@lvl/wxapp-cli/lib/utils/env.js

wxapp-cli

const { execSync } = require('child_process')
const fse = require('fs-extra')
const { resolve } = require('path')
const LRU = require('lru-cache')
const chalk = require('chalk')
const { cliRoot } = require('../config/wxapp-cli.config')

let _hasGit
const _gitProjects = new LRU({
  max: 10,
  maxAge: 1000
})

exports.hasGit = () => {
  if (_hasGit != null) {
    return _hasGit
  }
  try {
    execSync('git --version', { stdio: 'ignore' })
    return (_hasGit = true)
  } catch (e) {
    return (_hasGit = false)
  }
}

exports.hasProjectGit = (cwd) => {
  if (_gitProjects.has(cwd)) {
    return _gitProjects.get(cwd)
  }

  let result
  try {
    execSync('git status', { stdio: 'ignore', cwd })
    result = true
  } catch (e) {
    result = false
  }
  _gitProjects.set(cwd, result)
  return result
}

exports.setProjectGit = (cwd, val) => {
  _gitProjects.set(cwd, val)
}

exports.getAppCtx = (cwd = '') => {
  let res = null
  while (cwd && cwd !== '/') {
    res = fse.pathExistsSync(resolve(`${cwd}`, 'wxapp-cli.config.js'))
    if (res) {
      return cwd
    } else {
      cwd = resolve(cwd, '../')
    }
  }
  return null
}

exports.prepareEnv = async () => {
  const appCtx = exports.getAppCtx(process.cwd())
  if (!appCtx) {
    console.error(chalk.red(`请在 wxapp-cli 创建的项目中执行此命令`))
    process.exit(1)
  }

  const cliTplConfig = require(resolve(appCtx, 'wxapp-cli.config'))

  const tplModuleName = cliTplConfig.template.module
  const version = cliTplConfig.template.version

  let cliTemplate = null
  try {
    cliTemplate = require(tplModuleName)
  } catch (err) {}
  if (!cliTemplate || cliTemplate.version !== version) {
    // 将模版切换到项目指定的版本
    execSync(`npm install ${tplModuleName}@${version} --no-save --unsafe-perm`, {
      cwd: cliRoot,
      stdio: 'inherit'
    })
    purgeCache(tplModuleName)
    cliTemplate = require(tplModuleName)
  }

  return {
    appCtx,
    cliTplConfig,
    cliTemplate
  }
}

/**
 * 从缓存中移除module
 */
function purgeCache(moduleName) {
	// 遍历缓存来找到通过指定模块名载入的文件
	searchCache(moduleName, function (mod) {
		delete require.cache[mod.id];
	});

	// 删除模块缓存的路径
	Object.keys(module.constructor._pathCache).forEach(function (cacheKey) {
		if (cacheKey.indexOf(moduleName) > 0) {
			delete module.constructor._pathCache[cacheKey];
		}
	});
};

/**
 * 遍历缓存来查找通过特定模块名缓存下的模块
 */
function searchCache(moduleName, callback) {
	//  通过指定的名字resolve模块
	var mod = require.resolve(moduleName);

	// 检查该模块在缓存中是否被resolved并且被发现
	if (mod && ((mod = require.cache[mod]) !== undefined)) {
		// 递归的检查结果
		(function traverse(mod) {
			// 检查该模块的子模块并遍历它们
			mod.children.forEach(function (child) {
				traverse(child);
			});

			// 调用指定的callback方法，并将缓存的module当做参数传入
			callback(mod);
		}(mod));
	}
};

exports.purgeCache = purgeCache