first commit

packages/nodes-base/nodes/Amqp/helpers/handleMessage.ts

@@ -0,0 +1,78 @@
+import {
+	deepCopy,
+	type IDeferredPromise,
+	type IRun,
+	type ITriggerFunctions,
+	jsonParse,
+} from 'n8n-workflow';
+import type { EventContext } from 'rhea';
+
+type MessageId = string | number | Buffer | undefined;
+
+interface HandleMessageOptions {
+	lastMessageId: MessageId;
+	pullMessagesNumber: number;
+	jsonConvertByteArrayToString?: boolean;
+	jsonParseBody?: boolean;
+	onlyBody?: boolean;
+	parallelProcessing?: boolean;
+	sleepTime?: number;
+}
+
+export async function handleMessage(
+	this: ITriggerFunctions,
+	context: EventContext,
+	options: HandleMessageOptions,
+): Promise<{ messageId: MessageId } | null> {
+	// No message in the context
+	if (!context.message) {
+		return null;
+	}
+
+	// ignore duplicate message check, don't think it's necessary, but it was in the rhea-lib example code
+	if (context.message.message_id && context.message.message_id === options.lastMessageId) {
+		return null;
+	}
+
+	let data = context.message;
+
+	if (options.jsonConvertByteArrayToString === true && data.body.content !== undefined) {
+		// The buffer is not ready... Stringify and parse back to load it.
+		const cont = deepCopy(data.body.content);
+		data.body = String.fromCharCode.apply(null, cont.data as number[]);
+	}
+
+	if (options.jsonConvertByteArrayToString === true && data.body.content !== undefined) {
+		// The buffer is not ready... Stringify and parse back to load it.
+		const content = deepCopy(data.body.content);
+		data.body = String.fromCharCode.apply(null, content.data as number[]);
+	}
+
+	if (options.jsonParseBody === true) {
+		data.body = jsonParse(data.body as string);
+	}
+	if (options.onlyBody === true) {
+		data = data.body;
+	}
+
+	let responsePromise: IDeferredPromise<IRun> | undefined = undefined;
+	if (!options.parallelProcessing) {
+		responsePromise = this.helpers.createDeferredPromise();
+	}
+	if (responsePromise) {
+		this.emit([this.helpers.returnJsonArray([data as any])], undefined, responsePromise);
+		await responsePromise.promise;
+	} else {
+		this.emit([this.helpers.returnJsonArray([data as any])]);
+	}
+
+	if (!context.receiver?.has_credit()) {
+		setTimeout(
+			() => {
+				context.receiver?.add_credit(options.pullMessagesNumber);
+			},
+			(options.sleepTime as number) || 10,
+		);
+	}
+	return { messageId: context.message.message_id };
+}