Hi Folks,

As you know we have a Java Sender Library that can be used by any backend application that want to send messages to the Unified Message Push Server (https://github.com/aerogear/aerogear-unified-push-java-client).

The format is quite open and flexible as Matthias described it here : https://gist.github.com/matzew/b21c1404cc093825f0fb

We can divide the creation of a message in 2 main parts :

- The "signalling" part : list of client identifiers / specific devices etc ...

- The "core" message containing actually the information we want to push

Both are passed as Map and are finally converted into JSON.

Here an example of how a "core" message is build :

Map categories = new HashMap();
categories.put("lead", "version="+leadVersion++); 
Map json = new HashMap();
json.put("id", lead.getId());
json.put("messageType", "pushed_lead");
json.put("name", lead.getName());
json.put("location", lead.getLocation());
json.put("phone", lead.getPhoneNumber());
json.put("simple-push", categories);
json.put("sound" ,"default");
json.put("alert" ,"A new lead has been created");

Even the format is open, we could "assist" a bit the developer in building the message. For that we have different options :

- Propose a simple Message object containing the message "API" :

Message message = new Message();
message.setClientIdentifiers("jake","maria");
message.enableSound();//by default use "default" or we could do message.enableSound("boing")
message.setAlert("Watch out!);
message.setAttribute("customAttribute","yo"); // custom simple strings
message.setAttribute("customStructure",myObject); // passing objects

- Propose a Message Builder (following the Builder Pattern) to propose a more fluent API :

Message message = new Message().builder()
  .clientIdentifiers("jake","maria")
  .enableSound()
  .alert("AAAAHHH!")
  .attribute("customAttribute","yo")
  .attribute("customStructure",myObject)
  .build()

- Same as above but more DSL focused (not sure about this one ;) )

Message message = MessageDSL.to("jake","maria").withSound() //etc ...

So, beside that we have to discuss what we want allow to pass to the message API : only Strings and simple Maps ? Full Objects that will be JSONified ?

Do we want also to separate the "signalling" part from the "core" part when building a message ?

Inputs and comments more than welcome !

Seb