Tips for patiently waiting for a method to be executed

Question

Tips for patiently waiting for a method to be executed

I have encountered a situation where I need to ensure that the result of two methods is awaited before proceeding with the rest of the code execution. I attempted to use the async keyword before the function name and await before the GetNavigationData() method, but unfortunately, this did not yield the desired results. In an effort to troubleshoot, I also attempted to print out the values to understand what was happening. The expected data should be:

API method

Regular method

However, the actual results are as follows: https://i.sstatic.net/EAi6U.png

getFlatNavigation(navigation) {
  if (this.navigation.length == 0) {
    console.log(this.GetNavigationData());
    console.log('Regular method');
  }
}

GetNavigationData() {
  let applicationMenuData = new InitializeAppRequest();
  this.http.post(this.appGlobal.BASE_SERVER_ADDRESS + 'api/AppServer/InitializeApp', applicationMenuData).subscribe((res) => {
    console.log('API method');
    return res['AplicationMenuData'];
  });
}

What steps should be taken in order to achieve the expected results?

angular rest typescript api

Answer 1

Answer №1

To optimize your code, consider using async/await for better performance:

async fetchUserMenu(navigation) {
  if (this.navigation.length == 0) {
    console.log(await this.retrieveUserData());
    console.log('Using regular method');
  }
}

retrieveUserData() {
  let menuData = new InitializeAppRequest();
  return this.http
    .post(this.appGlobal.BASE_SERVER_ADDRESS + 'api/AppServer/InitializeApp', menuData)
    .pipe(
      map((res) => {
        console.log('Calling API method');
        return res['UserData'];
      })
    )
    .toPromise();
}

Answer 2

To optimize your code, consider using async/await for better performance:

async fetchUserMenu(navigation) {
  if (this.navigation.length == 0) {
    console.log(await this.retrieveUserData());
    console.log('Using regular method');
  }
}

retrieveUserData() {
  let menuData = new InitializeAppRequest();
  return this.http
    .post(this.appGlobal.BASE_SERVER_ADDRESS + 'api/AppServer/InitializeApp', menuData)
    .pipe(
      map((res) => {
        console.log('Calling API method');
        return res['UserData'];
      })
    )
    .toPromise();
}

Answer 3

Answer №2

async fetchNavigationInfo(navData) {
  if (this.navigationList.length == 0) {
    console.log(await this.retrieveNavigationData());
    console.log('Standard procedure');
  }
}

async retrieveNavigationData() {
  let menuData = new InitializeAppRequest();
  this.http.post(this.appGlobal.BASE_SERVER_ADDRESS + 'api/AppServer/InitializeApp', menuData).subscribe((res) => {
    console.log('API approach');
    return res['AplicationMenuData'];
  });
}

Answer 4

async fetchNavigationInfo(navData) {
  if (this.navigationList.length == 0) {
    console.log(await this.retrieveNavigationData());
    console.log('Standard procedure');
  }
}

async retrieveNavigationData() {
  let menuData = new InitializeAppRequest();
  this.http.post(this.appGlobal.BASE_SERVER_ADDRESS + 'api/AppServer/InitializeApp', menuData).subscribe((res) => {
    console.log('API approach');
    return res['AplicationMenuData'];
  });
}

Answer 5

Answer №3

async and await may require the use of Promise, but now that Angular has implemented Observables, you have the option to simplify your syntax by using them instead.

In the getFlatNavigation method, you can return an Observable from GetNavigationData and then subscribe to it when calling GetNavigationData.

getFlatNavigation(navigation) {
  if (this.navigation.length == 0) {
    this.GetNavigationData()
      .subscribe(res => {
        console.log(res);
        console.log('Regular method');
      })
  }
}

GetNavigationData() {
  let applicationMenuData = new InitializeAppRequest();
  return this.http.post(this.appGlobal.BASE_SERVER_ADDRESS + 'api/AppServer/InitializeApp', applicationMenuData)
  .pipe(
    map(res => {
      console.log('API method');
      return res['ApplicationMenuData'];
    })
  );
}

Answer 6

async and await may require the use of Promise, but now that Angular has implemented Observables, you have the option to simplify your syntax by using them instead.

In the getFlatNavigation method, you can return an Observable from GetNavigationData and then subscribe to it when calling GetNavigationData.

getFlatNavigation(navigation) {
  if (this.navigation.length == 0) {
    this.GetNavigationData()
      .subscribe(res => {
        console.log(res);
        console.log('Regular method');
      })
  }
}

GetNavigationData() {
  let applicationMenuData = new InitializeAppRequest();
  return this.http.post(this.appGlobal.BASE_SERVER_ADDRESS + 'api/AppServer/InitializeApp', applicationMenuData)
  .pipe(
    map(res => {
      console.log('API method');
      return res['ApplicationMenuData'];
    })
  );
}

Tips for patiently waiting for a method to be executed

Answer №1

Answer №2

Answer №3

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