Add jsonrpc local, remote and supertest clients

packages/jsonrpc/jest.config.js

@@ -1,4 +1,9 @@
 module.exports = {
+  globals: {
+    'ts-jest': {
+      compiler: 'ttypescript'
+    }
+  },
   roots: [
     '<rootDir>/src'
   ],
@@ -13,6 +18,5 @@ module.exports = {
     'jsx'
   ],
   setupFiles: ['<rootDir>/jest.setup.js'],
-  maxConcurrency: 1,
   verbose: false
 }

packages/jsonrpc/src/client.ts

@@ -0,0 +1,2 @@
+export * from './local'
+export * from './remote'

packages/jsonrpc/src/index.ts

@@ -1 +1,2 @@
+export * from './client'
 export * from './server'

packages/jsonrpc/src/local.test.ts

@@ -0,0 +1,44 @@
+import {createLocalClient} from './local'
+import {keys} from 'ts-transformer-keys'
+
+describe('local', () => {
+
+  interface IService {
+    add(a: number, b: number): number
+    addWithContext(a: number, b: number): (context: IContext) => number
+  }
+  const IServiceKeys = keys<IService>()
+
+  interface IContext {
+    userId: 1000
+  }
+
+  class Service implements IService {
+    add(a: number, b: number) {
+      return a + b
+    }
+    addWithContext = (a: number, b: number) => (context: IContext) => {
+      return a + b + context.userId
+    }
+  }
+
+  const service = new Service()
+  const proxy = createLocalClient<IService>(service, {
+    userId: 1000,
+  })
+
+  describe('add', () => {
+    it('should add two numbers', async () => {
+      const result = await proxy.add(8, 9)
+      expect(result).toBe(8 + 9)
+    })
+  })
+
+  describe('addWithContext', () => {
+    it('should add two numbers with context', async () => {
+      const result = await proxy.addWithContext(8, 9)
+      expect(result).toBe(1000 + 8 + 9)
+    })
+  })
+
+})

packages/jsonrpc/src/local.ts

@@ -0,0 +1,21 @@
+import {Asyncified} from './types'
+
+/**
+ * Creates a local client for a specific service instance. The actual service
+ * will be invoked as if it would be remotely. This helps keep the API similar
+ * on the client- and server-side.
+ */
+export function createLocalClient<T>(service: T, context: any) {
+  const proxy = new Proxy({}, {
+    get(obj, prop) {
+      return async function makeRequest(...args: any[]) {
+        const result = (service as any)[prop](...args)
+        if (typeof result === 'function') {
+          return result(context)
+        }
+        return result
+      }
+    },
+  })
+  return proxy as Asyncified<T>
+}

packages/jsonrpc/src/remote.test.ts

@@ -0,0 +1,60 @@
+/**
+ * @jest-environment node
+ */
+import bodyParser from 'body-parser'
+import express from 'express'
+import {AddressInfo} from 'net'
+import {Server} from 'http'
+import {createRemoteClient} from './remote'
+import {jsonrpc} from './server'
+import {keys} from 'ts-transformer-keys'
+
+describe('remote', () => {
+
+  interface IService {
+    add(a: number, b: number): number
+  }
+  const IServiceKeys = keys<IService>()
+
+  class Service implements IService {
+    add(a: number, b: number) {
+      return a + b
+    }
+  }
+
+  const service = new Service()
+
+  function createApp() {
+    const a = express()
+    a.use(bodyParser.json())
+    a.use('/myService', jsonrpc(service, IServiceKeys, () => ({})))
+    return a
+  }
+
+  const app = createApp()
+
+  let server: Server
+  let baseUrl: string
+  beforeEach(async () => {
+    await new Promise(resolve => {
+      server = app.listen(0, '127.0.0.1', resolve)
+    })
+    const addr = server.address() as AddressInfo
+    baseUrl = `http://${addr.address}:${addr.port}`
+  })
+
+  afterEach(() => {
+    return new Promise(resolve => {
+      server.close(resolve)
+    })
+  })
+
+  describe('method invocation', () => {
+    it('creates a proxy for remote service', async () => {
+      const s = createRemoteClient<IService>(
+        baseUrl, '/myService', IServiceKeys)
+      const result = await s.add(3, 7)
+      expect(result).toBe(3 + 7)
+    })
+  })
+})

packages/jsonrpc/src/remote.ts

@@ -0,0 +1,40 @@
+import Axios from 'axios'
+import {Asyncified} from './types'
+
+export function createRemoteClient<T>(
+  baseUrl: string,
+  url: string,
+  methods: Array<keyof T>,
+) {
+  const axios = Axios.create({
+    baseURL: baseUrl,
+  })
+
+  let id = 0
+  const service = methods.reduce((obj, method) => {
+    obj[method] = async function makeRequest(...args: any[]) {
+      id++
+      const response = await axios({
+        method: 'post',
+        url,
+        headers: {
+          'content-type': 'application/json',
+        },
+        data: {
+          id,
+          jsonrpc: '2.0',
+          method,
+          params: args,
+        },
+      })
+      if (response.data.error) {
+        // TODO create an actual error
+        throw response.data.error
+      }
+      return response.data.result
+    }
+    return obj
+  }, {} as any)
+
+  return service as Asyncified<T>
+}

packages/jsonrpc/src/server.test.ts

@@ -1,7 +1,8 @@
-import {jsonrpc} from './server'
-import request from 'supertest'
-import express from 'express'
 import bodyParser from 'body-parser'
+import express from 'express'
+import request from 'supertest'
+import {createClient} from './supertest'
+import {jsonrpc} from './server'
 
 describe('jsonrpc', () => {
 
@@ -65,42 +66,7 @@ describe('jsonrpc', () => {
     return app
   }
 
-  type ArgumentTypes<T> = T extends (...args: infer U) => infer R ? U : never
+  const client = createClient<IService>(createApp(), '/myService')
-  type RetType<T> = T extends (...args: any[]) => infer R ? R : never
-  type UnwrapHOC<T> = T extends (...args: any[]) => infer R ? R : T
-  type RetProm<T> = T extends Promise<any> ? T : Promise<T>
-  type PromisifyReturnType<T> = (...a: ArgumentTypes<T>) =>
-    RetProm<UnwrapHOC<RetType<T>>>
-  type Asyncified<T> = {
-    [K in keyof T]: PromisifyReturnType<T[K]>
-  }
-
-  function createClient<T>(app: express.Application) {
-    let id = 0
-    const proxy = new Proxy({}, {
-      get(obj, prop) {
-        id++
-        return async function makeRequest(...args: any[]) {
-          const result = await request(app)
-          .post('/myService')
-          .send({
-            jsonrpc: '2.0',
-            id,
-            method: prop,
-            params: args,
-          })
-          const {body} = result
-          if (body.error) {
-            throw body.error
-          }
-          return body.result
-        }
-      },
-    })
-    return proxy as Asyncified<T>
-  }
-
-  const client = createClient<IService>(createApp())
 
   async function getError(promise: Promise<void>) {
     let error

packages/jsonrpc/src/supertest.ts

@@ -0,0 +1,30 @@
+import request from 'supertest'
+import {Application} from 'express'
+import {Asyncified} from './types'
+
+export function createClient<T>(
+  app: Application, path: string,
+) {
+  let id = 0
+  const proxy = new Proxy({}, {
+    get(obj, prop) {
+      id++
+      return async function makeRequest(...args: any[]) {
+        const result = await request(app)
+        .post(path)
+        .send({
+          jsonrpc: '2.0',
+          id,
+          method: prop,
+          params: args,
+        })
+        const {body} = result
+        if (body.error) {
+          throw body.error
+        }
+        return body.result
+      }
+    },
+  })
+  return proxy as Asyncified<T>
+}

packages/jsonrpc/src/types.ts

@@ -0,0 +1,10 @@
+export type ArgumentTypes<T> =
+  T extends (...args: infer U) => infer R ? U : never
+export type RetType<T> = T extends (...args: any[]) => infer R ? R : never
+export type UnwrapHOC<T> = T extends (...args: any[]) => infer R ? R : T
+export type RetProm<T> = T extends Promise<any> ? T : Promise<T>
+export type PromisifyReturnType<T> = (...a: ArgumentTypes<T>) =>
+  RetProm<UnwrapHOC<RetType<T>>>
+export type Asyncified<T> = {
+  [K in keyof T]: PromisifyReturnType<T[K]>
+}

packages/tsconfig.common.json

@@ -20,6 +20,8 @@
     "plugins": [{
       "name": "typescript-tslint-plugin",
       "suppressWhileTypeErrorsPresent": true
+    }, {
+      "transform": "ts-transformer-keys/transformer"
     }]
   }
 }