feat(Truefoundry Chat Model Node): Add Truefoundry AI Gateway integration

packages/@n8n/nodes-langchain/credentials/TruefoundryApi.credentials.ts

@@ -0,0 +1,92 @@
+import type {
+	ICredentialDataDecryptedObject,
+	ICredentialTestRequest,
+	ICredentialType,
+	IHttpRequestOptions,
+	INodeProperties,
+} from 'n8n-workflow';
+
+export class TruefoundryApi implements ICredentialType {
+	name = 'truefoundryAiGatewayApi';
+
+	displayName = 'TrueFoundry';
+
+	documentationUrl = 'truefoundry';
+
+	properties: INodeProperties[] = [
+		{
+			displayName: 'API Key',
+			name: 'apiKey',
+			type: 'string',
+			typeOptions: { password: true },
+			required: true,
+			default: '',
+		},
+		{
+			displayName: 'Base URL',
+			name: 'url',
+			type: 'string',
+			default: 'https://gateway.truefoundry.com',
+			description: 'Override the default base URL for the API',
+		},
+		{
+			displayName: 'Add Custom Header',
+			name: 'header',
+			type: 'boolean',
+			default: false,
+		},
+		{
+			displayName: 'Header Name',
+			name: 'headerName',
+			type: 'string',
+			displayOptions: {
+				show: {
+					header: [true],
+				},
+			},
+			default: '',
+		},
+		{
+			displayName: 'Header Value',
+			name: 'headerValue',
+			type: 'string',
+			typeOptions: {
+				password: true,
+			},
+			displayOptions: {
+				show: {
+					header: [true],
+				},
+			},
+			default: '',
+		},
+	];
+
+	test: ICredentialTestRequest = {
+		request: {
+			baseURL: '={{$credentials?.url}}',
+			url: '/models',
+		},
+	};
+
+	async authenticate(
+		credentials: ICredentialDataDecryptedObject,
+		requestOptions: IHttpRequestOptions,
+	): Promise<IHttpRequestOptions> {
+		requestOptions.headers ??= {};
+
+		requestOptions.headers['Authorization'] = `Bearer ${credentials.apiKey}`;
+
+		// Add custom headers if configured
+		if (
+			credentials.header &&
+			typeof credentials.headerName === 'string' &&
+			credentials.headerName &&
+			typeof credentials.headerValue === 'string'
+		) {
+			requestOptions.headers[credentials.headerName] = credentials.headerValue;
+		}
+
+		return requestOptions;
+	}
+}

packages/@n8n/nodes-langchain/nodes/llms/LmChatTruefoundry/LmChatTruefoundry.node.ts

@@ -0,0 +1,303 @@
+import { ChatOpenAI, type ClientOptions } from '@langchain/openai';
+import pick from 'lodash/pick';
+import {
+	NodeConnectionTypes,
+	type INodeType,
+	type INodeTypeDescription,
+	type ISupplyDataFunctions,
+	type SupplyData,
+} from 'n8n-workflow';
+
+import { getProxyAgent } from '@utils/httpProxyAgent';
+import { getConnectionHintNoticeField } from '@utils/sharedFields';
+
+import { searchModels } from './methods/loadModels';
+import { openAiFailedAttemptHandler } from '../../vendors/OpenAi/helpers/error-handling';
+import { makeN8nLlmFailedAttemptHandler } from '../n8nLlmFailedAttemptHandler';
+import { N8nLlmTracing } from '../N8nLlmTracing';
+
+export class LmChatTruefoundry implements INodeType {
+	methods = {
+		listSearch: {
+			searchModels,
+		},
+	};
+
+	description: INodeTypeDescription = {
+		displayName: 'Truefoundry Chat Model',
+
+		name: 'lmChatTruefoundry',
+		icon: { light: 'file:truefoundry.svg', dark: 'file:truefoundry.dark.svg' },
+		group: ['transform'],
+		version: [1],
+		description: 'For advanced usage with an AI chain',
+		defaults: {
+			name: 'Truefoundry Chat Model',
+		},
+		codex: {
+			categories: ['AI'],
+			subcategories: {
+				AI: ['Language Models', 'Root Nodes'],
+				'Language Models': ['Chat Models (Recommended)'],
+			},
+			resources: {
+				primaryDocumentation: [
+					{
+						url: 'https://docs.n8n.io/integrations/builtin/cluster-nodes/sub-nodes/n8n-nodes-langchain.lmchattruefoundry/',
+					},
+				],
+			},
+		},
+
+		inputs: [],
+
+		outputs: [NodeConnectionTypes.AiLanguageModel],
+		outputNames: ['Model'],
+		credentials: [
+			{
+				name: 'truefoundryAiGatewayApi',
+				required: true,
+			},
+		],
+		properties: [
+			getConnectionHintNoticeField([NodeConnectionTypes.AiChain, NodeConnectionTypes.AiAgent]),
+			{
+				displayName:
+					'If using JSON response format, you must include word "json" in the prompt in your chain or agent. Also, make sure to select latest models released post November 2023.',
+				name: 'notice',
+				type: 'notice',
+				default: '',
+				displayOptions: {
+					show: {
+						'/options.responseFormat': ['json_object'],
+					},
+				},
+			},
+			{
+				displayName: 'Model',
+				name: 'model',
+				type: 'resourceLocator',
+				default: { mode: 'list', value: '' },
+				required: true,
+				modes: [
+					{
+						displayName: 'From List',
+						name: 'list',
+						type: 'list',
+						placeholder: 'Select a model...',
+						typeOptions: {
+							searchListMethod: 'searchModels',
+							searchable: true,
+						},
+					},
+					{
+						displayName: 'ID',
+						name: 'id',
+						type: 'string',
+						placeholder: 'provider-name/model-name',
+					},
+				],
+				description: 'The model. Choose from the list, or specify an ID.',
+			},
+			{
+				displayName: 'Options',
+				name: 'options',
+				placeholder: 'Add Option',
+				description: 'Additional options to add',
+				type: 'collection',
+				default: {},
+				options: [
+					{
+						displayName: 'Frequency Penalty',
+						name: 'frequencyPenalty',
+						default: 0,
+						typeOptions: { maxValue: 2, minValue: -2, numberPrecision: 1 },
+						description:
+							"Positive values penalize new tokens based on their existing frequency in the text so far, decreasing the model's likelihood to repeat the same line verbatim",
+						type: 'number',
+					},
+					{
+						displayName: 'Maximum Number of Tokens',
+						name: 'maxTokens',
+						default: -1,
+						description:
+							'The maximum number of tokens to generate in the completion. Most models have a context length of 2048 tokens (except for the newest models, which support 32,768).',
+						type: 'number',
+						typeOptions: {
+							maxValue: 32768,
+						},
+					},
+					{
+						displayName: 'Response Format',
+						name: 'responseFormat',
+						default: 'text',
+						type: 'options',
+						options: [
+							{
+								name: 'Text',
+								value: 'text',
+								description: 'Regular text response',
+							},
+							{
+								name: 'JSON',
+								value: 'json_object',
+								description:
+									'Enables JSON mode, which should guarantee the message the model generates is valid JSON',
+							},
+						],
+					},
+					{
+						displayName: 'Presence Penalty',
+						name: 'presencePenalty',
+						default: 0,
+						typeOptions: { maxValue: 2, minValue: -2, numberPrecision: 1 },
+						description:
+							"Positive values penalize new tokens based on whether they appear in the text so far, increasing the model's likelihood to talk about new topics",
+						type: 'number',
+					},
+					{
+						displayName: 'Sampling Temperature',
+						name: 'temperature',
+						default: 0.7,
+						typeOptions: { maxValue: 2, minValue: 0, numberPrecision: 1 },
+						description:
+							'Controls randomness: Lowering results in less random completions. As the temperature approaches zero, the model will become deterministic and repetitive.',
+						type: 'number',
+					},
+					{
+						displayName: 'Timeout',
+						name: 'timeout',
+						default: 360000,
+						description: 'Maximum amount of time a request is allowed to take in milliseconds',
+						type: 'number',
+					},
+					{
+						displayName: 'Max Retries',
+						name: 'maxRetries',
+						default: 2,
+						description: 'Maximum number of retries to attempt',
+						type: 'number',
+					},
+					{
+						displayName: 'Reasoning Effort',
+						name: 'reasoningEffort',
+						default: 'medium',
+						description:
+							'Controls the amount of reasoning tokens to use. A value of "low" will favor speed and economical token usage, "high" will favor more complete reasoning at the cost of more tokens generated and slower responses.',
+						type: 'options',
+						options: [
+							{
+								name: 'Low',
+								value: 'low',
+								description: 'Favors speed and economical token usage',
+							},
+							{
+								name: 'Medium',
+								value: 'medium',
+								description: 'Balance between speed and reasoning accuracy',
+							},
+							{
+								name: 'High',
+								value: 'high',
+								description:
+									'Favors more complete reasoning at the cost of more tokens generated and slower responses',
+							},
+						],
+					},
+					{
+						displayName: 'Top P',
+						name: 'topP',
+						default: 1,
+						typeOptions: { maxValue: 1, minValue: 0, numberPrecision: 1 },
+						description:
+							'Controls diversity via nucleus sampling: 0.5 means half of all likelihood-weighted options are considered. We generally recommend altering this or temperature but not both.',
+						type: 'number',
+					},
+				],
+			},
+		],
+	};
+
+	async supplyData(this: ISupplyDataFunctions, itemIndex: number): Promise<SupplyData> {
+		const credentials = await this.getCredentials('truefoundryAiGatewayApi');
+
+		const modelName = this.getNodeParameter('model.value', itemIndex) as string;
+
+		const options = this.getNodeParameter('options', itemIndex, {}) as {
+			frequencyPenalty?: number;
+			maxTokens?: number;
+			presencePenalty?: number;
+			temperature?: number;
+			topP?: number;
+			timeout?: number;
+			maxRetries?: number;
+			responseFormat?: 'text' | 'json_object';
+			reasoningEffort?: 'low' | 'medium' | 'high';
+		};
+
+		const configuration: ClientOptions = {
+			baseURL: credentials.url as string,
+			fetchOptions: {
+				dispatcher: getProxyAgent(credentials.url as string),
+			},
+		};
+
+		// Add TrueFoundry metadata header with user email
+		const userEmail = this.evaluateExpression(
+			'{{ JSON.stringify({"x-n8n-user": $json.metadata.user.email}) }}',
+			itemIndex,
+		) as string;
+
+		if (userEmail && userEmail.startsWith('{')) {
+			configuration.defaultHeaders = {
+				'X-TFY-METADATA': userEmail,
+			};
+		}
+
+		// Also add any custom headers from credentials if provided
+		if (
+			credentials.header &&
+			typeof credentials.headerName === 'string' &&
+			credentials.headerName &&
+			typeof credentials.headerValue === 'string'
+		) {
+			configuration.defaultHeaders = {
+				...configuration.defaultHeaders,
+				[credentials.headerName]: credentials.headerValue,
+			};
+		}
+
+		// Extra options to send to TrueFoundry AI Gateway, that are not directly supported by LangChain
+		const modelKwargs: {
+			response_format?: object;
+			reasoning_effort?: 'low' | 'medium' | 'high';
+		} = {};
+		if (options.responseFormat) modelKwargs.response_format = { type: options.responseFormat };
+		if (options.reasoningEffort && ['low', 'medium', 'high'].includes(options.reasoningEffort))
+			modelKwargs.reasoning_effort = options.reasoningEffort;
+
+		const includedOptions = pick(options, [
+			'frequencyPenalty',
+			'maxTokens',
+			'presencePenalty',
+			'temperature',
+			'topP',
+		]);
+
+		const model = new ChatOpenAI({
+			apiKey: credentials.apiKey as string,
+			model: modelName,
+			...includedOptions,
+			timeout: options.timeout ?? 360000,
+			maxRetries: options.maxRetries ?? 2,
+			configuration,
+			callbacks: [new N8nLlmTracing(this)],
+			modelKwargs,
+			onFailedAttempt: makeN8nLlmFailedAttemptHandler(this, openAiFailedAttemptHandler),
+		});
+
+		return {
+			response: model,
+		};
+	}
+}