feat: supports retrieving the port from the configuration file (#251)

Adjust the order in which ports are obtained：option `--port` > [_egg.js_
configuration](https://www.eggjs.org/basics/config) `config/config.*.js`
> `process.env.EGG_BIN_DEFAULT_PORT` > 7001 > other available ports.


![image](https://github.com/eggjs/egg-bin/assets/35088591/ab8ffafd-c3f3-414b-a46e-a0a8fb897a17)

closes #250

---------

Co-authored-by: tiga <tigazhuang@futunn.com>

README.md

@@ -74,7 +74,7 @@ egg-bin dev
 #### dev options
 
 - `--framework` egg web framework root path.
-- `--port` server port, default to `7001`.
+- `--port` server port. If not specified, the port is obtained in the following order: [_egg.js_ configuration](https://www.eggjs.org/basics/config) `config/config.*.js` > `process.env.EGG_BIN_DEFAULT_PORT` > 7001 > other available ports.
 - `--workers` worker process number, default to `1` worker at local mode.
 - `--sticky` start a sticky cluster server, default to `false`.
 

src/cmd/dev.ts

@@ -55,19 +55,36 @@ export class DevCommand extends BaseCommand {
   }
 
   protected async formatEggStartOptions() {
-    if (!this.port) {
-      const defaultPort = process.env.EGG_BIN_DEFAULT_PORT ?? 7001;
-      debug('detect available port');
-      this.port = await detect(defaultPort);
-      if (this.port !== defaultPort) {
-        console.warn('[egg-bin] server port %s is in use, now using port %o', defaultPort, this.port);
-      }
-      debug(`use available port ${this.port}`);
-    }
     this.framework = utils.getFrameworkPath({
       framework: this.framework,
       baseDir: this.base,
     });
+
+    if (!this.port) {
+      let configuredPort;
+      try {
+        const configuration = utils.getConfig({
+          framework: this.framework,
+          baseDir: this.base,
+          env: 'local',
+        });
+        configuredPort = configuration?.cluster?.listen?.port;
+      } catch (_) { /** skip when failing to read the configuration */ }
+
+      if (configuredPort) {
+        this.port = configuredPort;
+        debug(`use port ${this.port} from configuration file`);
+      } else {
+        const defaultPort = process.env.EGG_BIN_DEFAULT_PORT ?? 7001;
+        debug('detect available port');
+        this.port = await detect(defaultPort);
+        if (this.port !== defaultPort) {
+          console.warn('[egg-bin] server port %s is in use, now using port %o', defaultPort, this.port);
+        }
+        debug(`use available port ${this.port}`);
+      }
+    }
+
     return {
       baseDir: this.base,
       workers: this.workers,

test/cmd/dev.test.ts

@@ -174,4 +174,16 @@ describe('test/cmd/dev.test.ts', () => {
         .end(done);
     });
   });
+
+  describe('obtain the port from config.*.js', () => {
+    const cwd = path.join(fixtures, 'example-port');
+    it('should obtain the port from config.default.js', () => {
+      coffee.fork(eggBin, [ 'dev' ], {
+        cwd,
+      })
+        .expect('stdout', /"port":6001/)
+        .expect('code', 0)
+        .end();
+    });
+  });
 });

test/fixtures/example-port/app/router.js

@@ -0,0 +1,7 @@
+'use strict';
+
+module.exports = app => {
+  app.get('/', ctx => {
+    ctx.body = 'hi, egg';
+  });
+};

test/fixtures/example-port/config/config.default.js

@@ -0,0 +1,9 @@
+'use strict';
+
+exports.key = '12345';
+
+exports.cluster = {
+    listen: {
+        port: 6001,
+    },
+};

test/fixtures/example-port/package.json

@@ -0,0 +1,3 @@
+{
+  "name": "example"
+}