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/resources/dynamic/workflow.ts

@@ -0,0 +1,88 @@
+/**
+ * Dynamic Workflow Resource Handler
+ * 
+ * This module provides the MCP resource implementation for retrieving
+ * detailed workflow information by ID.
+ */
+
+import { N8nApiService } from '../../api/n8n-client.js';
+import { formatWorkflowDetails, formatResourceUri } from '../../utils/resource-formatter.js';
+import { McpError, ErrorCode } from '../../errors/index.js';
+
+/**
+ * Get workflow resource data by ID
+ * 
+ * @param apiService n8n API service
+ * @param workflowId Workflow ID
+ * @returns Formatted workflow resource data
+ */
+export async function getWorkflowResource(apiService: N8nApiService, workflowId: string): Promise<string> {
+  try {
+    // Get the specific workflow from the API
+    const workflow = await apiService.getWorkflow(workflowId);
+    
+    // Format the workflow for resource consumption
+    const formattedWorkflow = formatWorkflowDetails(workflow);
+    
+    // Add metadata about the resource
+    const result = {
+      resourceType: 'workflow',
+      id: workflowId,
+      ...formattedWorkflow,
+      _links: {
+        self: formatResourceUri('workflow', workflowId),
+        // Include links to related resources
+        executions: `n8n://executions?workflowId=${workflowId}`,
+      },
+      lastUpdated: new Date().toISOString(),
+    };
+    
+    return JSON.stringify(result, null, 2);
+  } catch (error) {
+    console.error(`Error fetching workflow resource (ID: ${workflowId}):`, error);
+    
+    // Handle not found errors specifically
+    if (error instanceof McpError && error.code === ErrorCode.NotFoundError) {
+      throw error;
+    }
+    
+    throw new McpError(
+      ErrorCode.InternalError, 
+      `Failed to retrieve workflow (ID: ${workflowId}): ${error instanceof Error ? error.message : 'Unknown error'}`
+    );
+  }
+}
+
+/**
+ * Get workflow resource template URI
+ * 
+ * @returns Formatted resource template URI
+ */
+export function getWorkflowResourceTemplateUri(): string {
+  return 'n8n://workflows/{id}';
+}
+
+/**
+ * Get workflow resource template metadata
+ * 
+ * @returns Resource template metadata object
+ */
+export function getWorkflowResourceTemplateMetadata(): Record<string, any> {
+  return {
+    uriTemplate: getWorkflowResourceTemplateUri(),
+    name: 'n8n Workflow Details',
+    mimeType: 'application/json',
+    description: 'Detailed information about a specific n8n workflow including all nodes, connections, and settings',
+  };
+}
+
+/**
+ * Extract workflow ID from resource URI
+ * 
+ * @param uri Resource URI
+ * @returns Workflow ID or null if URI format is invalid
+ */
+export function extractWorkflowIdFromUri(uri: string): string | null {
+  const match = uri.match(/^n8n:\/\/workflows\/([^/]+)$/);
+  return match ? match[1] : null;
+}