Custom date coding for URLEncodedForm

[tonyarnold]

I had a use-case today where my front-end HTML form was posting a UNIX timestamp to a Vapor route where I wanted to decode that value to a Date.

Unfortunately, it seems like URLEncodedFormDecoder is utilising Date(timeIntervalSinceReferenceDate:) rather than the correct (in this instance) Date(timeIntervalSince1970:), so all of my decoded dates were about 30 years off.

Steps to reproduce

1. Create a simple model with a Date property:

   struct MyModel: Content {
         let expiryDate: Date
   }

2. Create a that accepts this model via a post (router.post(MyModel.self, at: …))
3. Create a simple HTML form that posts to this route with a single value: expiryDate
4. Submit a UNIX timestamp via this form, and observe the date that gets decoded onto the model instance in your route handler.

Expected behavior

The date is decoded as a common UNIX epoch timestamp (00:00:00 UTC on 1 January 1970).

If this can't be determined automatically, then I'd expect to be able to override or customise this decoding much like we can with JSONDecoder.DataDecodingStrategy.

Actual behavior

The date is decoded using Foundation's reference date (00:00:00 UTC on 1 January 2001).

Environment

• Vapor Framework version: 3.3.1
• Vapor Toolbox version: 3.1.10
• OS version: macOS 10.15.2

[tanner0101]

Related to #2273

[thecheatah]

The documentation for pull #2273 is here #2272

[Joannis]

Closing this due to a fix having been merged.