refactor: implement Loader instead of loading (#4)

lib/base_loader.js

@@ -4,9 +4,9 @@ const fs = require('fs');
 const path = require('path');
 const assert = require('assert');
 const isFunction = require('is-type-of').function;
-const loading = require('loading');
 const interopRequire = require('interop-require');
 const debug = require('debug')('egg:loader');
+const Loader = require('./loader');
 
 class EggLoader {
 
@@ -129,10 +129,8 @@ class EggLoader {
     opt = Object.assign({ lowercaseFirst: true }, opt);
     const controllerBase = path.join(this.options.baseDir, 'app/controller');
 
-    delete app.controller;
-    app.controller = {};
-
-    loading(controllerBase, opt).into(app, 'controller');
+    this.loadToApp(controllerBase, 'controller', opt);
+    app.controllers = app.controller;
     app.coreLogger.info('[egg:loader] Controller loaded: %s', controllerBase);
   }
 
@@ -285,6 +283,20 @@ class EggLoader {
     throw new Error('Can not get appname from package.json');
   }
 
+  loadTo(directory, target, opt) {
+    opt = Object.assign({}, {
+      directory,
+      target,
+      inject: this.app,
+    }, opt);
+    new Loader(opt).load();
+  }
+
+  loadToApp(directory, field, opt) {
+    const target = this.app[field] = {};
+    this.loadTo(directory, target, opt);
+  }
+
 }
 
 /**

lib/loader.js

@@ -0,0 +1,135 @@
+'use strict';
+
+const assert = require('assert');
+const fs = require('fs');
+const debug = require('debug')('egg-loader:loader');
+const path = require('path');
+const globby = require('globby');
+const interopRequire = require('interop-require');
+const is = require('is-type-of');
+const FULLPATH = Symbol('EGG_LOADER_ITEM_FULLPATH');
+
+const defaults = {
+  directory: null,
+  target: null,
+  ignore: undefined,
+  lowercaseFirst: false,
+  initializer: null,
+  call: true,
+  override: false,
+  inject: undefined,
+};
+
+class Loader {
+
+  constructor(options) {
+    assert(options.directory, 'options.directory is required');
+    assert(options.target, 'options.target is required');
+    this.options = Object.assign({}, defaults, options);
+  }
+
+  load() {
+    const items = this.parse();
+    const target = this.options.target;
+    for (const item of items) {
+      debug('loading item %j', item);
+      item.properties.reduce((target, property, index) => {
+        let obj;
+        const properties = item.properties.slice(0, index + 1).join('.');
+        if (index === item.properties.length - 1) {
+          if (property in target) {
+            if (!this.options.override) throw new Error(`can't overwrite property '${properties}' from ${target[property][FULLPATH]} by ${item.fullpath}`);
+          }
+          obj = item.exports;
+          if (obj) obj[FULLPATH] = item.fullpath;
+        } else {
+          obj = target[property] || {};
+        }
+        target[property] = obj;
+        debug('loaded %s', properties);
+        return obj;
+      }, target);
+    }
+    return target;
+  }
+
+  parse() {
+    const files = [ '**/*.js' ];
+    if (typeof this.options.ignore === 'string') {
+      files.push('!' + this.options.ignore);
+    }
+
+    let directories = this.options.directory;
+    if (!Array.isArray(directories)) {
+      directories = [ directories ];
+    }
+
+    const items = [];
+    debug('parsing %j', directories);
+    for (const directory of directories) {
+      const filepaths = globby.sync(files, { cwd: directory });
+      for (const filepath of filepaths) {
+        const fullpath = path.join(directory, filepath);
+        if (!fs.statSync(fullpath).isFile()) {
+          continue;
+        }
+        const properties = getProperties(filepath, this.options.lowercaseFirst);
+        const exports = getExports(fullpath, this.options.initializer, this.options.call, this.options.inject);
+        if (exports == null) continue;
+        items.push({ fullpath, properties, exports });
+        debug('parse %s, properties %j, export %j', fullpath, properties, exports);
+      }
+    }
+
+    return items;
+  }
+
+}
+
+module.exports = Loader;
+
+// a/b/c.js => ['a', 'b', 'c']
+function getProperties(filepath, lowercaseFirst) {
+  return filepath
+  .replace('.js', '')
+  .split('/')
+  .map(function(property) {
+    if (!/^[a-z][a-z0-9_-]*$/i.test(property)) {
+      throw new Error(`${property} is not match 'a-z0-9_-' in ${filepath}`);
+    }
+    let result = property.replace(/[_-][a-z]/ig, function(s) {
+      return s.substring(1).toUpperCase();
+    });
+    if (lowercaseFirst) {
+      result = result[0].toLowerCase() + result.substring(1);
+    }
+    return result;
+  });
+}
+
+function getExports(fullpath, initializer, isCall, inject) {
+  let exports;
+  try {
+    exports = interopRequire(fullpath);
+  } catch (err) {
+    err.message = 'load file: ' + fullpath + ', error: ' + err.message;
+    throw err;
+  }
+
+  if (initializer) {
+    exports = initializer(exports);
+  }
+
+  if (is.class(exports) || is.generatorFunction(exports)) {
+    return exports;
+  }
+
+  if (isCall && is.function(exports)) {
+    exports = exports(inject);
+    if (exports != null) {
+      return exports;
+    }
+  }
+
+  return exports;
+}

lib/middleware_loader.js

@@ -1,7 +1,6 @@
 'use strict';
 
 const join = require('path').join;
-const loading = require('loading');
 const is = require('is-type-of');
 const debug = require('debug')('egg:loader:middleware');
 const inspect = require('util').inspect;
@@ -36,8 +35,7 @@ module.exports = {
     }, opt);
     const middlewarePaths = this.loadDirs().map(dir => join(dir, 'app/middleware'));
 
-    delete app.middlewares;
-    loading(middlewarePaths, opt).into(app, 'middlewares');
+    this.loadToApp(middlewarePaths, 'middlewares', opt);
 
     app.coreLogger.info('Use coreMiddleware order: %j', this.config.coreMiddleware);
     app.coreLogger.info('Use appMiddleware order: %j', this.config.appMiddleware);

lib/proxy_loader.js

@@ -1,7 +1,6 @@
 'use strict';
 
 const join = require('path').join;
-const loading = require('loading');
 const classLoader = Symbol('classLoader');
 const utils = require('./utils');
 
@@ -21,8 +20,7 @@ module.exports = {
     opt = Object.assign({ call: true, lowercaseFirst: true }, opt);
     const arr = this.loadDirs().map(dir => join(dir, 'app/proxy'));
     // load proxy classes to app.proxyClasses
-    delete app.proxyClasses;
-    loading(arr, opt).into(app, 'proxyClasses');
+    this.loadToApp(arr, 'proxyClasses', opt);
 
     // this.proxy.demoQuery.getUser(uid)
     Object.defineProperty(app.context, 'proxy', {

lib/service_loader.js

@@ -1,7 +1,6 @@
 'use strict';
 
 const path = require('path');
-const loading = require('loading');
 const utils = require('./utils');
 const classLoader = Symbol('classLoader');
 
@@ -18,15 +17,14 @@ module.exports = {
    */
   loadService(opt) {
     const app = this.app;
-    opt = Object.assign({ call: false, lowercaseFirst: true }, opt);
     const servicePaths = this.loadDirs().map(dir => {
       const servicePath = path.join(dir, 'app/service');
       return servicePath;
     });
 
     // 载入到 app.serviceClasses
-    delete app.serviceClasses;
-    loading(servicePaths, opt).into(app, 'serviceClasses');
+    opt = Object.assign({ call: false, lowercaseFirst: true }, opt);
+    this.loadToApp(servicePaths, 'serviceClasses', opt);
 
     /**
      * 可以访问到当前应用配置的所有 service，

package.json

@@ -37,15 +37,16 @@
     "koa": "1",
     "koa-router": "4",
     "mm": "1",
+    "pedding": "^1.0.0",
     "should": "9",
     "supertest": "1"
   },
   "dependencies": {
     "debug": "^2.2.0",
     "depd": "^1.1.0",
     "extend": "^3.0.0",
+    "globby": "^6.0.0",
     "interop-require": "^1.0.0",
-    "is-type-of": "^1.0.0",
-    "loading": "^1.12.0"
+    "is-type-of": "^1.0.0"
   }
-}
+}

test/fixtures/load_dirs/babel/UserProxy.js

@@ -0,0 +1,32 @@
+'use strict';
+
+var _temporalUndefined = {};
+
+var _createClass = (function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ('value' in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; })();
+
+var UserProxy = _temporalUndefined;
+
+function _temporalAssertDefined(val, name, undef) { if (val === undef) { throw new ReferenceError(name + ' is not defined - temporal dead zone'); } return true; }
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError('Cannot call a class as a function'); } }
+
+UserProxy = (function () {
+  function UserProxy() {
+    _classCallCheck(this, _temporalAssertDefined(UserProxy, 'UserProxy', _temporalUndefined) && UserProxy);
+
+    this.user = {
+      name: 'xiaochen.gaoxc'
+    };
+  }
+
+  _createClass(_temporalAssertDefined(UserProxy, 'UserProxy', _temporalUndefined) && UserProxy, [{
+    key: 'getUser',
+    value: function getUser() {
+      return this.user;
+    }
+  }]);
+
+  return _temporalAssertDefined(UserProxy, 'UserProxy', _temporalUndefined) && UserProxy;
+})();
+
+module.exports = _temporalAssertDefined(UserProxy, 'UserProxy', _temporalUndefined) && UserProxy;

test/fixtures/load_dirs/class/UserProxy.js

@@ -0,0 +1,15 @@
+'use strict';
+
+class UserProxy {
+  constructor() {
+    this.user = {
+      name: 'xiaochen.gaoxc',
+    };
+  }
+
+  getUser() {
+    return this.user;
+  }
+}
+
+module.exports = UserProxy;

test/fixtures/load_dirs/dao/TestClass.js

@@ -0,0 +1,9 @@
+'use strict';
+
+module.exports = class TestClass {
+  constructor() {
+    this.user = {
+      name: 'kai.fangk',
+    };
+  }
+}

test/fixtures/load_dirs/dao/testFunction.js

@@ -0,0 +1,9 @@
+'use strict';
+
+module.exports = function(obj) {
+  return {
+    user: {
+      name: 'kai.fangk',
+    },
+  };
+};

test/fixtures/load_dirs/dao/testReturnFunction.js

@@ -0,0 +1,11 @@
+'use strict';
+
+module.exports = function(obj) {
+  return function() {
+    return {
+      user: {
+        name: 'kai.fangk',
+      },
+    }
+  };
+};

test/fixtures/load_dirs/es6_module/mod.js

@@ -0,0 +1,6 @@
+'use strict';
+
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.default = function() {
+  return { a: 1 };
+};

test/fixtures/load_dirs/ignore/a.js

@@ -0,0 +1,3 @@
+module.exports = function() {
+  return { a: 1 };
+};

test/fixtures/load_dirs/ignore/util/a.js

@@ -0,0 +1,4 @@
+module.exports = {
+  method1: function() {
+  }
+};

test/fixtures/load_dirs/ignore/util/b/b.js

@@ -0,0 +1 @@
+module.exports = { b: 2 };

test/fixtures/load_dirs/lowercase/SomeClass.js

@@ -0,0 +1,5 @@
+exports.getByName = function (name, callback) {
+  setTimeout(function () {
+    callback(null, {name: name});
+  }, 1);
+};

test/fixtures/load_dirs/lowercase/SomeDir/SomeSubClass.js

@@ -0,0 +1,5 @@
+exports.getByName = function (name, callback) {
+  setTimeout(function () {
+    callback(null, {name: name});
+  }, 1);
+};

test/fixtures/load_dirs/middlewares/app/m1.js

@@ -0,0 +1 @@
+module.exports = function () {};

test/fixtures/load_dirs/middlewares/app/m2.js

@@ -0,0 +1 @@
+module.exports = function () {};

test/fixtures/load_dirs/middlewares/default/dm1.js

@@ -0,0 +1 @@
+module.exports = function () {};

test/fixtures/load_dirs/middlewares/default/dm2.js

@@ -0,0 +1 @@
+module.exports = function () {};

test/fixtures/load_dirs/middlewares/default/session.js

@@ -0,0 +1 @@
+module.exports = function () {};