MCPX MCP Gateway

import { parse } from "yaml"; import { getTestHarness, stdioTargetServers } from "./utils.js"; const MCPX_BASE_URL = "http://localhost:9000"; async function patchAppConfig(config: unknown): Promise<void> { await fetch(`${MCPX_BASE_URL}/app-config`, { method: "PATCH", headers: { "Content-Type": "application/json" }, body: JSON.stringify(config), }); } describe("Target Server Activation", () => { const harness = getTestHarness({ targetServers: [] }); let initialConfig: { yaml: string; version: number; lastModified: string }; beforeAll(async () => { await harness.initialize("SSE"); const response = await fetch(`${MCPX_BASE_URL}/app-config`); initialConfig = await response.json(); }); beforeEach(async () => { const config = parse(initialConfig.yaml); await patchAppConfig({ ...config, targetServerAttributes: {}, }); }); afterAll(async () => { const config = parse(initialConfig.yaml); await patchAppConfig(config); await harness.shutdown(); }); it("activates a target server", async () => { const serverName = "test-server"; const activateResponse = await fetch( `${MCPX_BASE_URL}/target-server/${serverName}/activate`, { method: "PUT" }, ); expect(activateResponse.status).toBe(200); const attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); expect(attributesResponse.status).toBe(200); const { targetServerAttributes } = await attributesResponse.json(); expect(targetServerAttributes[serverName]).toEqual({ inactive: false }); }); it("deactivates a target server", async () => { const serverName = "test-server-2"; const deactivateResponse = await fetch( `${MCPX_BASE_URL}/target-server/${serverName}/deactivate`, { method: "PUT" }, ); expect(deactivateResponse.status).toBe(200); const attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); expect(attributesResponse.status).toBe(200); const { targetServerAttributes } = await attributesResponse.json(); expect(targetServerAttributes[serverName]).toEqual({ inactive: true }); }); it("toggles activation state", async () => { const serverName = "toggle-server"; await fetch(`${MCPX_BASE_URL}/target-server/${serverName}/activate`, { method: "PUT", }); let attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); let { targetServerAttributes } = await attributesResponse.json(); expect(targetServerAttributes[serverName]).toEqual({ inactive: false }); await fetch(`${MCPX_BASE_URL}/target-server/${serverName}/deactivate`, { method: "PUT", }); attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); ({ targetServerAttributes } = await attributesResponse.json()); expect(targetServerAttributes[serverName]).toEqual({ inactive: true }); await fetch(`${MCPX_BASE_URL}/target-server/${serverName}/activate`, { method: "PUT", }); attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); ({ targetServerAttributes } = await attributesResponse.json()); expect(targetServerAttributes[serverName]).toEqual({ inactive: false }); }); it("normalizes server names (trim and lowercase)", async () => { const serverName = " MixedCase-SERVER "; const normalizedName = "mixedcase-server"; await fetch(`${MCPX_BASE_URL}/target-server/${serverName}/activate`, { method: "PUT", }); const attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); const { targetServerAttributes } = await attributesResponse.json(); expect(targetServerAttributes[normalizedName]).toEqual({ inactive: false, }); expect(targetServerAttributes[serverName]).toBeUndefined(); }); it("preserves existing attributes when toggling state", async () => { const serverName = "server-with-attrs"; await fetch(`${MCPX_BASE_URL}/target-server/${serverName}/activate`, { method: "PUT", }); let attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); let { targetServerAttributes } = await attributesResponse.json(); const initialAttributes = targetServerAttributes[serverName]; await fetch(`${MCPX_BASE_URL}/target-server/${serverName}/deactivate`, { method: "PUT", }); attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); ({ targetServerAttributes } = await attributesResponse.json()); expect(targetServerAttributes[serverName]).toEqual({ ...initialAttributes, inactive: true, }); }); it("returns 400 when server name is missing", async () => { const activateResponse = await fetch( `${MCPX_BASE_URL}/target-server//activate`, { method: "PUT" }, ); expect(activateResponse.status).toBe(404); const deactivateResponse = await fetch( `${MCPX_BASE_URL}/target-server//deactivate`, { method: "PUT" }, ); expect(deactivateResponse.status).toBe(404); }); it("retrieves empty attributes when no servers configured", async () => { const attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); expect(attributesResponse.status).toBe(200); const { targetServerAttributes } = await attributesResponse.json(); expect(Object.keys(targetServerAttributes).length).toBe(0); }); it("persists attributes across multiple operations", async () => { const server1 = "persist-server-1"; const server2 = "persist-server-2"; await fetch(`${MCPX_BASE_URL}/target-server/${server1}/activate`, { method: "PUT", }); await fetch(`${MCPX_BASE_URL}/target-server/${server2}/deactivate`, { method: "PUT", }); const attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); const { targetServerAttributes } = await attributesResponse.json(); expect(targetServerAttributes[server1]).toEqual({ inactive: false }); expect(targetServerAttributes[server2]).toEqual({ inactive: true }); }); describe("idempotency", () => { it("handles activating twice in a row", async () => { const serverName = "double-activate"; const firstActivate = await fetch( `${MCPX_BASE_URL}/target-server/${serverName}/activate`, { method: "PUT" }, ); expect(firstActivate.status).toBe(200); const secondActivate = await fetch( `${MCPX_BASE_URL}/target-server/${serverName}/activate`, { method: "PUT" }, ); expect(secondActivate.status).toBe(200); const attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); const { targetServerAttributes } = await attributesResponse.json(); expect(targetServerAttributes[serverName]).toEqual({ inactive: false }); }); it("handles deactivating twice in a row", async () => { const serverName = "double-deactivate"; const firstDeactivate = await fetch( `${MCPX_BASE_URL}/target-server/${serverName}/deactivate`, { method: "PUT" }, ); expect(firstDeactivate.status).toBe(200); const secondDeactivate = await fetch( `${MCPX_BASE_URL}/target-server/${serverName}/deactivate`, { method: "PUT" }, ); expect(secondDeactivate.status).toBe(200); const attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); const { targetServerAttributes } = await attributesResponse.json(); expect(targetServerAttributes[serverName]).toEqual({ inactive: true }); }); }); describe("tool filtering behavior", () => { beforeAll(async () => { await Promise.all( stdioTargetServers.map((server) => fetch(`${MCPX_BASE_URL}/target-server`, { method: "POST", headers: { "Content-Type": "application/json" }, body: JSON.stringify(server), }), ), ); }); afterAll(async () => { await Promise.all( stdioTargetServers.map((server) => fetch(`${MCPX_BASE_URL}/target-server/${server.name}`, { method: "DELETE", }), ), ); }); it("excludes tools from inactive servers in list_tools", async () => { const initialTools = await harness.client.listTools(); const echoTools = initialTools.tools.filter((t) => t.name.startsWith("echo-service__"), ); expect(echoTools.length).toBeGreaterThan(0); await fetch(`${MCPX_BASE_URL}/target-server/echo-service/deactivate`, { method: "PUT", }); const toolsAfterDeactivate = await harness.client.listTools(); const echoToolsAfterDeactivate = toolsAfterDeactivate.tools.filter((t) => t.name.startsWith("echo-service__"), ); expect(echoToolsAfterDeactivate).toHaveLength(0); await fetch(`${MCPX_BASE_URL}/target-server/echo-service/activate`, { method: "PUT", }); const toolsAfterReactivate = await harness.client.listTools(); const echoToolsAfterReactivate = toolsAfterReactivate.tools.filter((t) => t.name.startsWith("echo-service__"), ); expect(echoToolsAfterReactivate.length).toBe(echoTools.length); }); it("blocks tool calls to inactive servers", async () => { const result = await harness.client.callTool({ name: "echo-service__echo", arguments: { message: "test" }, }); expect(result.content).toBeDefined(); await fetch(`${MCPX_BASE_URL}/target-server/echo-service/deactivate`, { method: "PUT", }); await expect( harness.client.callTool({ name: "echo-service__echo", arguments: { message: "test" }, }), ).rejects.toThrow(/inactive/i); await fetch(`${MCPX_BASE_URL}/target-server/echo-service/activate`, { method: "PUT", }); const resultAfterReactivate = await harness.client.callTool({ name: "echo-service__echo", arguments: { message: "test" }, }); expect(resultAfterReactivate.content).toBeDefined(); }); it("does not affect other servers when one is deactivated", async () => { await fetch(`${MCPX_BASE_URL}/target-server/echo-service/deactivate`, { method: "PUT", }); const result = await harness.client.callTool({ name: "calculator-service__add", arguments: { a: 2, b: 3 }, }); expect(result.content).toBeDefined(); const tools = await harness.client.listTools(); const calculatorTools = tools.tools.filter((t) => t.name.startsWith("calculator-service__"), ); expect(calculatorTools.length).toBeGreaterThan(0); }); }); describe("cleanup on removal", () => { it("removes deleted server attributes and preserves others", async () => { const server1 = "removal-test-1"; const server2 = "removal-test-2"; const echoServer = stdioTargetServers[0]; const calculatorServer = stdioTargetServers[1]; const targetServer1 = { ...echoServer, name: server1 }; await fetch(`${MCPX_BASE_URL}/target-server`, { method: "POST", headers: { "Content-Type": "application/json" }, body: JSON.stringify(targetServer1), }); const targetServer2 = { ...calculatorServer, name: server2 }; await fetch(`${MCPX_BASE_URL}/target-server`, { method: "POST", headers: { "Content-Type": "application/json" }, body: JSON.stringify(targetServer2), }); await fetch(`${MCPX_BASE_URL}/target-server/${server1}/deactivate`, { method: "PUT", }); await fetch(`${MCPX_BASE_URL}/target-server/${server2}/deactivate`, { method: "PUT", }); let attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); let { targetServerAttributes } = await attributesResponse.json(); expect(targetServerAttributes[server1]).toEqual({ inactive: true }); expect(targetServerAttributes[server2]).toEqual({ inactive: true }); const deleteResponse = await fetch( `${MCPX_BASE_URL}/target-server/${server1}`, { method: "DELETE" }, ); expect(deleteResponse.status).toBe(200); attributesResponse = await fetch( `${MCPX_BASE_URL}/target-servers/attributes`, ); ({ targetServerAttributes } = await attributesResponse.json()); expect(targetServerAttributes[server1]).toBeUndefined(); expect(targetServerAttributes[server2]).toEqual({ inactive: true }); await fetch(`${MCPX_BASE_URL}/target-server/${server2}`, { method: "DELETE", }); }); }); });