What do you think about Codable of Swift 4?

[jassadakorn]

We don't need to use objectMapper anymore

[dcortes22]

@jassadakorn why not?

[jassadakorn]

@dcortes22 Because objectMapper have to check Json key for each property in mapping function but Codable don't have to check ( See also ) . It's mean the key can be invalid by human error if we use objectMapper

[dcortes22]

Very interesting thanks for the clarification!

[shiyizju]

With Codable, I guess the variable's name must be same as json key, and every variable will be coded into json?

[devxoul]

ObjectMapper still provides more detailed functionality.

[skydivedan]

With Codable, the property name does not need to be the same as the JSON key, you can easily map to a different name.

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This does change things for me, though. I pour JSON into Realm objects. The main reason I use ObjectMapper is for mapping ISO8601 Strings into Date objects, since Realm has no mechanism to do this. I don't know what the folks at Realm think about Codable, (and I haven't thought this through yet myself!), but if Codable could be adopted in Realm, then all those DateTransforms could drop away... which might mean that I could drop ObjectMapper.

I don't know if this is truly feasible, but something to think about.

[yariksmirnov]

I use ObjectMapper in cause of really useful support of custom transformations. In case of Realm I created my custom transformers to create-or-update objects which are referenced by ids in REST APIs.

[loudmouth]

I think the nested keypath options of ObjectMapper provide functionality that make it more adaptable to a wide variety of JSON API's. Being able to do things things like:

contentTypeId   <- map["contentType.sys.id"]

Rather than having additional nested structs is a big advantage of ObjectMapper for interfacing with certain APIs.

[aksswami]

But the same can be achieved via Codable and as this is the language feature, so it will be more widely used and also we will have consistent parsing across most of the projects.

[pmusolino]

Codable has the .toJSON() feature?

[aksswami]

Yes, Codable have Encoder and Decoder which we can use for toJSON and fromJSON.

[pmusolino]

OK, but the encoder is automatic like ObjectMapper, or you have to explicit how to encode the variables?

[loudmouth]

@Codeido here is the WWDC video describing "What's New in Swift"

[jonasman]

Im also planning to replace ObjectMapper in all my projects (even professional ones) with Swift4's Codable.

[emoryalimam]

here’s a great guide on using Codable in Swift 4: http://swiftjson.guide

[aksswami]

The best guide for Codable I came across:- http://benscheirman.com/2017/06/ultimate-guide-to-json-parsing-with-swift-4/

[jonasman]

I tried to convert from ObjectMapper to Codable and i must it is such a pain... OM is superior.

[guitcastro]

@jonasman Can you please elaborate why?

[tomaskraina]

For anyone still interested in the pros and cons between decodable vs ObjectMapper, I've found a nice writeup: https://medium.com/bbc-design-engineering/codable-vs-objectmapper-af5fe8e8efd5