Anonymous and Apple Login

[cbaker6]

This PR adds 3rd party login ability via the ParseAuthenticatable protocol.

• Add ParseAnonymous and ParseApple login
• Add ParseAuthenticatable protocol for implementation by developers. Example: Facebook, Twitter, etc. should conform to protocol and PR's can be submitted to add them. The dependency of the the respective framework, i.e. import FBSDKCoreKit shouldn't be part of the PR (this should be done by the developer in their respective apps). Instead the implementation should just ensure the necessary AuthenticationKeys are captured to properly authenticate the respective framework with a Parse Server. An example of this is ParseApple.swift. As a starting point for those who want to add more 3rd party methods, I recommend copying ParseApple.swift and modifying AuthenticationKeys and helper methods. All of the Parse server-side 3rd party supported authentication methods are here along with their respective documentation.
• Add ParseSession protocol
• Add documentation
• Add test cases
• Add playground examples

Usage (same can be done for "apple", just need to pass in apple credentials to login):

// Anonymous asynchronous login

//Assuming you define the ParseUser
struct User: ParseUser {
    //: These are required for ParseObject
    var objectId: String?
    var createdAt: Date?
    var updatedAt: Date?
    var ACL: ParseACL?

    //: These are required for ParseUser
    var username: String?
    var email: String?
    var password: String?
    var authData: [String: [String: String]?]?

    //: Your custom keys
    var customKey: String?
}

// You can log the User in using:
User.anonymous.login { result in
    switch result {
    case .success:
        print("Successfully logged in \(User.current)")
    case .failure(let error):
        print("Error logging in: \(error)")
    }
}

[codecov]

Codecov Report

Merging #53 (5e8ac47) into main (84f9231) will increase coverage by 0.06%.
The diff coverage is 77.00%.

@@            Coverage Diff             @@
##             main      #53      +/-   ##
==========================================
+ Coverage   76.22%   76.28%   +0.06%     
==========================================
  Files          42       46       +4     
  Lines        3886     4170     +284     
==========================================
+ Hits         2962     3181     +219     
- Misses        924      989      +65     

Impacted Files	Coverage Δ
Sources/ParseSwift/API/Responses.swift	67.39% <ø> (ø)
Sources/ParseSwift/Internal/ParseHash.swift	94.11% <ø> (ø)
Sources/ParseSwift/Storage/KeychainStore.swift	97.75% <ø> (ø)
Sources/ParseSwift/Objects/ParseUser.swift	74.77% <70.40%> (-0.91%)	⬇️
...uthentication/Protocols/ParseAuthenticatable.swift	72.63% <72.63%> (ø)
...rseSwift/Authentication/3rd Party/ParseApple.swift	78.84% <78.84%> (ø)
...Swift/Authentication/Internal/ParseAnonymous.swift	86.95% <86.95%> (ø)
Sources/ParseSwift/Objects/ParseInstallation.swift	82.18% <100.00%> (+0.57%)	⬆️
Sources/ParseSwift/Objects/ParseSession.swift	100.00% <100.00%> (ø)
Sources/ParseSwift/Protocols/Objectable.swift	83.33% <100.00%> (+2.56%)	⬆️
... and 6 more

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[cbaker6]

@TomWFox can you look over the docs when you get a chance? I'm pretty much done with them and I don't think I need to a add anymore methods to the login protocols

[cbaker6]

@TomWFox we should probably add an improved version of my second bullet point above to the contributors guide (and maybe a snippet to the readme?):

Add ParseAuthenticatable protocol for implementation by developers. Example: Facebook, Twitter, etc. should conform to protocol and PR's can be submitted to add them. The dependency of the the respective framework, i.e. import FBSDKCoreKit shouldn't be part of the PR (this should be done by the developer in their respective apps). Instead the implementation should just ensure the necessary AuthenticationKeys are captured to properly authenticate the respective framework with a Parse Server. An example of this is ParseApple.swift. As a starting point for those who want to add more 3rd party methods, I recommend copying ParseApple.swift and modifying AuthenticationKeys and helper methods. All of the Parse server-side 3rd party supported authentication methods are here along with their respective documentation.

I can see a few questions/issues occurring frequently:

1. Can support be added for a "specific" authentication type? (Yes, following the directions above, developers are encouraged to submit PR's and have a blueprint on how to make a new one).
2. This is different from the objc-c SDK, can we get PFFacebookUtils and PFFacebookUtils? (Not exactly, the dependency won't be added, but developers are encouraged to create and conform to ParseAuthenticatable

I think the method above we have setup for adding support for basically any authentication the server supports leads to easier maintainability. Plus, this allows users the flexibility of using any version of their authentication framework they want, they simply just need to provide the minimum keys.

[TomWFox]

Mostly minor changes with one potential issue.

Getting closer to 1.0!

[TomWFox]

I think this could be an issue, see parse-community/parse-server#6612

[cbaker6]

I see, I think making it "optional" should make it backwards/forwards compatible with Parse Server. What do you think?

[cbaker6]

I can also remove it, developers just won't be able to see it in their Swift apps because it's never decoded

[cbaker6]

The only potential problem I see with removing is it will show in their Parse Dashboard, but not on their swift apps...

[TomWFox]

Making it optional seems like an acceptable option. I wonder whether the comment should be changed to say that the feature isn't implemented server side and/or link to the #6612

[cbaker6]

Guessing at the issue with jazzy docs.

I believe GitHub Actions may have recently bumped the default Xcode to 12.3 and I "think" jazzy and it's dependencies aren't playing nice. It looks like the docs are building fine with 12.2, so docs can stay on that version for now, while the rest of the builds continue on the latest Xcode.

[TomWFox]

@TomWFox we should probably add an improved version of my second bullet point above to the contributors guide (and maybe a snippet to the readme?):

I think adding to the contributors guide would be a good idea, not sure about the readme.