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Async Await in Swift

 Async await came as a part of Swift 5.5 version. If you have a background in JavaScript then you might be aware of these two keywords.


Use Case

Let's say we are getting json in the below format.

{
  "ids": [
    "av234",
    "vasant"
  ]
}

The above json is having, a parameter "ids" which contains the array of article id's. We will take the first id and pass to another service endpoint to get the article details. Below is the json from second service.



{
  "id": "av234",
  "content": "Lorem ipsum",
  "date": "03/05/2022",
  "image_url": "https://google.com/some_image.png"
} 

Now we have to get the image by calling the "image_url" parameter. So totally we have to do three service calls.

Using async await




Using escaping closure

Below is the code for service calls for escaping closure. I have written a class ApiCalls which is having three functions which take escaping closures.



Here is the code to call the above api's using escaping closure and update the UI.



As you can see with the help of async await, the code is  much simpler and easier to understand. In the next article we are going to see some about async await, it's advantages and disadvantages.

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