feat: wip gateway mcp work

.vscode/launch.json

@@ -22,7 +22,7 @@
        * Useful to see console.logs
        */
       "console": "integratedTerminal",
-      "internalConsoleOptions": "openOnFirstSessionStart",
+      "internalConsoleOptions": "neverOpen",
 
       // Files to exclude from debugger (e.g. call stack)
       "skipFiles": [
@@ -33,5 +33,44 @@
         // "${workspaceFolder}/node_modules/**"
       ]
     }
+    // Wrangler's vscode support seems to be extremely buggy. It sometimes works
+    // 1/10th of the time, but nothing I tried could improve that consistency.
+    // Will use browser debugger instead for now.
+    // {
+    //   "name": "gateway",
+    //   "type": "node",
+    //   "request": "attach",
+    //   "port": 9229,
+    //   "cwd": "${workspaceFolder}/apps/gateway",
+    //   // "cwd": "${workspaceFolder}",
+    //   // "cwd": "/",
+    //   "attachExistingChildren": false,
+    //   "autoAttachChildProcesses": false,
+    //   "sourceMaps": true,
+    //   "outFiles": ["${workspaceFolder}/apps/gateway/.wrangler/tmp/**/*"],
+    //   "resolveSourceMapLocations": null,
+    //   // "resolveSourceMapLocations": ["**", "!**/node_modules/**"],
+    //   "skipFiles": ["<node_internals>/**"],
+    //   "internalConsoleOptions": "neverOpen",
+    //   "restart": true
+    // },
+    // {
+    //   "name": "Wrangler",
+    //   "type": "node",
+    //   "request": "attach",
+    //   "port": 9229,
+    //   "cwd": "/",
+    //   "resolveSourceMapLocations": null,
+    //   "attachExistingChildren": false,
+    //   "autoAttachChildProcesses": false,
+    //   "sourceMaps": true // works with or without this line (supposedly)
+    // }
   ]
+  // "compounds": [
+  //   {
+  //     "name": "Debug Workers",
+  //     "configurations": ["gateway"],
+  //     "stopAll": true
+  //   }
+  // ]
 }

apps/e2e/package.json

@@ -15,7 +15,9 @@
     "test": "run-s test:*",
     "test:lint": "eslint .",
     "test:typecheck": "tsc --noEmit",
-    "test-e2e": "vitest run"
+    "test-e2e": "vitest run",
+    "test-http-e2e": "vitest run src/http-e2e.test.ts",
+    "test-mcp-e2e": "vitest run src/mcp-e2e.test.ts"
   },
   "dependencies": {
     "ky": "catalog:",
@@ -26,6 +28,7 @@
     "@agentic/platform-api-client": "workspace:*",
     "@agentic/platform-core": "workspace:*",
     "@agentic/platform-fixtures": "workspace:*",
-    "fast-content-type-parse": "catalog:"
+    "fast-content-type-parse": "catalog:",
+    "@modelcontextprotocol/sdk": "catalog:"
   }
 }

apps/e2e/src/http-e2e.test.ts

@@ -3,7 +3,7 @@ import defaultKy from 'ky'
 import { describe, expect, test } from 'vitest'
 
 import { env } from './env'
-import { fixtureSuites } from './fixtures'
+import { fixtureSuites } from './http-fixtures'
 
 const ky = defaultKy.extend({
   prefixUrl: env.AGENTIC_GATEWAY_BASE_URL,
@@ -28,7 +28,8 @@ for (const [i, fixtureSuite] of fixtureSuites.entries()) {
         status = 200,
         contentType: expectedContentType = 'application/json',
         headers: expectedHeaders,
-        body: expectedBody
+        body: expectedBody,
+        validate
       } = fixture.response ?? {}
       const snapshot =
         fixture.response?.snapshot ??
@@ -85,6 +86,10 @@ for (const [i, fixtureSuite] of fixtureSuites.entries()) {
             expect(body).toEqual(expectedBody)
           }
 
+          if (validate) {
+            await Promise.resolve(validate(body))
+          }
+
           if (snapshot) {
             expect(body).toMatchSnapshot()
           }

apps/e2e/src/http-fixtures.ts

@@ -26,7 +26,7 @@ export type E2ETestFixture = {
     contentType?: string
     headers?: Record<string, string>
     body?: any
-    validate?: (body: any) => void
+    validate?: (body: any) => void | Promise<void>
     /** @default true */
     snapshot?: boolean
   }

apps/e2e/src/mcp-e2e.test.ts

@@ -0,0 +1,89 @@
+import { Client as McpClient } from '@modelcontextprotocol/sdk/client/index.js'
+import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/streamableHttp.js'
+import { afterAll, beforeAll, describe, expect, test } from 'vitest'
+
+import { env } from './env'
+import { fixtureSuites } from './mcp-fixtures'
+
+for (const [i, fixtureSuite] of fixtureSuites.entries()) {
+  const { title, fixtures, compareResponseBodies = false } = fixtureSuite
+
+  const describeFn = fixtureSuite.only ? describe.only : describe
+  describeFn(title, () => {
+    let fixtureResult: any | undefined
+
+    let client: McpClient
+    beforeAll(async () => {
+      client = new McpClient({
+        name: fixtureSuite.path,
+        version: '0.0.0'
+      })
+
+      const transport = new StreamableHTTPClientTransport(
+        new URL(fixtureSuite.path, env.AGENTIC_GATEWAY_BASE_URL)
+      )
+      await client.connect(transport)
+    }, 120_000)
+
+    afterAll(async () => {
+      await client.close()
+    })
+
+    for (const [j, fixture] of fixtures.entries()) {
+      const { isError, body: expectedBody, validate } = fixture.response ?? {}
+      const snapshot =
+        fixture.response?.snapshot ?? fixtureSuite.snapshot ?? !isError
+      const debugFixture = !!(fixture.debug ?? fixtureSuite.debug)
+      const fixtureName = `${i}.${j}: ${fixtureSuite.path} ${fixture.request.name}`
+
+      let testFn = fixture.only ? test.only : test
+      if (fixtureSuite.sequential) {
+        testFn = testFn.sequential
+      }
+
+      testFn(
+        fixtureName,
+        {
+          timeout: fixture.timeout ?? 60_000
+        },
+        // eslint-disable-next-line no-loop-func
+        async () => {
+          const { tools } = await client.listTools()
+          console.log('tools', tools)
+          expect(tools.map((t) => t.name)).toContain(fixture.request.name)
+
+          const result = await client.callTool(fixture.request)
+          if (isError) {
+            expect(result.isError).toBeTruthy()
+          } else {
+            expect(result.isError).toBeFalsy()
+          }
+
+          if (expectedBody) {
+            expect(result).toEqual(expectedBody)
+          }
+
+          if (snapshot) {
+            expect(result).toMatchSnapshot()
+          }
+
+          if (validate) {
+            await Promise.resolve(validate(result))
+          }
+
+          if (compareResponseBodies && !isError) {
+            if (!fixtureResult) {
+              fixtureResult = result
+            } else {
+              expect(result).toEqual(fixtureResult)
+            }
+          }
+
+          if (debugFixture) {
+            console.log(fixtureName, '=>', fixtureResult)
+          }
+        }
+      )
+    }
+  })
+}

apps/e2e/src/mcp-fixtures.ts

@@ -0,0 +1,110 @@
+export type MCPE2ETestFixture = {
+  /** @default 60_000 milliseconds */
+  timeout?: number
+
+  /** @default false */
+  only?: boolean
+
+  /** @default false */
+  debug?: boolean
+
+  request: {
+    name: string
+    args: Record<string, unknown>
+  }
+
+  response?: {
+    isError?: boolean
+    body?: any
+    validate?: (result: any) => void | Promise<void>
+    /** @default true */
+    snapshot?: boolean
+  }
+}
+
+export type MCPE2ETestFixtureSuite = {
+  title: string
+  path: string
+  fixtures: MCPE2ETestFixture[]
+
+  /** @default false */
+  only?: boolean
+
+  /** @default false */
+  sequential?: boolean
+
+  /** @default false */
+  compareResponseBodies?: boolean
+
+  /** @default false */
+  debug?: boolean
+
+  /** @default undefined */
+  snapshot?: boolean
+}
+
+const now = Date.now()
+
+export const fixtureSuites: MCPE2ETestFixtureSuite[] = [
+  {
+    title: 'Basic MCP => OpenAPI get_post success',
+    path: '@dev/test-basic-openapi/mcp',
+    fixtures: [
+      {
+        request: {
+          name: 'get_post',
+          args: {
+            postId: 1
+          }
+        }
+      }
+    ]
+  }
+  // {
+  //   title: 'Basic MCP => MCP "echo" tool call success',
+  //   path: '@dev/test-basic-mcp/mcp',
+  //   snapshot: false,
+  //   fixtures: [
+  //     {
+  //       request: {
+  //         name: 'echo',
+  //         args: {
+  //           nala: 'kitten',
+  //           num: 123,
+  //           now
+  //         }
+  //       },
+  //       response: {
+  //         body: [
+  //           {
+  //             type: 'text',
+  //             text: JSON.stringify({ nala: 'kitten', num: 123, now })
+  //           }
+  //         ]
+  //       }
+  //     },
+  //     {
+  //       request: {
+  //         name: 'echo',
+  //         args: {
+  //           nala: 'kitten',
+  //           num: 123,
+  //           now: `${now}`
+  //         }
+  //       },
+  //       response: {
+  //         body: [
+  //           {
+  //             type: 'text',
+  //             text: JSON.stringify({
+  //               nala: 'kitten',
+  //               num: '123',
+  //               now: `${now}`
+  //             })
+  //           }
+  //         ]
+  //       }
+  //     }
+  //   ]
+  // }
+]

apps/gateway/package.json

@@ -20,7 +20,6 @@
   "scripts": {
     "deploy": "wrangler deploy",
     "dev": "wrangler dev",
-    "start": "wrangler dev",
     "cf-clear-cache": "del .wrangler",
     "clean": "del dist",
     "test": "run-s test:*",

apps/gateway/src/lib/resolve-mcp-edge-request.ts

@@ -1,6 +1,6 @@
 import type { AdminDeployment, PricingPlan } from '@agentic/platform-types'
 import { assert } from '@agentic/platform-core'
-import { parseDeploymentIdentifier } from '@agentic/platform-validators'
+import { parseToolIdentifier } from '@agentic/platform-validators'
 
 import type { AdminConsumer, GatewayHonoContext } from './types'
 import { getAdminConsumer } from './get-admin-consumer'
@@ -16,7 +16,7 @@ export async function resolveMcpEdgeRequest(ctx: GatewayHonoContext): Promise<{
   const requestedDeploymentIdentifier = pathname
     .replace(/^\//, '')
     .replace(/\/$/, '')
-  const { deploymentIdentifier } = parseDeploymentIdentifier(
+  const { deploymentIdentifier } = parseToolIdentifier(
     requestedDeploymentIdentifier
   )
 

apps/gateway/src/mcp.ts

@@ -231,6 +231,9 @@ export async function handleMcpRequest(ctx: GatewayHonoContext) {
 
   // eslint-disable-next-line unicorn/prefer-add-event-listener
   transport.onmessage = async (message) => {
+    // eslint-disable-next-line no-console
+    console.log('onmessage', message)
+
     // validate that the message is a valid JSONRPC message
     const result = JSONRPCMessageSchema.safeParse(message)
     if (!result.success) {
@@ -251,6 +254,7 @@ export async function handleMcpRequest(ctx: GatewayHonoContext) {
     // If we have received all the responses, close the connection
     if (!requestIds.size) {
       ctx.executionCtx.waitUntil(transport.close())
+      await writer.close()
     }
   }
 

apps/gateway/tsconfig.json

@@ -1,7 +1,7 @@
 {
   "extends": "@fisch0920/config/tsconfig-node",
   "compilerOptions": {
-    "types": ["@cloudflare/workers-types/experimental"]
+    "types": ["@cloudflare/workers-types"]
   },
   "include": ["src", "*.config.ts"],
   "exclude": ["node_modules", "dist"]

apps/gateway/wrangler.jsonc

@@ -43,6 +43,8 @@
    */
   "placement": { "mode": "smart" },
 
+  "upload_source_maps": true,
+
   /**
    * Bindings
    * Bindings allow your Worker to interact with resources on the Cloudflare Developer Platform, including

packages/hono/src/error-handler.ts

@@ -68,7 +68,7 @@ export function errorHandler(
 }
 
 /** Error codes defined by the JSON-RPC specification. */
-export declare enum JsonRpcErrorCodes {
+export enum JsonRpcErrorCodes {
   ConnectionClosed = -32_000,
   RequestTimeout = -32_001,
   ParseError = -32_700,

pnpm-lock.yaml

@@ -397,6 +397,9 @@ importers:
       '@agentic/platform-fixtures':
         specifier: workspace:*
         version: link:../../packages/fixtures
+      '@modelcontextprotocol/sdk':
+        specifier: 'catalog:'
+        version: 1.12.1
       fast-content-type-parse:
         specifier: 'catalog:'
         version: 3.0.0