feat: add jetstream pull wrappers

components/channel/jetstreamPull.js

@@ -0,0 +1,60 @@
+import { camelCase, getMessageType, realizeParametersForChannelWrapper, renderJSDocParameters, messageHasNullPayload, realizeChannelName} from '../../utils/index';
+// eslint-disable-next-line no-unused-vars
+import { Message, ChannelParameter } from '@asyncapi/parser';
+import { unwrap } from './ChannelParameterUnwrap';
+
+/**
+ * Component which returns a subscribe to function for the client
+ * 
+ * @param {string} defaultContentType 
+ * @param {string} channelName to publish to
+ * @param {Message} message which is being received
+ * @param {Object.<string, ChannelParameter>} channelParameters parameters to the channel
+ */
+export function JetstreamPull(channelName, message, channelParameters) {
+  const messageType = getMessageType(message);
+  let parameters = [];
+  parameters = Object.entries(channelParameters).map(([parameterName]) => {
+    return `${camelCase(parameterName)}Param`;
+  });
+  const hasNullPayload = messageHasNullPayload(message.payload());
+
+  //Determine the callback process when receiving messages.
+  //If the message payload is null no hooks are called to process the received data.
+  let whenReceivingMessage = `onDataCallback(undefined, null ${parameters.length > 0 && `, ${parameters.join(',')}`});`;
+  if (!hasNullPayload) {
+    whenReceivingMessage =  `
+    let receivedData: any = codec.decode(msg.data);
+    onDataCallback(undefined, ${messageType}.unmarshal(receivedData) ${parameters.length > 0 && `, ${parameters.join(',')}`}, msg);
+    `;
+  }
+  return  `
+    /**
+     * Internal functionality to setup jetstrema pull on the \`${channelName}\` channel 
+     * 
+     * @param onDataCallback to call when messages are received
+     * @param js client to pull with
+     * @param codec used to convert messages
+     ${renderJSDocParameters(channelParameters)}
+      */
+    export function jetStreamPull(
+      onDataCallback: (
+        err ? : NatsTypescriptTemplateError,
+        msg ? : ${messageType}
+        ${realizeParametersForChannelWrapper(channelParameters, false)},
+        jetstreamMsg?: Nats.JsMsg) => void,
+      js: Nats.JetStreamClient,
+      codec: Nats.Codec < any >
+      ${realizeParametersForChannelWrapper(channelParameters)},
+    ) {
+      const stream = ${realizeChannelName(channelParameters, channelName)};
+      (async () => {
+        const msg = await js.pull(stream, 'durableName');
+
+        ${unwrap(channelName, channelParameters)}
+
+        ${whenReceivingMessage}
+      })();
+    }
+  `;
+}

components/index/jetstreamPull.js

@@ -0,0 +1,36 @@
+import { camelCase, getMessageType, realizeParametersForChannelWrapper, renderJSDocParameters, realizeParametersForChannelWithoutType, pascalCase} from '../../utils/index';
+
+export function JetstreamPull(channelName, message, messageDescription, channelParameters) {
+  return `
+  /**
+    * JetStream pull function.
+    * 
+    * Pull message from \`${channelName}\`
+    * 
+    * ${messageDescription}
+    * 
+    * @param onDataCallback to call when messages are received
+    ${renderJSDocParameters(channelParameters)}
+    * @param options to pull message with, bindings from the AsyncAPI document overwrite these if specified
+    */
+    public jetStreamPull${pascalCase(channelName)}(
+      onDataCallback: (
+        err ? : NatsTypescriptTemplateError,
+        msg?: ${getMessageType(message)}
+        ${realizeParametersForChannelWrapper(channelParameters, false)},
+        jetstreamMsg?: Nats.JsMsg) => void
+      ${realizeParametersForChannelWrapper(channelParameters)}
+    ): void {
+      if (!this.isClosed() && this.nc !== undefined && this.codec !== undefined && this.js !== undefined) {
+        ${camelCase(channelName)}Channel.jetStreamPull(
+          onDataCallback,
+          this.js,
+          this.codec 
+          ${Object.keys(channelParameters).length ? ` ,${realizeParametersForChannelWithoutType(channelParameters)},` : ''}
+        );
+      } else {
+        throw NatsTypescriptTemplateError.errorForCode(ErrorCode.NOT_CONNECTED);
+      }
+    }
+    `;
+}

examples/simple-subscribe/asyncapi-nats-client/src/channels/StreetlightStreetlightIdCommandTurnon.ts

@@ -53,4 +53,37 @@ export function subscribe(
       reject(NatsTypescriptTemplateError.errorForCode(ErrorCode.INTERNAL_NATS_TS_ERROR, e));
     }
   })
+}
+/**
+ * Internal functionality to setup jetstrema pull on the `streetlight/{streetlight_id}/command/turnon` channel 
+ * 
+ * @param onDataCallback to call when messages are received
+ * @param js client to pull with
+ * @param codec used to convert messages
+ * @param streetlight_id parameter to use in topic
+ */
+export function jetStreamPull(
+  onDataCallback: (
+    err ? : NatsTypescriptTemplateError,
+    msg ? : TurnOn, streetlight_id ? : string,
+    jetstreamMsg ? : Nats.JsMsg) => void,
+  js: Nats.JetStreamClient,
+  codec: Nats.Codec < any > , streetlight_id: string,
+) {
+  const stream = `streetlight.${streetlight_id}.command.turnon`;
+  (async () => {
+    const msg = await js.pull(stream, 'durableName');
+    const unmodifiedChannel = `streetlight.{streetlight_id}.command.turnon`;
+    let channel = msg.subject;
+    const streetlightIdSplit = unmodifiedChannel.split("{streetlight_id}");
+    const splits = [
+      streetlightIdSplit[0],
+      streetlightIdSplit[1]
+    ];
+    channel = channel.substring(splits[0].length);
+    const streetlightIdEnd = channel.indexOf(splits[1]);
+    const streetlightIdParam = "" + channel.substring(0, streetlightIdEnd);
+    let receivedData: any = codec.decode(msg.data);
+    onDataCallback(undefined, TurnOn.unmarshal(receivedData), streetlightIdParam, msg);
+  })();
 }

examples/simple-subscribe/asyncapi-nats-client/src/index.ts

@@ -155,4 +155,31 @@ export class NatsAsyncApiClient {
       }
     });
   }
+  /**
+   * JetStream pull function.
+   * 
+   * Pull message from `streetlight/{streetlight_id}/command/turnon`
+   * 
+   * Channel for the turn on command which should turn on the streetlight
+   * 
+   * @param onDataCallback to call when messages are received
+   * @param streetlight_id parameter to use in topic
+   * @param options to pull message with, bindings from the AsyncAPI document overwrite these if specified
+   */
+  public jetStreamPullStreetlightStreetlightIdCommandTurnon(
+    onDataCallback: (
+      err ? : NatsTypescriptTemplateError,
+      msg ? : TurnOn, streetlight_id ? : string,
+      jetstreamMsg ? : Nats.JsMsg) => void, streetlight_id: string
+  ): void {
+    if (!this.isClosed() && this.nc !== undefined && this.codec !== undefined && this.js !== undefined) {
+      streetlightStreetlightIdCommandTurnonChannel.jetStreamPull(
+        onDataCallback,
+        this.js,
+        this.codec, streetlight_id,
+      );
+    } else {
+      throw NatsTypescriptTemplateError.errorForCode(ErrorCode.NOT_CONNECTED);
+    }
+  }
 }

template/src/channels/$$channel$$.ts.js

@@ -7,6 +7,7 @@ import { General } from '../../../components/channel/general';
 import { pascalCase, isRequestReply, isReplier, isRequester, isPubsub, camelCase} from '../../../utils/index';
 // eslint-disable-next-line no-unused-vars
 import { AsyncAPIDocument, Channel } from '@asyncapi/parser';
+import { JetstreamPull } from '../../../components/channel/jetstreamPull';
 import { JetstreamPublish } from '../../../components/channel/jetstreamPublish';
 
 /**
@@ -70,11 +71,16 @@ function getChannelCode(channel, channelName, params) {
       channelcode = `${publishCode} \n${jetstreamPublishCode}`;
     }
     if (channel.hasPublish()) {
-      channelcode = Subscribe(
+      const normalSubscribeCode = Subscribe(
         channelName, 
         publishMessage, 
         channel.parameters(),
         publishOperation);
+      const jetstreamPullCode = JetstreamPull(
+        channelName, 
+        publishMessage,
+        channel.parameters());
+      channelcode = `${normalSubscribeCode}\n${jetstreamPullCode}`;
     }
   }
   return channelcode;

template/src/index.ts.js

@@ -7,6 +7,7 @@ import { Request } from '../../components/index/request';
 import { isRequestReply, isReplier, isRequester, isPubsub} from '../../utils/index';
 // eslint-disable-next-line no-unused-vars
 import { AsyncAPIDocument } from '@asyncapi/parser';
+import { JetstreamPull } from '../../components/index/jetstreamPull';
 import { JetstreamPublish } from '../../components/index/jetstreamPublish';
 
 /**
@@ -75,11 +76,17 @@ function getChannelWrappers(asyncapi, params) {
         return `${normalPublish} \n ${jetStreamPublish}`;
       }
       if (channel.hasPublish()) {
-        return Subscribe(
+        const normalSubscribeCode = Subscribe(
           channelName, 
           publishMessage, 
           channelDescription, 
           channelParameters);
+        const jetstreamPullCode = JetstreamPull(
+          channelName, 
+          publishMessage, 
+          channelDescription, 
+          channelParameters);
+        return `${normalSubscribeCode}\n${jetstreamPullCode}`;
       }
     }
   });

template/src/testclient/index.ts.js

@@ -7,6 +7,7 @@ import { Request } from '../../../components/index/request';
 import { isRequestReply, isReplier, isRequester, isPubsub} from '../../../utils/index';
 // eslint-disable-next-line no-unused-vars
 import { AsyncAPIDocument, ChannelParameter } from '@asyncapi/parser';
+import { JetstreamPull } from '../../../components/index/jetstreamPull';
 import { JetstreamPublish } from '../../../components/index/jetstreamPublish';
 
 /**
@@ -61,11 +62,17 @@ function getChannelWrappers(asyncapi, params) {
 
     if (isPubsub(channel)) {
       if (channel.hasSubscribe()) {
-        return Subscribe(
+        const normalSubscribeCode = Subscribe(
           channelName, 
           subscribeMessage, 
           channelDescription, 
           channelParameters);
+        const jetstreamPullCode = JetstreamPull(
+          channelName, 
+          subscribeMessage, 
+          channelDescription, 
+          channelParameters);
+        return `${normalSubscribeCode}\n${jetstreamPullCode}`;
       }
       if (channel.hasPublish()) {
         const normalPublish = Publish(

template/src/testclient/testchannels/$$channel$$.ts.js

@@ -7,6 +7,7 @@ import { General } from '../../../../components/channel/general';
 import { pascalCase, isRequestReply, isReplier, isRequester, isPubsub, camelCase} from '../../../../utils/index';
 // eslint-disable-next-line no-unused-vars
 import { AsyncAPIDocument, Channel } from '@asyncapi/parser';
+import { JetstreamPull } from '../../../../components/channel/jetstreamPull';
 import { JetstreamPublish } from '../../../../components/channel/jetstreamPublish';
 
 /**
@@ -58,10 +59,15 @@ function getChannelCode(channel, channelName, params) {
 
   if (isPubsub(channel)) {
     if (channel.hasSubscribe()) {
-      channelcode = Subscribe(
+      const normalSubscribeCode = Subscribe(
         channelName, 
         channel.subscribe() ? channel.subscribe().message(0) : undefined,
         channel.parameters());
+      const jetstreamPullCode = JetstreamPull(
+        channelName, 
+        channel.subscribe() ? channel.subscribe().message(0) : undefined,
+        channel.parameters());
+      channelcode = `${normalSubscribeCode}\n${jetstreamPullCode}`;
     }
     if (channel.hasPublish()) {
       const publishCode = Publish(