REST API web query fails to refresh when published, integrate retry

[MegaOctane1]

I have a function which is invoked by another query, and it repeats for each customer number, to retrieve data from an API. it works fine on desktop, but when published it throws the error: "The underlying connection was closed. An unexpected error occured on send".

I want to add a retry to the fuction or query, and not sure how to do it 

this is my function, and i have deleted/changed a the confidential information:

let
  source = (CustomerNumber) =>

    let
      
      host = "https://hiddeninformation.com/api/customer/",
      Path = CustomerNumber & "/invoices?supplierId=99999",

      Source = Json.Document(
        Web.Contents(
          host, 
          [ 
            RelativePath = Path,
            Headers = [
              #"verification-code" = "abcdefgh", 
              #"key"  = "123456789"
            ]
          ]
        )
      )
.
.
.
.
.
in source

[PhilipTreacy · Accepted solution]

Hi @MegaOctane1 

Check your returned data for something that you know should be there, if it isn't then call the function again.  Something like this

.
.
WebQuery = fxWebFunction(CustomerNumber),
CheckQueryResult = if WebQuery[SomeValue] = TRUE then WebQuery else fxWebFunction(CustomerNumber),
WebQueryResult = if CheckQueryResult[SomeValue] = TRUE then CheckQueryResult else "Error",
.
.

I obviously don't know what value you need to test for to see of the query succeeded, you'll have to insert that into the code.

There is try..otherwise built into PQ which is meant to catch errors but it doesn't always work as expected (it doesn't trigger on some errors), and it may not work for you anyway in this scenario as the error is from the web server and may not filter through to the PQ code as an actual error condition.

regards

Phil