feat(n8nApi node): add core node for consuming the n8n API (#4076)

* feat(n8n node): create n8n core node for consuming the n8n API

Co-authored-by: Michael Kret <michael.k@radency.com>

packages/nodes-base/nodes/N8n/N8n.node.ts

@@ -0,0 +1,80 @@
+import { INodeType, INodeTypeDescription } from 'n8n-workflow';
+import { credentialFields, credentialOperations } from './CredentialDescription';
+import { executionFields, executionOperations } from './ExecutionDescription';
+import { workflowFields, workflowOperations } from './WorkflowDescription';
+import { searchWorkflows } from './WorkflowLocator';
+
+/**
+ * The n8n node provides access to the n8n API.
+ *
+ * See: https://docs.n8n.io/api/api-reference/
+ */
+export class N8n implements INodeType {
+	description: INodeTypeDescription = {
+		displayName: 'n8n',
+		name: 'n8n',
+		icon: 'file:n8n.svg',
+		group: ['transform'],
+		version: 1,
+		subtitle: '={{$parameter["operation"] + ": " + $parameter["resource"]}}',
+		description: 'Consume n8n API',
+		defaults: {
+			name: 'n8n',
+		},
+		inputs: ['main'],
+		outputs: ['main'],
+		credentials: [
+			{
+				name: 'n8nApi',
+				required: true,
+			},
+		],
+		requestDefaults: {
+			returnFullResponse: true,
+			baseURL: '={{ $credentials.baseUrl.replace(new RegExp("/$"), "") }}',
+			headers: {
+				Accept: 'application/json',
+				'Content-Type': 'application/json',
+			},
+		},
+		properties: [
+			{
+				displayName: 'Resource',
+				name: 'resource',
+				type: 'options',
+				noDataExpression: true,
+				options: [
+					{
+						name: 'Credential',
+						value: 'credential',
+					},
+					{
+						name: 'Execution',
+						value: 'execution',
+					},
+					{
+						name: 'Workflow',
+						value: 'workflow',
+					},
+				],
+				default: 'workflow',
+			},
+
+			...credentialOperations,
+			...credentialFields,
+
+			...executionOperations,
+			...executionFields,
+
+			...workflowOperations,
+			...workflowFields,
+		],
+	};
+
+	methods = {
+		listSearch: {
+			// Provide workflows search capability for the workflow resourceLocator
+			searchWorkflows,
+		},
+	};
+}