feat: async API (#3608)

migration-v4.md

@@ -491,6 +491,106 @@ module.exports = {
 - The `sockWrite` public method was renamed to `sendMessage`.
 - The `profile` option was removed in favor [`ProfilingPlugin`](https://webpack.js.org/plugins/profiling-plugin/).
 
+### Deprecations
+
+- `constructor` arguments were changed, the first argument is dev server options, the second is compiler
+
+  v3:
+
+  ```js
+  const devServerOptions = { host: "127.0.0.1", port: 8080 };
+  const devServer = new Server(compiler, devServerOptions);
+  ```
+
+  v4:
+
+  ```js
+  const devServerOptions = { host: "127.0.0.1", port: 8080 };
+  const devServer = new Server(devServerOptions, compiler);
+  ```
+
+- `listen` method is deprecated in favor async `start` or `startCallback` methods
+
+  v3:
+
+  ```js
+  const devServerOptions = { host: "127.0.0.1", port: 8080 };
+  const devServer = new Server(compiler, devServerOptions);
+
+  devServer.listen(devServerOptions.host, devServerOptions.port, () => {
+    console.log("Running");
+  });
+  ```
+
+  v4:
+
+  ```js
+  const devServerOptions = { host: "127.0.0.1", port: 8080 };
+  const devServer = new Server(compiler, devServerOptions);
+
+  (async () => {
+    await devServer.start();
+
+    console.log("Running");
+  })();
+  ```
+
+  ```js
+  const devServerOptions = { host: "127.0.0.1", port: 8080 };
+  const devServer = new Server(compiler, devServerOptions);
+
+  devServer.startCallback(() => {
+    console.log("Running");
+  });
+  ```
+
+- `close` method is deprecated in favor async `stop` or `stopCallback` methods
+
+  v3:
+
+  ```js
+  const devServerOptions = { host: "127.0.0.1", port: 8080 };
+  const devServer = new Server(compiler, devServerOptions);
+
+  devServer.listen(devServerOptions.host, devServerOptions.port, () => {
+    console.log("Running");
+
+    devServer.close(() => {
+      console.log("Closed");
+    });
+  });
+  ```
+
+  v4:
+
+  ```js
+  const devServerOptions = { host: "127.0.0.1", port: 8080 };
+  const devServer = new Server(compiler, devServerOptions);
+
+  (async () => {
+    await devServer.start();
+
+    console.log("Running");
+
+    await devServer.stop();
+
+    console.log("Closed");
+  })();
+  ```
+
+  ```js
+  const devServerOptions = { host: "127.0.0.1", port: 8080 };
+  const devServer = new Server(compiler, devServerOptions);
+
+  devServer.startCallback(() => {
+    console.log("Running");
+
+    devServer.stopCallback(() => {
+      console.log("Closed");
+    });
+  });
+  ```
+
 ### Features
 
 - Added the `setupExitSignals` option, it takes a boolean and if `true` (default on CLI), the server will close and exit the process on `SIGINT` and `SIGTERM`.
@@ -503,6 +603,8 @@ module.exports = {
 - Overlay can be closed in browser.
 - The `allowedHosts` option can be `auto` or custom string with your domain (i.e. default value).
 - The `static` option can be disabled using `static: false`.
+- Added async `start` and `stop` methods to API
+- Added `startCallback` and `stopCallback` methods to API
 
 ### Bug Fixes
 

test/client/bundle.test.js

@@ -21,27 +21,13 @@ describe("bundle", () => {
 
       server = new Server({ port }, compiler);
 
-      await new Promise((resolve, reject) => {
-        server.listen(port, "127.0.0.1", (error) => {
-          if (error) {
-            reject(error);
-
-            return;
-          }
-
-          resolve();
-        });
-      });
+      await server.start();
 
       req = request(server.app);
     });
 
     afterAll(async () => {
-      await new Promise((resolve) => {
-        server.close(() => {
-          resolve();
-        });
-      });
+      await server.stop();
     });
 
     it("should get full user bundle and parse with ES5", async () => {

test/e2e/__snapshots__/api.test.js.snap.webpack4

@@ -0,0 +1,34 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`API should work with async API: console messages 1`] = `
+Array [
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+  "[webpack-dev-server] Hot Module Replacement enabled.",
+  "[webpack-dev-server] Live Reloading enabled.",
+]
+`;
+
+exports[`API should work with async API: page errors 1`] = `Array []`;
+
+exports[`API should work with callback API: console messages 1`] = `
+Array [
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+  "[webpack-dev-server] Hot Module Replacement enabled.",
+  "[webpack-dev-server] Live Reloading enabled.",
+]
+`;
+
+exports[`API should work with callback API: page errors 1`] = `Array []`;
+
+exports[`API should work with deprecated API: console messages 1`] = `
+Array [
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+  "[webpack-dev-server] Hot Module Replacement enabled.",
+  "[webpack-dev-server] Live Reloading enabled.",
+]
+`;
+
+exports[`API should work with deprecated API: page errors 1`] = `Array []`;

test/e2e/__snapshots__/api.test.js.snap.webpack5

@@ -0,0 +1,34 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`API should work with async API: console messages 1`] = `
+Array [
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+  "[webpack-dev-server] Hot Module Replacement enabled.",
+  "[webpack-dev-server] Live Reloading enabled.",
+]
+`;
+
+exports[`API should work with async API: page errors 1`] = `Array []`;
+
+exports[`API should work with callback API: console messages 1`] = `
+Array [
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+  "[webpack-dev-server] Hot Module Replacement enabled.",
+  "[webpack-dev-server] Live Reloading enabled.",
+]
+`;
+
+exports[`API should work with callback API: page errors 1`] = `Array []`;
+
+exports[`API should work with deprecated API: console messages 1`] = `
+Array [
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+  "[webpack-dev-server] Hot Module Replacement enabled.",
+  "[webpack-dev-server] Live Reloading enabled.",
+]
+`;
+
+exports[`API should work with deprecated API: page errors 1`] = `Array []`;