JSONEncoder/JSONDecoder and String convenience methods

[fabianfett]

Motivation:

Little common denominator after a long discussion in #129: JSONEncoder and JSONDecoder should have convenience methods to encode into String and decode from String.

Result:

• It's a little easier to deal with json payloads that are delivered in a String. (APIGateway, SNS, SQS)
• Public API is increasing

[Roshankumar350]

can be refactored as
public func encodeAsString<Element: Encodable>(_ value: Element) throws -> String

[Roshankumar350]

can be refactored as
public func decode<Element: Decodable>(_ type: Element.Type, from string: String) throws -> Element

[ktoso]

Mixed feelings about this one to be honest. One one hand that's harmless okey API and a nice quality of life change, but on the other adding much public convenience APIs on Foundation's coders is somewhat meh... I.e. not every library using JSONEncoders should invent many convenience APIs to them as we could end up with similar or same APIs defined in many libs etc...

Anyway, not a strong opinion

[ktoso]

I somewhat fail to see how this specific extensions are addressing the wider goal that was discussed in the linked issue #129 @fabianfett ? Tomer's comment #129 (comment) outlines a somewhat wider effort than just the string coding functions -- i.e. by adding functions to the gateway handler, rather than just to specific JSON coder types.

What am I missing here?

[ktoso]

Chatted some more; as I mentioned, not really strong opinion here so going to leave to @tomerd to decide if we're ok with these 👍

[tomerd]

my only concern here is with extending public types from the SDK from which may conflict with other libraries if they do the same - we typically try to avoid doing so

@weissi wdyt?

[fabianfett]

my only concern here is with extending public types from the SDK from which may conflict with other libraries if they do the same - we typically try to avoid doing so

I don't want to steer the discussion in one direction and I'm sure you're aware, but let me mention for completeness, that we also extend the JSONEncoder and JSONDecoder for ByteBuffer.