RetrofitRxErrorHandler

What is it?

RetrofitRxErrorHandler is an attempt to harden Retrofit HTTP API layer against random errors, like timeouts, 500 server errors caused due to server overload or accidental loss of networks (happening especially in mobile applications).

Who should use it?

Everyone who is using Retrofit combined with RxJava and experienced random errors when sending requests.

Usage

1. Import gradle dependency:

   • Add following lines to you project's main build.gradle:

       buildscript {
           repositories {
               jcenter()
           }
       }
     

   • Add a dependency to application build.gradle:

       compile 'com.rzagorski:retrofitrxerrorhandler:1.1.0'
     

2. Build the strategy:

     RxCallAdapter rxCallAdapter = new RxCallAdapter.Builder()
                 .addBackoffStrategy(Exponential.init()
                         .addThrowable(HttpException.class)
                         .setMaxRetries(3).build())
                 .build();
   

3. Add it as Retrofit CallAdapter.Factory:

     Retrofit retrofit = new Retrofit.Builder()
         .addCallAdapterFactory(new RxErrorHandingFactory(rxCallAdapter))
         .build()
   

Options:

• different backoff strategies (Simple, Exponential)

     Simple.init().(...).build()
  

  or

     Exponential.init().(...).build()
  

Common:

• reactions to different Throwables

     Exponential.init()
         .addThrowable(HttpException.class)
  

• reactions to HTTP error codes

     Exponential.init()
         .setResponseCode(500)
  

• exclusive or inclusive behaviour to Throwables or HTTP error codes

     Exponential.init()
         .exclusive()
  

• maximum retry count (different for every added strategy)

     Exponential.init()
         .addThrowable(HttpException.class)
         .setBase(2)
         .setMaxRetries(3)
  

• backup Observable (executed before strategy delay and after every occurrence of error or HTTP response code)

     Exponential.init()
         .addObservable(backupObservable)
  

Exponential:

• base of exponential function:

      Exponential.init()
          (...)
          .setBase(2)
  

Examples

Look into tests

License

Copyright 2016 Robert Zagórski.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.