string = this.constructor.name;
 	readonly logger: Logger = new Logger(`PduProcessor: ${this.name}`);
+	abstract applicableCommands: string[];
 
 	constructor(type: string) {
 		this.sessionType = type;
 	}
 
-	abstract processPdu(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any>;
+	protected pduDoesApply(pdu: any): boolean {
+		if (pdu.command) {
+			return this.applicableCommands.includes(pdu.command);
+		}
+		return false;
+	}
+
+	protected abstract doProcess(session: any, pdu: any, entity?: SmppSession | undefined): any;
+
+	processPdu(session: any, pdu: any, entity?: SmppSession | undefined): any {
+		if (this.pduDoesApply(pdu)) {
+			return this.doProcess(session, pdu, entity);
+		}
+	}
 
 	serialize(): object {
 		return {

src/PDUProcessor/Postprocessor/Center/BindTranscieverReplyProcessor.ts

@@ -4,18 +4,19 @@ import Postprocessor from "../Postprocessor";
 const smpp = require("smpp");
 
 export default class BindTranscieverReplyProcessor extends Postprocessor {
+	applicableCommands: string[] = ['bind_transceiver'];
+
 	constructor(type: string) {
 		super(type);
 	}
 
-	processPdu(session: any, pdu: any, entity?: Center | undefined): Promise<any> {
+	doProcess(session: any, pdu: any, entity?: Center | undefined): Promise<any> {
 		return new Promise((resolve, reject) => {
-			if (!!pdu.command && pdu.command === 'bind_transceiver') {
 			if (!entity) {
 				reject();
 			}
 
-				this.logger.log1(`Center-${entity?.id} got a bind_transciever with system_id ${pdu.system_id} and password ${pdu.password}`);
+			this.logger.log1(`Center-${entity?.id} got a bind_transceiver with system_id ${pdu.system_id} and password ${pdu.password}`);
 			session.pause();
 			if (pdu.system_id === entity?.username && pdu.password === entity?.password) {
 				this.logger.log1(`Center-${entity?.id} client connection successful`);
@@ -39,7 +40,6 @@ export default class BindTranscieverReplyProcessor extends Postprocessor {
 				entity?.updateStatus();
 				session.close();
 			}
-			}
 		});
 	}
 }

src/PDUProcessor/Postprocessor/Center/DeliveryReceiptProcessor.ts

@@ -5,13 +5,14 @@ import Postprocessor from "../Postprocessor";
 const smpp = require("smpp");
 
 export default class DeliveryReceiptProcessor extends Postprocessor {
+    applicableCommands: string[] = ['submit_sm'];
 	constructor(type: string) {
 		super(type);
 	}
 
-	processPdu(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
+	protected doProcess(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise<any>((resolve, reject) => {
-			if (!!pdu.command && pdu.command === "submit_sm" && pdu.registered_delivery) {
+			if (pdu.registered_delivery) {
 				let drMessage: string = "";
 				let date: string = new Date().toISOString().replace(/T/, '').replace(/\..+/, '').replace(/-/g, '').replace(/:/g, '').substring(2, 12);
 
@@ -39,8 +40,4 @@ export default class DeliveryReceiptProcessor extends Postprocessor {
 			}
 		});
 	}
-
-	private padLeft(str: string, pad: string, length: number): string {
-		return (new Array(length + 1).join(pad) + str).slice(-length);
-	}
 }

src/PDUProcessor/Postprocessor/Center/EchoPduProcessor.ts

@@ -4,13 +4,15 @@ import Postprocessor from "../Postprocessor";
 const smpp = require("smpp");
 
 export default class EchoPduProcessor extends Postprocessor {
+    applicableCommands: string[] = ['submit_sm'];
 	constructor(type: string) {
 		super(type);
 	}
 
-	processPdu(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
+	protected doProcess(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise<any>((resolve, reject) => {
-			if (!!pdu.command && pdu.command === "submit_sm" && !pdu.short_message.udh) {
+			// Temporary (?) safeguard against echoing long sms
+			if (!pdu.short_message.udh) {
 				let echoPdu = new smpp.PDU('deliver_sm', {...pdu});
 				echoPdu.source_addr = pdu.destination_addr;
 				echoPdu.destination_addr = pdu.source_addr;

src/PDUProcessor/Postprocessor/Center/EnquireLinkReplyProcessor.ts

@@ -2,16 +2,16 @@ import SmppSession from "../../../SmppSession";
 import Postprocessor from "../Postprocessor";
 
 export default class EnquireLinkReplyProcessor extends Postprocessor {
+	applicableCommands: string[] = ['enquire_link'];
+
 	constructor(type: string) {
 		super(type);
 	}
 
-	processPdu(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
+	protected doProcess(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise((resolve, reject) => {
-			if (!!pdu.command && pdu.command === 'enquire_link') {
 			entity?.doSendPdu(pdu.response(), session);
 			resolve(pdu);
-			}
 		});
 	}
 }

src/PDUProcessor/Postprocessor/Center/SubmitSmReplyProcessor.ts

@@ -3,22 +3,20 @@ import SmppSession from "../../../SmppSession";
 import Postprocessor from "../Postprocessor";
 
 export default class SubmitSmReplyProcessor extends Postprocessor {
+	applicableCommands: string[] = ['submit_sm'];
 	private messageIdIterator: number = 0;
 
 	constructor(type: string) {
 		super(type);
 	}
 
-	processPdu(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
+	protected doProcess(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise((resolve, reject) => {
-			if (!!pdu.command && pdu.command === 'submit_sm') {
-				// Add an ID here!
 			let response = pdu.response();
 			response.message_id = this.messageIdIterator++;
 			MessageIdManager.addMessageId(pdu, response.message_id);
 			entity?.doSendPdu(response, session);
 			resolve(pdu);
-			}
 		});
 	}
 }

src/PDUProcessor/Postprocessor/Client/DeliverSmReplyProcessor.ts

@@ -2,16 +2,16 @@ import SmppSession from "../../../SmppSession";
 import Postprocessor from "../Postprocessor";
 
 export default class DeliverSmReplyProcessor extends Postprocessor {
+	applicableCommands: string[] = ['deliver_sm'];
+
 	constructor(type: string) {
 		super(type);
 	}
 
-	processPdu(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
+	protected doProcess(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise((resolve, reject) => {
-			if (!!pdu.command && pdu.command === 'deliver_sm') {
 			entity?.doSendPdu(pdu.response(), session);
 			resolve(pdu);
-			}
 		});
 	}
 }

src/PDUProcessor/Preprocessor/Client/DeliveryReceiptRequestProcessor.ts

@@ -2,17 +2,15 @@ import SmppSession from "../../../SmppSession";
 import Preprocessor from "../Preprocessor";
 
 export default class DeliveryReceiptRequestProcessor extends Preprocessor {
-	private iterator: number = 0;
+	applicableCommands: string[] = ['submit_sm'];
 
 	constructor(type: string) {
 		super(type);
 	}
 
-	processPdu(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
+	protected doProcess(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise<any>((resolve, reject) => {
-			if (!!pdu.command && pdu.command === "submit_sm") {
 			pdu.registered_delivery = 1;
-			}
 		});
 	}
 }

src/PDUProcessor/Preprocessor/Client/DestinationEnumeratorProcessor.ts

@@ -2,13 +2,14 @@ import SmppSession from "../../../SmppSession";
 import Preprocessor from "../Preprocessor";
 
 export default class DestinationEnumeratorProcessor extends Preprocessor {
+    applicableCommands: string[] = ['submit_sm', 'deliver_sm'];
 	private iterator: number = 0;
 
 	constructor(type: string) {
 		super(type);
 	}
 
-	processPdu(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
+	protected doProcess(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise<any>((resolve, reject) => {
 			if (!!pdu.destination_addr) {
 				pdu.destination_addr = pdu.destination_addr + this.padLeft(String(this.iterator++), '0', 5);

src/PDUProcessor/Preprocessor/Client/LongSmsProcessor.ts

@@ -5,6 +5,7 @@ import Preprocessor from "../Preprocessor";
 const smpp = require('smpp');
 
 export default class LongSmsProcessor extends Preprocessor {
+    applicableCommands: string[] = ['submit_sm', 'deliver_sm'];
 	static readonly maxMessageSizeBits = 1072;
 	private iterator: number = 0;
 
@@ -47,7 +48,7 @@ export default class LongSmsProcessor extends Preprocessor {
 		return characterSizeBits;
 	}
 
-	processPdu(session: any, pdu: PDU, entity?: SmppSession | undefined): Promise<any> {
+	protected doProcess(session: any, pdu: PDU, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise<any>((resolve, reject) => {
 			if (!!pdu.short_message) {
 				let characterSizeBits: number = LongSmsProcessor.getCharacterSizeForEncoding(pdu);

src/PDUProcessor/Preprocessor/Client/SourceEnumeratorProcessor.ts

@@ -2,13 +2,14 @@ import SmppSession from "../../../SmppSession";
 import Preprocessor from "../Preprocessor";
 
 export default class SourceEnumeratorProcessor extends Preprocessor {
+	applicableCommands: string[] = ['submit_sm', 'deliver_sm'];
 	private iterator: number = 0;
 
 	constructor(type: string) {
 		super(type);
 	}
 
-	processPdu(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
+	protected doProcess(session: any, pdu: any, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise<any>((resolve, reject) => {
 			if (!!pdu.source_addr) {
 				pdu.source_addr = pdu.source_addr + this.padLeft(String(this.iterator++), '0', 5);