Another update. I figured out how to get the encoders and decoders out of the ports using a native module. So I no longer have to actually send things across ports (still have to declare them). I can also now use Elm's Http module.
Here's a gist of what it takes: https://gist.github.com/kspeakman/3f9521b0921b352c7d656261ec0a8fa6 On Saturday, February 18, 2017 at 2:22:32 AM UTC-6, Kasey Speakman wrote: > > An update. I'm using the ports approach to deal with JSON (and also > sending the HTTP request). For several months, I've had a small but > critical app in production using that. Another project in development is > too. In the process, I have run across two additional caveats with this > approach. > > 1. *Ports don't convert undefined properties to Maybe.Nothing.* It's > an open issue from Jan 2016. > <https://github.com/elm-lang/core/issues/476> > For a Maybe property, the JSON must have the property present and set > to null. Otherwise error. This is particularly annoying when you store the > data as JSON and pass it back to the client as-is. To work around this > issue, I either have to waste space storing nulls in the database or waste > (CPU/response) time server-side to inject nulls in the response. > > 2. *Cmd.map can't be used with this method.* > Using Http module, you can use Cmd.map to take some data from the > request and give it to the response Msg. Using ports, you can't do that. > I've noticed this when the data is easy to provide for a request, but > after > the response comes back it is less convenient to dig out of the model > (e.g. > behind a case statement). > > Neither of these are blockers for me, just nuisance issues. It still beats > maintaining codecs. > > I've seen rumblings about tools for code-gen'ing JSON codecs for us (maybe > elm-format? <https://github.com/avh4/elm-format/issues/194> There also > exists elm-swagger, but I don't use swagger.). I dunno though. Where > possible, I tend to avoid code-gen because it's for handling a really > tedious problem. And if the code-gen fails, then I have to handle a really > tedious problem. (XSD/WSDL flashbacks.) > > All it would really take for a profound QoL improvement are a couple of > "special" functions on Http that handle data exactly like ports do now... > just saying. > -- You received this message because you are subscribed to the Google Groups "Elm Discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
