first commit

packages/@n8n/nodes-langchain/nodes/memory/MemoryChatRetriever/MemoryChatRetriever.node.ts

@@ -0,0 +1,112 @@
+import type { BaseChatMemory } from '@langchain/community/memory/chat_memory';
+import type { BaseMessage } from '@langchain/core/messages';
+import {
+	NodeConnectionTypes,
+	type IDataObject,
+	type IExecuteFunctions,
+	type INodeExecutionData,
+	type INodeType,
+	type INodeTypeDescription,
+} from 'n8n-workflow';
+
+function simplifyMessages(messages: BaseMessage[]) {
+	const chunkedMessages = [];
+	for (let i = 0; i < messages.length; i += 2) {
+		chunkedMessages.push([messages[i], messages[i + 1]]);
+	}
+
+	const transformedMessages = chunkedMessages.map((exchange) => {
+		const simplified = {
+			[exchange[0]._getType()]: exchange[0].content,
+		};
+
+		if (exchange[1]) {
+			simplified[exchange[1]._getType()] = exchange[1].content;
+		}
+
+		return {
+			json: simplified,
+		};
+	});
+	return transformedMessages;
+}
+
+// This node is deprecated. Use MemoryManager instead.
+export class MemoryChatRetriever implements INodeType {
+	description: INodeTypeDescription = {
+		displayName: 'Chat Messages Retriever',
+		name: 'memoryChatRetriever',
+		icon: 'fa:database',
+		iconColor: 'black',
+		group: ['transform'],
+		hidden: true,
+		version: 1,
+		description: 'Retrieve chat messages from memory and use them in the workflow',
+		defaults: {
+			name: 'Chat Messages Retriever',
+		},
+		codex: {
+			categories: ['AI'],
+			subcategories: {
+				AI: ['Miscellaneous'],
+			},
+			resources: {
+				primaryDocumentation: [
+					{
+						url: 'https://docs.n8n.io/integrations/builtin/cluster-nodes/sub-nodes/n8n-nodes-langchain.memorymanager/',
+					},
+				],
+			},
+		},
+
+		inputs: [
+			NodeConnectionTypes.Main,
+			{
+				displayName: 'Memory',
+				maxConnections: 1,
+				type: NodeConnectionTypes.AiMemory,
+				required: true,
+			},
+		],
+
+		outputs: [NodeConnectionTypes.Main],
+		properties: [
+			{
+				displayName: "This node is deprecated. Use 'Chat Memory Manager' node instead.",
+				type: 'notice',
+				default: '',
+				name: 'deprecatedNotice',
+			},
+			{
+				displayName: 'Simplify Output',
+				name: 'simplifyOutput',
+				type: 'boolean',
+				description: 'Whether to simplify the output to only include the sender and the text',
+				default: true,
+			},
+		],
+	};
+
+	async execute(this: IExecuteFunctions): Promise<INodeExecutionData[][]> {
+		this.logger.debug('Executing Chat Memory Retriever');
+
+		const memory = (await this.getInputConnectionData(NodeConnectionTypes.AiMemory, 0)) as
+			| BaseChatMemory
+			| undefined;
+		const simplifyOutput = this.getNodeParameter('simplifyOutput', 0) as boolean;
+
+		const messages = await memory?.chatHistory.getMessages();
+
+		if (simplifyOutput && messages) {
+			return [simplifyMessages(messages)];
+		}
+
+		const serializedMessages =
+			messages?.map((message) => {
+				const serializedMessage = message.toJSON();
+				return { json: serializedMessage as unknown as IDataObject };
+			}) ?? [];
+
+		return [serializedMessages];
+	}
+}