Adding tests and the hello service

.github/workflows/ci.yml

@@ -0,0 +1,28 @@
+name: Run Tests
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v2
+        with:
+          node-version: 20
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run tests
+        run: npm run test

README.md

@@ -0,0 +1,26 @@
+<p align="center">
+  <img src="./assets/logo.png" width="200" style="border-radius: 10px" />
+</p>
+
+# Differential Code Examples
+
+## The simplest example
+
+To see the simplest example for a service and the service consumer, see:
+
+1. Hello service at [src/services/hello-service.ts](./src/services/hello-service.ts)
+2. Service consumer at [src/example-1-simple.ts](./src/example-1-simple.ts)
+
+To run the example:
+
+### Start the server
+
+```bash
+npm run services:hello
+```
+
+### Start the client
+
+```bash
+npm run client:hello
+```

package.json

@@ -2,14 +2,18 @@
   "name": "minimal-example",
   "version": "1.0.0",
   "description": "",
-  "scripts": {},
+  "scripts": {
+    "services:hello": "tsx src/services/hello-service.ts",
+    "client:hello": "tsx src/example-1-simple.ts",
+    "test": "DEBUG=* node --import tsx --test src/tests/example.test.ts"
+  },
   "author": "",
   "license": "MIT",
   "dependencies": {
-    "@differentialhq/core": "^3.0.3",
+    "@differentialhq/core": "^3.0.4",
     "tsx": "^4.6.2"
   },
   "devDependencies": {
     "@types/node": "^20.10.4"
   }
-}
+}

src/example-1-simple.ts

@@ -1,8 +1,15 @@
 import { d } from "./d";
-import type { helloService } from "./services/hello-world";
+import type { helloService } from "./services/hello-service";
 import process from "process";
 
 (async function () {
+  console.log("calling hello service");
+
+  // this .call is typesafe because of the generics. and you can
+  // pass in any serializable arguments you want, and accept any
+  // serializable return value you want.
+  //
+  // this function will be served by the helloService
   const greeting = await d.call<typeof helloService, "hello">(
     "hello",
     `process ${process.pid}`

src/services/hello-service.ts

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+import process from "process";
+import { d } from "../d";
+
+export const hello = async (from: string) => {
+  console.log("hello function called", from);
+  return `Hello, ${from}! I'm running on ${process.platform} and on pid=${process.pid}.`;
+};
+
+export const helloService = d.service({
+  name: "hello",
+  functions: {
+    hello,
+  },
+});
+
+// this registers a service at api.differential.dev
+// under the api secret, and makes it available for
+// any d.call() function which uses the same api secret
+helloService.start();
+
+console.log("hello service started");
+
+process.on("beforeExit", async () => {
+  console.log("stopping hello service");
+  await helloService.stop();
+});

src/tests/example.test.ts

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+import test from "node:test";
+import { helloService } from "../services/hello-service";
+import { d } from "../d";
+import assert from "node:assert";
+
+test("example", async (t) => {
+  // start the service
+  helloService.start();
+
+  const greeting = await d.call<typeof helloService, "hello">(
+    "hello",
+    `process ${process.pid}`
+  );
+
+  assert.match(
+    greeting,
+    /Hello, process \d+! I'm running on [a-z]+ and on pid=\d+/
+  );
+
+  console.log("stopping service");
+
+  // why the fuck is this service not stopping?
+
+  // stop the service
+  await helloService.stop();
+
+  console.log("stopped service");
+});