import { Tool } from '@langchain/core/tools' import { ICommonObject, INode, INodeData, INodeOptionsValue, INodeParams } from '../../../../src/Interface' import { getCredentialData, getCredentialParam, getNodeModulesPackagePath } from '../../../../src/utils' import { MCPToolkit } from '../core' class PostgreSQL_MCP implements INode { label: string name: string version: number description: string type: string icon: string category: string baseClasses: string[] credential: INodeParams documentation: string inputs: INodeParams[] constructor() { this.label = 'PostgreSQL MCP' this.name = 'postgreSQLMCP' this.version = 1.0 this.type = 'PostgreSQL MCP Tool' this.icon = 'postgres.svg' this.category = 'Tools (MCP)' this.description = 'MCP server that provides read-only access to PostgreSQL databases' this.documentation = 'https://github.com/modelcontextprotocol/servers/tree/main/src/postgres' this.credential = { label: 'Connect Credential', name: 'credential', type: 'credential', credentialNames: ['PostgresUrl'] } this.inputs = [ { label: 'Available Actions', name: 'mcpActions', type: 'asyncMultiOptions', loadMethod: 'listActions', refresh: true } ] this.baseClasses = ['Tool'] } //@ts-ignore loadMethods = { listActions: async (nodeData: INodeData, options: ICommonObject): Promise => { try { const toolset = await this.getTools(nodeData, options) toolset.sort((a: any, b: any) => a.name.localeCompare(b.name)) return toolset.map(({ name, ...rest }) => ({ label: name.toUpperCase(), name: name, description: rest.description || name })) } catch (error) { console.error('Error listing actions:', error) return [ { label: 'No Available Actions', name: 'error', description: 'No available actions, please check your postgres url and refresh' } ] } } } async init(nodeData: INodeData, _: string, options: ICommonObject): Promise { const tools = await this.getTools(nodeData, options) const _mcpActions = nodeData.inputs?.mcpActions let mcpActions = [] if (_mcpActions) { try { mcpActions = typeof _mcpActions === 'string' ? JSON.parse(_mcpActions) : _mcpActions } catch (error) { console.error('Error parsing mcp actions:', error) } } return tools.filter((tool: any) => mcpActions.includes(tool.name)) } async getTools(nodeData: INodeData, options: ICommonObject): Promise { const credentialData = await getCredentialData(nodeData.credential ?? '', options) const postgresUrl = getCredentialParam('postgresUrl', credentialData, nodeData) if (!postgresUrl) { throw new Error('No postgres url provided') } const packagePath = getNodeModulesPackagePath('@modelcontextprotocol/server-postgres/dist/index.js') const serverParams = { command: 'node', args: [packagePath, postgresUrl] } const toolkit = new MCPToolkit(serverParams, 'stdio') await toolkit.initialize() const tools = toolkit.tools ?? [] return tools as Tool[] } } module.exports = { nodeClass: PostgreSQL_MCP }