javascript - 在 TypeScript 中包装 Firebase promise

Question

我正在尝试将两个函数转换为更多的 DRY 代码:

  async registerUser(newUser: User) {
    await this.db.auth
      .createUserWithEmailAndPassword(newUser.email, newUser.pass)
      .then(data => {
        this.db.auth.currentUser.getIdToken().then(reply => {
          this.http
            .post('http://localhost:3000/login', { token: reply })
            .toPromise()
            .then(response => {
              if (response['valid'] === 'true') {
                localStorage.setItem('user', JSON.stringify(reply));
                this.router.navigate(['dash']);
              }
            });
        });
      })
      .catch(err => {
        console.log('registration failed: ' + err.message);
      });
  }

  async signIn(newUser: User) {
    await this.db.auth
      .signInWithEmailAndPassword(newUser.email, newUser.pass)
      .then(data => {
        this.db.auth.currentUser.getIdToken().then(reply => {
          this.http
            .post('http://localhost:3000/login', { token: reply })
            .toPromise()
            .then(response => {
              if (response['valid'] === 'true') {
                localStorage.setItem('user', JSON.stringify(reply));
                this.router.navigate(['dash']);
              }
            });
        });
      })
      .catch(err => {
        console.log('signIn failed: ' + err.message);
      });
  }

我想创建一个单独的方法来包装这两种方法，这样我就可以重复使用相同的代码。我正在写一个方法，这是我目前所拥有的，这就是我需要问这个问题的时候。我不确定如何最好地结合这些方法，因为我不熟悉 promise 。我应该在这两个 promise 的 resolve() 部分中返回什么以使我的新方法正常工作？

  async useAuth(user: User, action: string) {
    if (action === 'signIn') {
      return await new Promise((resolve, reject) => {
        this.db.auth.signInWithEmailAndPassword(user.email, user.pass);
      });
    } else if (action === 'register') {
      return await new Promise((resolve, reject) => {
        this.db.auth.createUserWithEmailAndPassword(user.email, user.pass);
      });
    }

Answer 1

两个函数都已经返回一个 Promise<UserCredential> .因此，无需将它们包装在另一个 Promise 中。

async useAuth(user: User, action: string) 
{
    let result; // type is UserCredential

    if (action === 'signIn') 
    {
      result = await this.db.auth.signInWithEmailAndPassword(user.email, user.pass);
    } 
    else if (action === 'register') 
    {
      result = await this.db.auth.createUserWithEmailAndPassword(user.email, user.pass);
    }
    else
    {
        throw "unknown action " + action;
    }

    return result;
}