⚡️ Fast async task based Swift framework with focus on type safety, concurrency and multi threading

Overdrive: 0.2.2 Package manager (SPM, Carthage, CocoaPods, Manual): CocoaPods Xcode: 8.3.1 Platform: iOS

Hi @arikis,

The project I'm working on requires Overdrive to work, and while I know I'm not supposed to be asking for ETAs around here, I wanted to know if we can just release a minor bumped version of Overdrive (maybe 0.2.3) with mainly the task observer memory leak fixed. I would be happy to help in any way I can.

Overdrive: 0.2.2 Package manager (SPM, Carthage, CocoaPods, Manual): CocoaPods Xcode: 8.2.1 Platform: iOS

Are there any plans for supporting repeat dependencies? For example, if I add a task A which depends on the task Z, both Z and A get added to the queue.

Now, if I have a task B, which depends on the same instance of task Z as earlier, and I add B, it crashes because I have added the same instance of task Z again to the queue.

What could be the other behaviour is that when Z came in the first time, Z would have been added to the queue, but the second time, Z would have simply been added as a dependency for B.

Let me know if this is too specific to my requirements, or it's something we can have at Overdrive level?

Overdrive: 0.2.2 Package manager (SPM, Carthage, CocoaPods, Manual): CocoaPods Xcode: 8.0 Platform: iOS 10.0

Hi,

Following your test class, I wrote a basic example:

// Custom Task
class ImageTask: Task<UIImage> {
    
    override func run() {

        let logoURL = URL(string: "http://i2.cdn.cnn.com/cnnnext/dam/assets/161217142430-2017-cars-ferrari-1-exlarge-169.jpg")!
        
        do {
            let logoData = try Data(contentsOf: logoURL)
            let image = UIImage(data: logoData)!
            finish(with: .value(image)) // finish with image
            
        } catch {
            finish(with: .error(error)) // finish with error if any
        }
    }
    
}

// Custom Task Queue
class CustomTaskQueue: TaskQueueDelegate {
    private var queue:TaskQueue
    
    public init() {
        self.queue = TaskQueue(qos: .default)
        self.queue.delegate = self
    }
    
    public func start() {
        let t1 = ImageTask()
        t1.name = "Image Task"
        t1.onValue { image in
            print("image downloaded \(image)")
        }
        
        t1.onError { error in
            print("image error \(error.localizedDescription)")
        }
        
        self.queue.add(task: t1)
    }
    
    func didAdd<T>(task: Task<T>, toQueue queue: TaskQueue) {
        print("task did add \(task.name)")
    }
    
    func didFinish<T>(task: Task<T>, inQueue queue: TaskQueue) {
        print("task did finish \(task.name)")
    }
    
}

And then call it via the following lines:

let taskQueue = CustomTaskQueue()
taskQueue.start()

The Xcode terminal log output:

task did add Optional("Image Task")
image downloaded <UIImage: 0x61800008f0a0>, {780, 438}

I can't receive the end message task did finish Optional("Image Task") when a task has been finished. I listen to the didFinish<T>(task: Task<T>, inQueue queue: TaskQueue) method but nothing happens. Did I make a mistake ?

Thank you in advance

Overdrive: 0.2.1 Package manager (SPM, Carthage, CocoaPods, Manual): Cocoapods 1.1 Xcode: 8.2 beta 2 Platform: iOS 10

Running a simple, non-failable task with retry, retries even if the task finishes without error.

let inlineTask = InlineTask { (_) in
    print("inlineTask")
}.retry(2)

queue.add(task: inlineTask)

prints inlineTask 3 Times to the console, even if the documentation of retry states:

If the task finishes with error, it will be executed again until retry count becomes zero.

Overdrive: 0.2.2 Package manager (SPM, Carthage, CocoaPods, Manual): CocoaPods Xcode: 8.2.1 Platform: iOS 10

Tasks added to a TaskQueue being suspended don't run after setting isSuspended = false. Seems to be a Task specific issue because adding a BlockOperation to the TaskQueue's internal OperationQueue does not cause this issue. Please notice the attached sample code. ViewController.swift.zip

I encountered a problem when cancelling a task that's in pending state because it has a dependency on another task that's still running. As you just returned true for isReady property when in pending state start() is called on the cancelled task calling moveToFinishedState() leading to an illegal state transition from .pending to .finished. I solved this issue by setting the task's state to .ready as soon as super.isReady returns true.

Overdrive version: 0.2.0

Package manager: CocoaPods 1.1

This snippet

let queue = TaskQueue()
queue.maxConcurrentTaskCount = 3

throws 'maxConcurrentTaskCount' is inaccessible due to 'internal' protection level. See #2 for a possible fix.

Description: Since SynchronousTask implementation relies on result property being set to finish, not setting the result property would make the task execute forever.

Proposed fix: Add internal method to finish the task if the result is not set.

I encountered a problem when cancelling a task that's in pending state because it has a dependency on another task that's still running. As you just returned true for isReady property when in pending state start() is called on the cancelled task calling moveToFinishedState() leading to an illegal state transition from .pending to .finished. I solved this issue by setting the task's state to .ready as soon as super.isReady returns true. Added appropriate test.

I encountered a problem when cancelling a task that's in pending state because it has a dependency on another task that's still running. As you just returned true for isReady property when in pending state start() is called on the cancelled task calling moveToFinishedState() leading to an illegal state transition from .pending to .finished. I solved this issue by setting the task's state to .ready as soon as super.isReady returns true.

I encountered a problem when cancelling a task that's in pending state because it has a dependency on another task that's still running. As you just returned true for isReady property when in pending state start() is called on the cancelled task calling moveToFinishedState() leading to an illegal state transition from .pending to .finished. I solved this issue by setting the task's state to .ready as soon as super.isReady returns true.

Overdrive: 0.3 Package manager (SPM, Carthage, CocoaPods, Manual): n/a Xcode: 8.3.2 (macOS 10.12.5) Platform: iOS

When TaskQueue.maximumConcurrentTaskCount = 1`, only one task is executed. (The 2nd task is not executed.)

Here is a test case that indicates the issue.

    func testTwoTaskShouldBothCompleteWhenMaxConcurrentTaskCountIsOne() {

        queue.maxConcurrentTaskCount = 1

        let expectation1 = self.expectation(description: "a")
        let expectation2 = self.expectation(description: "b")

        let task = anyTask(withResult: .value(1))
        task.onValue { _ in
            expectation1.fulfill()
        }
        let task2 = anyTask(withResult: .value(1))
        task2.onValue { _ in
            expectation2.fulfill()
        }
        queue.add(task: task)
        queue.add(task: task2)

        waitForExpectations(timeout: 5)

    }

The test fails as the "b" expectation is unfulfilled. Any ideas what could be wrong?

Overdrive: 0.3 Package manager (SPM, Carthage, CocoaPods, Manual): CocoaPods Xcode: 9.0 beta 6 Platform: iOS

The dependency system seems to be failing in iOS 11. I have tried this with Xcode 9 betas 6 & 7 (latest right now). Quite a few tests are failing, especially an assertion failure TaskConditionTests, which seems to be the most severe, which actually is affecting our production users on iOS betas with crashes.