From 72f1b363b15acd3da8f17273ff1f7e65b1f467af Mon Sep 17 00:00:00 2001
From: legendecas <legendecas@gmail.com>
Date: Mon, 17 Feb 2020 12:06:18 +0800
Subject: [PATCH] feat(build): options to minify all products

---
 packages/midway-bin/lib/cmd/build.js          | 74 +++++++++++++++++++
 .../midway-bin/test/lib/cmd/build.test.js     | 17 +++++
 2 files changed, 91 insertions(+)

diff --git a/packages/midway-bin/lib/cmd/build.js b/packages/midway-bin/lib/cmd/build.js
index 84797ad23791..26a5e0217af1 100644
--- a/packages/midway-bin/lib/cmd/build.js
+++ b/packages/midway-bin/lib/cmd/build.js
@@ -3,12 +3,16 @@
 const Command = require('egg-bin').Command;
 const path = require('path');
 const fs = require('fs');
+const fsPromise = fs.promises;
 const rimraf = require('mz-modules/rimraf');
 const fse = require('fs-extra');
 const globby = require('globby');
 const ncc = require('@midwayjs/ncc');
+const typescript = require('typescript');
+const terser = require('terser');
 
 const shebangRegEx = /^#![^\n\r]*[\r\n]/;
+const inlineSourceMapRegEx = /\/\/# sourceMappingURL=data:application\/json;base64,(.*)/;
 
 class BuildCommand extends Command {
   constructor(rawArgv) {
@@ -37,6 +41,9 @@ class BuildCommand extends Command {
         type: 'string',
         default: '',
       },
+      minify: {
+        type: 'boolean',
+      },
       mode: {
         description: 'bundle mode, "debug" or "release" (default)',
         type: 'string',
@@ -94,6 +101,10 @@ class BuildCommand extends Command {
       args.push(argv.project);
     }
     await this.helper.forkNode(tscCli, args, { cwd, execArgv: [] });
+
+    if (argv.minify) {
+      await this.minify(tsConfig, outDirAbsolute);
+    }
   }
 
   async bundle(entry, outDir, { sourceMap = false, mode } = {}) {
@@ -207,6 +218,69 @@ class BuildCommand extends Command {
       return tsConfig.compilerOptions[optionKeyPath];
     }
   }
+
+  async minify(tsConfig, outDir) {
+    const inlineSourceMap = !!tsConfig.compilerOptions.inlineSourceMap;
+    const sourceMap = inlineSourceMap || tsConfig.compilerOptions.sourceMap;
+    if (!sourceMap) {
+      return;
+    }
+
+    let files;
+    if (outDir) {
+      files = globby.sync([ '**/*.js' ], {
+        cwd: outDir,
+        ignore: [ '**/node_modules' ],
+      });
+      files = files.map(it => path.join(outDir, it));
+    } else {
+      const host = typescript.createCompilerHost(tsConfig.compilerOptions);
+      files = host.readDirectory(__dirname, [ '.ts' ], tsConfig.exclude, tsConfig.include);
+      files = files.map(it => {
+        return path.join(path.dirname(it), path.basename(it, '.js'));
+      });
+    }
+
+    for (const file of files) {
+      let code = await fsPromise.readFile(file, 'utf8');
+      let map;
+      if (inlineSourceMap) {
+        map = this.parseInlineSourceMap(code);
+      } else {
+        map = await fsPromise.readFile(file + '.map', 'utf8');
+      }
+      map = JSON.parse(map);
+      const result = terser.minify(code, {
+        compress: false,
+        mangle: {
+          keep_classnames: true,
+          keep_fnames: true,
+        },
+        sourceMap: {
+          content: map,
+          filename: path.basename(file),
+          url: inlineSourceMap ? 'inline' : `${path.basename(file)}.map`,
+        },
+      });
+      ({ code, map } = result);
+      if (code == null) {
+        break;
+      }
+      if (!inlineSourceMap) {
+        await fsPromise.writeFile(file + '.map', map, 'utf8');
+      }
+      await fsPromise.writeFile(file, code, 'utf8');
+    }
+  }
+
+  parseInlineSourceMap(code) {
+    const match = inlineSourceMapRegEx.exec(code);
+    if (match == null) {
+      return;
+    }
+    const map = Buffer.from(match[1], 'base64').toString('utf8');
+    return map;
+  }
 }
 
 module.exports = BuildCommand;
diff --git a/packages/midway-bin/test/lib/cmd/build.test.js b/packages/midway-bin/test/lib/cmd/build.test.js
index 9c83645dae80..73162ddf214b 100644
--- a/packages/midway-bin/test/lib/cmd/build.test.js
+++ b/packages/midway-bin/test/lib/cmd/build.test.js
@@ -170,3 +170,20 @@ describe('test/lib/cmd/build.test.js - bundling', () => {
     await rimraf(path.join(cwd, 'dist'));
   });
 });
+
+describe('test/lib/cmd/build.test.js - minify', () => {
+  const midwayBin = require.resolve('../../../bin/midway-bin.js');
+  const argv = [ 'build', '-c', '--minify'];
+
+  afterEach(mm.restore);
+
+  it('should build success', async () => {
+    const cwd = path.join(__dirname, '../../fixtures/ts-dir');
+    await rimraf(path.join(cwd, 'dist'));
+    const child = coffee.fork(midwayBin, argv, { cwd });
+    await child.expect('code', 0).end();
+    assert(fs.existsSync(path.join(cwd, 'dist/a.js')));
+    assert(/\/\/# sourceMappingURL/.exec(fs.readFileSync(path.join(cwd, 'dist/a.js'), 'utf8')));
+    await rimraf(path.join(cwd, 'dist'));
+  });
+});