Service classes should define the in/out mapper methods themselves

[jurajpiar]

Mappers should be defined in the service class and be called via the abstract api class. This would allow:

1. less code duplication in _fetch methods
2. easier and clearer testing
3. better debugging
4. de-coupling of fetch and mapping

Example:

class AbstractApiService {
   _fetch = (args) => {
     const options = this.mapForTransport(args)
     const result = this.fetch(options)
     const { data, ...metadata } = isResultPaginated(result) ? result : { data: result }
     this.meta = metadata
     const mapped = this.mapFromTransport(data)
     
     return data
  }
}

class ExampleService extends AbstractApiService {
    _fetch = () => this.service.find()
}