feat: Upgrade Starscream to 4.0.4

[palpatim]

Issue #, if available: https://github.com/aws-amplify/aws-appsync-realtime-client-ios/issues/44

Description of changes:

This is a POC for upgrading Starscream to 4.0.4. It resolves API compatibilities between Starscream 3.x and 4.x, and all integ & unit tests pass. However, I have not yet run AppSync or Amplify tests using this as a base, so we'll need to do that before merging this.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[smhk]

cheers @palpatim just wondering about this, it's been a couple months, will it go ahead? cheers

[BhaveshTiwari]

@palpatim usually how long it will take to merge changes. We aren't able to use amplify because of this issue, as some other SPM are using latest version of Starscream

[lbasov]

@palpatim
Hi! Is there any updates on this PR? We are looking forward to use updated Starscream version and get rid of ignoring declared target(s) 'swift-nio-zlib-support' in the system package warning that come with 3.x starscream version.

[lawmicha]

I was thinking about whether we should use native websockets along with starscream, but I can see in the Starscream code it uses native when iOS 13 and up which is what we want

public convenience init(request: URLRequest, certPinner: CertificatePinning? = FoundationSecurity(), compressionHandler: CompressionHandler? = nil, useCustomEngine: Bool = true) {
        if #available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *), !useCustomEngine {
            self.init(request: request, engine: NativeEngine())
        } else if #available(macOS 10.14, iOS 12.0, watchOS 5.0, tvOS 12.0, *) {
            self.init(request: request, engine: WSEngine(transport: TCPTransport(), certPinner: certPinner, compressionHandler: compressionHandler))
        } else {
            self.init(request: request, engine: WSEngine(transport: FoundationTransport(), certPinner: certPinner, compressionHandler: compressionHandler))
        }
    }

[lawmicha]

this has been released in https://github.com/aws-amplify/aws-appsync-realtime-client-ios/releases/tag/1.7.0 it upgrades to 4.0.4 of Starscream, please let us know if you have any issues with this!

[smhk]

finally! :) TY