接受多个输入并以相同方式处理它们的最佳实践

Question

I am building an application that will be accepting requests from different clients and sending them to a single output. These clients will be sending different JSON requests that ultimately need to be transformed and then submitted to a final service. An example of what I mean..

ClientA posts ObjectA as JSON to endpoint /clientA. This request is transformed into an object FinalObject and submitted to a work queue via ServiceA that is processed and sent to FinalEndpoint.

ClientB posts ObjectB as JSON to endpoint /clientB. This request is transformed into an object FinalObject and submitted to a work queue via ServiceA that is processed and sent to FinalEndpoint.

I would like to avoid duplicating the code as much as possible. I'm really not sure what the best way to do this is. The fields in ObjectA and ObjectB are completely different and need to be formatted and calculated to derive FinalObject. I imagine I'll need some kind of Transformer to convert to the appropriate object I'm just not sure what pattern to use.

Any help is GREATLY appreciated. Thank you.

Answer 1

The most general solution: you define endpoint (if you are using springMVC it can be /process/${eventType}/) that accept some json body. Based on eventType (it can be part of url or urlParam) you decide what convertor to use for json.

Map<String, JsonConvertor> converters = new HashMap<>();
//init convertos map with possible cases you want to handle

//in controller method
outputResult = converters.get(eventType).convert(inputJson)
sendResult(ouputResult)

Answer 2

I would create a common Interface that is implemented by objectA and ObjectB, the interface could contain both objectA and objectB fields, let the interface be ObjectX, each implementation could contain the transformation method that returns a FinalObject and do the transformation differently for ObjectA and ObjectB, this is an example:

1- FinalObject class

public class FinalObject {
   // FinalObject implementation here 
}

2- Interface

interface ObjectX {
    public FinalObject getFinalObject();
  // define any other common methods that you might need for both objects
}

3- ObjectA

public class ObjectA implements ObjectX {
    // define any special fields
    @override
    public FinalObject getFinalObject(){
         // implement conversion of ObjectA to FinalObject here 
    }
// implement any other methods you need 
}

4- ObjectB

 public class ObjectB implements ObjectX {
    // define any special fields
    @override
    public FinalObject getFinalObject(){
         // implement conversion of ObjectB to FinalObject here 
    }
// implement any other methods you need 
}

and for the service it could be a single service distinguish which implementation to use depending on the JSON values, or you can use different paths/parameters for each client to access a different method on your service controller. I hope that this is the answer you are looking for.