How do I orchestrate async tasks

Ignition
1

I don’t have a Java background so maybe what I’m asking is more of a Java question than an Ignition question.

How do I handle a collection of async calls? I have a bunch of API calls to make and I want to use system.net.httpClient().getAsync every x minutes. The individual calls are unrelated other than the desired frequency.

How do I orchestrate the calls? I’d like to know when everything has completed.

C# Task.WhenAll() is what I have in mind. Don’t know the equivalent concept in Ignition / Java.

Reference: Task.WhenAll Method (System.Threading.Tasks) | Microsoft Learn

2

It's possible that this could be of use to you:

3

The key is that the promise is a thin wrapper around a Java CompletableFuture. Which implements the CompletionStage interface, that has numerous ways to combine results with further actions. The promise wrapper exposes the most import one: .whenComplete(), that takes a function of two arguments. This is the BiConsumer<> async interface. You should create a class implementing BiConsumer with the tracking/counting/accounting logic you wish, and attach it to each promise.

4

The most equivalent would probably be CompletableFuture.allOf, using the underlying CompletableFuture on the Promise as Phil already called out.

5

The downside to .allOf() is that you can't construct it incrementally. A well-designed consumer class could accept more promises while earlier ones are running and completing. Such a class can also process the results as it goes.

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6

I recently needed to create some scripting to execute a task x times in parallel, but block the script from moving on until they completed.

Here is the script incase there's anything useful for you in it.

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