Data and file upload support

[tonyskansf]

This pull request introduces an upload feature allowing clients to upload data and files (no stream or multipart file support yet). The implementation follows the existing download feature design with slight deviation whilst aiming to keep consistency and familiarity with the API. With that, the changes also include an example that showcases the usage of the API.

Please, do not consider this implementation as final but rather as the first draft.

Video

Simulator.Screen.Recording.-.iPhone.14.Pro.-.2023-06-13.at.17.24.34.mp4

Implementation

UploadTask

The central component is the UploadTask object that encapsulates the ongoing URLSessionUploadTask and provides the task's state updates. Each upload request creates an upload task instance that is internally stored until the request is completed. In case of a failed request, the UploadTask serves as the representation of the failed request and is important in subsequent retry attempts.

UploadTask.State

This object represents the progress of the upload request and is updated continuously by the internal publisher. It is then available to the client as an asynchronous sequence. Since the implementation creates the URLSessionUploadTask with completion handlers, the response is accessible only upon the task's completion. Consequently, the response or error is delivered within the upload task's state.

Retryable

The UploadTask conforms to the Retryable protocol instead of the UploadAPIManager as is in the DownloadAPIManager. This emphasizes the intention that the task itself is retryable, rather than the manager. Despite potentially deviating from the original design of the protocol, this approach seems to work as well. Each upload task has its retryCounter: Counter that determines whether the task should be retried based on the RetryConfiguration.

Additional Notes

• The sample does not include a complete router example intentionally. I've used this service for testing purposes.

[gajddo00]

@cejanen What I mean was just different approaches to the same thing which is absolutely fine, but most of the functionality is the same so I was thinking whether it would be feasible to have one generic solution for both that could be inherited from or something in that sense.
Because the differences come down to

• urlSession.download vs urlSession.upload
• UrlSessionDownloadTask vs URLSessionUploadTask
• different progress state object emitted in the stream
  🤔 but I'm just thinking out loud here, maybe it wouldn't even be possible

[tonyskansf]

Some things (objects) could certainly be unified, but I'd rather not decide this as it changes the implementation of either of the managers.

[brenovaladao]

got an error when uploading a specific photo from the simulator

Error Domain=NSItemProviderErrorDomain Code=-1000 "Cannot load representation of type public.jpeg" UserInfo={NSLocalizedDescription=Cannot load representation of type public.jpeg, NSUnderlyingError=0x6000036ba9a0 {Error Domain=NSCocoaErrorDomain Code=4101 "Couldn’t communicate with a helper application." UserInfo={NSUnderlyingError=0x6000036bdda0 {Error Domain=PHAssetExportRequestErrorDomain Code=0 "The operation couldn’t be completed. (PHAssetExportRequestErrorDomain error 0.)" UserInfo={NSLocalizedDescription=The operation couldn’t be completed. (PHAssetExportRequestErrorDomain error 0.), NSUnderlyingError=0x6000036bf660 {Error Domain=PAMediaConversionServiceErrorDomain Code=2 "The operation couldn’t be completed. (PAMediaConversionServiceErrorDomain error 2.)" UserInfo=0x6000038e1820 (not displayed)}}}}}}

[gajddo00]

I also got this, but it's the simulator problem with corrupted images, nothing to do with uploading I think

[cejanen]

@tonyskansf I answered last comments or resolved issues, we're almost done 👍

[cejanen]

🥡