在 TypeScript 中包裝 Firebase 承諾

Question

我正在嘗試將兩個函數轉換為更多 DRY 代碼：

  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);
      });
  }

我想創建一個單獨的方法來包裝這兩種方法，這樣我就可以重用相同的代碼。 我正在寫一個方法，這就是我到目前為止所擁有的，這就是我需要提出這個問題的地方。 我不確定如何最好地組合這些方法，因為我不熟悉 promise。 我應該在這兩個承諾的 resolve() 部分返回什么才能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

這兩個函數都已經返回Promise<UserCredential> 。 因此，無需將它們包裝在另一個 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;
}

Answer 2

NineBerry 的答案是正確的，我最終實現了：

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

我是這樣做的！