builder-isv/models/renderer.js

ISV 模块本地预览与云构建器

/**
 * @author 龙喜<xiaolong.lxl@alibaba-inc.com>
 * @description Renderer
 */

'use strict';

// https://nodejs.org/dist/latest-v6.x/docs/api/events.html
const EventEmitter = require('events');
const path = require('path');
const os = require('os');
const renderConfigLoader = require('../lib/renderConfigLoader');
const config = require('../config');
const utils = require('../lib/utils');
const Base = require('./base');

module.exports = class Renderer extends EventEmitter {
  /**
   * 构造一个构建器
   * @param module 模块信息
   */
  constructor(module) {
    super();

    // 设置上下文
    this.config(module);
  }

  /**
   * 配置上下文
   * @param module 模块信息（INVOKE_TYPE_BUILD 情况下有 outputDir 属性）
   */
  config(module) {
    let rendererConfig = Renderer.getMatchedRendererConfig(module);

    this.id = `${module.moduleType}/${module.moduleName}`;
    //  status: -1(错误) / 0(就绪) / 1（编译中）/ 2（编译成功）
    this.status = 0;
    this.module = module;
    this.rendererConfig = rendererConfig;
    this.outputDir = module.outputDir || path.join(config.defOptions.tmpPreviewDir, module.moduleType);

    utils.log.verbose('outputDir', this.outputDir);

    // 构建器匹配
    if (this.builder && this.rendererConfig.match(module.abcInfo, module.packageInfo)) {
      utils.log.verbose('构建器类型匹配，切换构建入口（entry）');

      this.builder.changeEntry(module);
    } else {
      if (this.builder) {
        this.builder.stop();
        this.builder.destroy();
      }

      let Builder = rendererConfig.getBuilder();

      this.builder = new Builder(module.outputDir ? Base.INVOKE_TYPE_BUILD : Base.INVOKE_TYPE_PREVIEW);

      // 所有事件透传
      this.builder.addListener('compileFailed', (err) => {
        this.status = -1;
        this.error = err;
        this.emit('compileFailed', err);
      });

      this.builder.addListener('compileStart', () => {
        this.status = 1;
        this.emit('compileStart');
      });

      this.builder.addListener('compileSucceed', () => {
        this.status = 2;
        this.error = null;
        this.emit('compileSucceed');
      });

      this.builder.addListener('compileFinished', () => {
        this.emit('compileFinished');
      });
    }
  }

  /**
   * 页面渲染器
   * @param params
   * @param queries
   * @param headers
   * @param {JSONStore} abcInfo
   * @param {JSONStore} packageInfo
   */
  *render(params, queries, headers, abcInfo, packageInfo) {
    return yield this.rendererConfig.render(params, queries, headers, abcInfo, packageInfo);
  }

  /**
   * 开始构建
   */
  build() {
    if (this.status !== 0) {
      throw new Error('构建器已经运行过了');
    }

    this.status = 1;

    // 开始构建
    this.builder.start({
      cwd: this.module.modulePath,
      module: this.module,
      outputDir: this.outputDir
    });
  }

  /**
   * 等待构建完成，构建错误抛出
   * @returns {Promise}
   */
  waitUntilBundleFinished() {
    return new Promise((resolve, reject) => {
      if (this.status === 0 || this.status === 1) {
        this.once('compileFinished', () => {
          if (this.status === -1) {
            reject(this.error);
          } else {
            resolve();
          }
        });
      } else if (this.status === -1) {
        reject(this.error);
      } else {
        resolve();
      }
    });
  }

  /**
   * 获取匹配的渲染器配置
   * @param module
   * @returns {*}
   */
  static getMatchedRendererConfig(module) {
    let abcInfo = module.abcInfo;
    let packageInfo = module.packageInfo;

    for (let i = 0, renderers = renderConfigLoader.renderers; i < renderers.length; ++i) {
      if (renderers[i].match(abcInfo, packageInfo)) {
        return renderers[i];
      }
    }

    throw new Error('找不到匹配的渲染器');
  }
};