Initial commit of n8n MCP Server

A Model Context Protocol (MCP) server that integrates with n8n, providing tools for workflow and execution management via the n8n API.

src/tools/workflow/update.ts

@@ -0,0 +1,125 @@
+/**
+ * Update Workflow Tool
+ * 
+ * This tool updates an existing workflow in n8n.
+ */
+
+import { BaseWorkflowToolHandler } from './base-handler.js';
+import { ToolCallResult, ToolDefinition } from '../../types/index.js';
+import { N8nApiError } from '../../errors/index.js';
+
+/**
+ * Handler for the update_workflow tool
+ */
+export class UpdateWorkflowHandler extends BaseWorkflowToolHandler {
+  /**
+   * Execute the tool
+   * 
+   * @param args Tool arguments containing workflow updates
+   * @returns Updated workflow information
+   */
+  async execute(args: Record<string, any>): Promise<ToolCallResult> {
+    return this.handleExecution(async (args) => {
+      const { workflowId, name, nodes, connections, active, tags } = args;
+      
+      if (!workflowId) {
+        throw new N8nApiError('Missing required parameter: workflowId');
+      }
+      
+      // Validate nodes if provided
+      if (nodes && !Array.isArray(nodes)) {
+        throw new N8nApiError('Parameter "nodes" must be an array');
+      }
+      
+      // Validate connections if provided
+      if (connections && typeof connections !== 'object') {
+        throw new N8nApiError('Parameter "connections" must be an object');
+      }
+      
+      // Get the current workflow to update
+      const currentWorkflow = await this.apiService.getWorkflow(workflowId);
+      
+      // Prepare update object with changes
+      const workflowData: Record<string, any> = { ...currentWorkflow };
+      
+      // Update fields if provided
+      if (name !== undefined) workflowData.name = name;
+      if (nodes !== undefined) workflowData.nodes = nodes;
+      if (connections !== undefined) workflowData.connections = connections;
+      if (active !== undefined) workflowData.active = active;
+      if (tags !== undefined) workflowData.tags = tags;
+      
+      // Update the workflow
+      const updatedWorkflow = await this.apiService.updateWorkflow(workflowId, workflowData);
+      
+      // Build a summary of changes
+      const changesArray = [];
+      if (name !== undefined && name !== currentWorkflow.name) changesArray.push(`name: "${currentWorkflow.name}" → "${name}"`);
+      if (active !== undefined && active !== currentWorkflow.active) changesArray.push(`active: ${currentWorkflow.active} → ${active}`);
+      if (nodes !== undefined) changesArray.push('nodes updated');
+      if (connections !== undefined) changesArray.push('connections updated');
+      if (tags !== undefined) changesArray.push('tags updated');
+      
+      const changesSummary = changesArray.length > 0
+        ? `Changes: ${changesArray.join(', ')}`
+        : 'No changes were made';
+      
+      return this.formatSuccess(
+        {
+          id: updatedWorkflow.id,
+          name: updatedWorkflow.name,
+          active: updatedWorkflow.active
+        },
+        `Workflow updated successfully. ${changesSummary}`
+      );
+    }, args);
+  }
+}
+
+/**
+ * Get tool definition for the update_workflow tool
+ * 
+ * @returns Tool definition
+ */
+export function getUpdateWorkflowToolDefinition(): ToolDefinition {
+  return {
+    name: 'update_workflow',
+    description: 'Update an existing workflow in n8n',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        workflowId: {
+          type: 'string',
+          description: 'ID of the workflow to update',
+        },
+        name: {
+          type: 'string',
+          description: 'New name for the workflow',
+        },
+        nodes: {
+          type: 'array',
+          description: 'Updated array of node objects that define the workflow',
+          items: {
+            type: 'object',
+          },
+        },
+        connections: {
+          type: 'object',
+          description: 'Updated connection mappings between nodes',
+        },
+        active: {
+          type: 'boolean',
+          description: 'Whether the workflow should be active',
+        },
+        tags: {
+          type: 'array',
+          description: 'Updated tags to associate with the workflow',
+          items: {
+            type: 'string',
+          },
+        },
+      },
+      required: ['workflowId'],
+    },
+  };
+}