How to use async/await in Vue.js?

Question

I'm new in ES7

I want to use async/await in Vue.js

Here is my code

created (){
    this.getA()
    console.log(2)
    this.getB() 
},
methods : {
    getA (){
        console.log(1)
    },
    getB (){
        console.log(3)
    }
}

It returns

1
2
3

But when I use it with axios, then

created (){
    this.getA()
    console.log(2)
    this.getB() 
},
methods : {
    getA (){
        $axios.post(`/getA`,params){
        .then((result) => {
            console.log(1)
        })
    },
    getB (){
        console.log(3)
    }
}

It returns

2
3
1

So I want to add async/await in that code.

How can I use async/await?

I tried

async created (){
    await this.getA()
    console.log(2)
    await this.getB() 
},
methods : {
    getA (){
        $axios.post(`/getA`,params){
        .then((result) => {
            console.log(1)
        })
    },
    getB (){
        console.log(3)
    }
}

It returns same result.

Convulsion

getA doesn't return the promise. – Flyblown

Answer 1

You have to use either then or await not both as shown below:

If using then

created () {
    this.getA().then((result) => {
            console.log(1)
            console.log(2)
            this.getB()
        })
},
methods : {
    getA () {
        return $axios.post(`/getA`,params);
    },
    getB (){
        console.log(3)
    }
}

If using await

async created (){
    await this.getA()
    console.log(1)
    console.log(2)
    this.getB() 
},
methods : {
    getA : async() => {
        return $axios.post(`/getA`,params);
    },
    getB : () => {
        console.log(3)
    }
}

Note that while calling getB() you don't need then or await since it is not asynchronous

Ediva

since getB is not asynchronous, then what is the use of async for getB ? – Yellowtail

Answer 2

Unlike what @thanthu said, you can use both then and await. In your first post you only missed to add return in the getA method:

async created (){
    await this.getA()
    console.log(2)
    await this.getB() 
},
methods : {
    getA() {
        return $axios
            .post(`/getA`,params){
            .then((result) => {
                console.log(1)
            });
    },
    getB() { 
        console.log(3)
    }
}

Intracardiac

you can. But should you? one day you will find yourself in the middle of try-catch and .catch(err => {console.log(err)}) blocks, with tons of async-await and .then and .all instructions. It could be the second most difficult challenge for a gentleman. Of course, after an attempt to give birth to a baby. For women - the most difficult one. – Wintery

it still feels like the way to go, you are awaiting for a promise that ends when console.log(1) run – Aloisius

Answer 3

Vuejs, example with Axios API request. more details between the code

  methods: {
    async getA(data, type) {
      console.log("This is a API calls, that the response time is vary.");

      const result = await this.getSources();
      
      console.log("Do what you want after completing the prev job.");
    },
    getSources() {
      return new Promise(resolve => {

        // Here the point is the resolve that you should resolve('something');.
        this.axios
          .get("/api/sources")
          .then((resp) => {
            this.sources = resp.data;
            resolve('resolved');
          })
          .catch(() => {
            resolve('rejected');
          });
      });
    },
  },

Leopardi

Answer 4

try this

async created (){
    let resultFromgetA = await this.getA()
    console.log(2)
    await this.getB() 
},
methods : {
    getA :() =>{
        return $axios.post(`/getA`,params);
    },
    getB : async() =>{
        //use await key with async calls
        console.log(3)
    }
}

Theocracy

adding async to created lifecycle method made it work for me while having a chained promises procedure. – Conceal