Swift Synchronous API calls











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I have to make three API calls to server one after another(synchronous),second API has to be called only if the first one is success. If first API fails then I have to to stop the flow and show another view controller with retry and cancel. What should I use and How should I do it?






objective-c swift grand-central-dispatch







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  • Use Operation Queue and manage the dependency using OperationQueue
    – HPM
    yesterday








  • 3




    There are more than one solutions to your problem. Here are some keywords that you should be looking for: NSOperation, GCD, futures & promises, async/await pattern. The way that Apple handles this is by operations that depend on other operations. Use of Promises is quite popular for these tasks and finally async/await maybe the cleanest (cognitive load wise) approach to promises (and what I would suggest you to check first)
    – Alladinian
    yesterday

















up vote
-3
down vote

favorite












I have to make three API calls to server one after another(synchronous),second API has to be called only if the first one is success. If first API fails then I have to to stop the flow and show another view controller with retry and cancel. What should I use and How should I do it?






objective-c swift grand-central-dispatch







share|improve this question







New contributor




Revathi Bhavanam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.




















  • Use Operation Queue and manage the dependency using OperationQueue
    – HPM
    yesterday








  • 3




    There are more than one solutions to your problem. Here are some keywords that you should be looking for: NSOperation, GCD, futures & promises, async/await pattern. The way that Apple handles this is by operations that depend on other operations. Use of Promises is quite popular for these tasks and finally async/await maybe the cleanest (cognitive load wise) approach to promises (and what I would suggest you to check first)
    – Alladinian
    yesterday















up vote
-3
down vote

favorite









up vote
-3
down vote

favorite











I have to make three API calls to server one after another(synchronous),second API has to be called only if the first one is success. If first API fails then I have to to stop the flow and show another view controller with retry and cancel. What should I use and How should I do it?






objective-c swift grand-central-dispatch







share|improve this question







New contributor




Revathi Bhavanam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











I have to make three API calls to server one after another(synchronous),second API has to be called only if the first one is success. If first API fails then I have to to stop the flow and show another view controller with retry and cancel. What should I use and How should I do it?






objective-c swift grand-central-dispatch




objective-c swift grand-central-dispatch






share|improve this question







New contributor




Revathi Bhavanam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|improve this question







New contributor




Revathi Bhavanam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|improve this question




share|improve this question






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Revathi Bhavanam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









asked yesterday









Revathi Bhavanam

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11




New contributor




Revathi Bhavanam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





New contributor





Revathi Bhavanam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






Revathi Bhavanam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.












  • Use Operation Queue and manage the dependency using OperationQueue
    – HPM
    yesterday








  • 3




    There are more than one solutions to your problem. Here are some keywords that you should be looking for: NSOperation, GCD, futures & promises, async/await pattern. The way that Apple handles this is by operations that depend on other operations. Use of Promises is quite popular for these tasks and finally async/await maybe the cleanest (cognitive load wise) approach to promises (and what I would suggest you to check first)
    – Alladinian
    yesterday




















  • Use Operation Queue and manage the dependency using OperationQueue
    – HPM
    yesterday








  • 3




    There are more than one solutions to your problem. Here are some keywords that you should be looking for: NSOperation, GCD, futures & promises, async/await pattern. The way that Apple handles this is by operations that depend on other operations. Use of Promises is quite popular for these tasks and finally async/await maybe the cleanest (cognitive load wise) approach to promises (and what I would suggest you to check first)
    – Alladinian
    yesterday


















Use Operation Queue and manage the dependency using OperationQueue
– HPM
yesterday






Use Operation Queue and manage the dependency using OperationQueue
– HPM
yesterday






3




3




There are more than one solutions to your problem. Here are some keywords that you should be looking for: NSOperation, GCD, futures & promises, async/await pattern. The way that Apple handles this is by operations that depend on other operations. Use of Promises is quite popular for these tasks and finally async/await maybe the cleanest (cognitive load wise) approach to promises (and what I would suggest you to check first)
– Alladinian
yesterday






There are more than one solutions to your problem. Here are some keywords that you should be looking for: NSOperation, GCD, futures & promises, async/await pattern. The way that Apple handles this is by operations that depend on other operations. Use of Promises is quite popular for these tasks and finally async/await maybe the cleanest (cognitive load wise) approach to promises (and what I would suggest you to check first)
– Alladinian
yesterday














1 Answer
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Using TRVSURLSessionOperation would help you, here is how to do it:



let queue = OperationQueue()

let session = URLSession(configuration: URLSessionConfiguration.default)

let firstOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "first url")!)) { (data, response, error) in

  // Your completion logic

}

let secondOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "second url")!)) { (data, response, error) in

  // Your completion logic

}

secondOperation?.addDependency(firstOperation!)

queue.addOperations([firstOperation!, secondOperation!], waitUntilFinished: false)





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    up vote
    0
    down vote













    Using TRVSURLSessionOperation would help you, here is how to do it:



    let queue = OperationQueue()
    
let session = URLSession(configuration: URLSessionConfiguration.default)
    
let firstOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "first url")!)) { (data, response, error) in
    
  // Your completion logic
    
}
    
let secondOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "second url")!)) { (data, response, error) in
    
  // Your completion logic
    
}
    
secondOperation?.addDependency(firstOperation!)
    
queue.addOperations([firstOperation!, secondOperation!], waitUntilFinished: false)





    share|improve this answer



























      up vote
      0
      down vote













      Using TRVSURLSessionOperation would help you, here is how to do it:



      let queue = OperationQueue()
      
let session = URLSession(configuration: URLSessionConfiguration.default)
      
let firstOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "first url")!)) { (data, response, error) in
      
  // Your completion logic
      
}
      
let secondOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "second url")!)) { (data, response, error) in
      
  // Your completion logic
      
}
      
secondOperation?.addDependency(firstOperation!)
      
queue.addOperations([firstOperation!, secondOperation!], waitUntilFinished: false)





      share|improve this answer

























        up vote
        0
        down vote










        up vote
        0
        down vote









        Using TRVSURLSessionOperation would help you, here is how to do it:



        let queue = OperationQueue()
        
let session = URLSession(configuration: URLSessionConfiguration.default)
        
let firstOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "first url")!)) { (data, response, error) in
        
  // Your completion logic
        
}
        
let secondOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "second url")!)) { (data, response, error) in
        
  // Your completion logic
        
}
        
secondOperation?.addDependency(firstOperation!)
        
queue.addOperations([firstOperation!, secondOperation!], waitUntilFinished: false)





        share|improve this answer














        Using TRVSURLSessionOperation would help you, here is how to do it:



        let queue = OperationQueue()
        
let session = URLSession(configuration: URLSessionConfiguration.default)
        
let firstOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "first url")!)) { (data, response, error) in
        
  // Your completion logic
        
}
        
let secondOperation = TRVSURLSessionOperation(session: session, request: URLRequest(url: URL(string: "second url")!)) { (data, response, error) in
        
  // Your completion logic
        
}
        
secondOperation?.addDependency(firstOperation!)
        
queue.addOperations([firstOperation!, secondOperation!], waitUntilFinished: false)






        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited yesterday

























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        MuhammadBassio

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