defer

415 bytes

since v12.1.0

使用方法

defer 函数允许您在运行异步函数的同时注册清理函数，这些清理函数将在主函数完成后执行。这在您需要清理资源时很有用，无论主函数成功还是失败，类似于 finally 块。

传递给 defer 的函数接收一个 register 函数作为其参数。使用它来注册应在主函数完成后运行的清理工作。

默认情况下，如果清理函数在主函数已抛出错误后抛出错误，清理错误将被忽略。您可以通过向 register 函数传递 { rethrow: true } 来自定义此行为，让它重新抛出清理错误。

清理临时文件

import * as _ from "radashi";

// 占位函数
const createBuildDir = async () => {
  console.log("Creating build directory...");
  await _.sleep(100);
  console.log("Build directory created.");
  return "build";
};
const build = async () => {
  console.log("Building project...");
  await _.sleep(100);
  console.log("Project built.");
};

await _.defer(async (cleanup) => {
  const buildDir = await createBuildDir();

  cleanup(() => fs.unlink(buildDir));

  await build();
});

在 API 中清理资源

// 占位API
const api = {
  org: {
    create: async () => ({ id: 1 }),
    delete: async () => {
      console.log("Deleting organization...");
      await _.sleep(100);
      console.log("Deleted organization.");
    },
  },
  user: {
    create: async () => ({ id: 2 }),
    delete: async () => {
      console.log("Deleting user...");
      await _.sleep(100);
      console.log("Deleted user.");
    },
  },
};

// 占位测试函数
const executeTest = async () => {
  console.log("Executing test...");
  await _.sleep(100);
  console.log("Test complete.");
};

await _.defer(async (register) => {
  const org = await api.org.create();
  register(async () => api.org.delete(org.id), { rethrow: true });

  const user = await api.user.create();
  register(async () => api.user.delete(user.id), { rethrow: true });

  await executeTest(org, user);
});