update documentation

[src/app-framework-binder.git] / doc / afb-application-writing.md

diff --git a/doc/afb-application-writing.md b/doc/afb-application-writing.md
index a7099a8..70dde78 100644 (file)
--- a/doc/afb-application-writing.md
+++ b/doc/afb-application-writing.md
@@ -1,14 +1,45 @@
 HOWTO WRITE an APPLICATION above AGL FRAMEWORK
 ==============================================
     version: 1
 HOWTO WRITE an APPLICATION above AGL FRAMEWORK
 ==============================================
     version: 1

-    Date:    29 mai 2016
+    Date:    30 mai 2016

     Author:  José Bollo
 
 TABLE-OF-CONTENT-HERE
 
     Author:  José Bollo
 
 TABLE-OF-CONTENT-HERE
 

+Languages for writing Applications
+----------------------------------

 
 

-Writing a C application
------------------------
+### Writing an HTML5 application
+
+Developpers of HTML5 applications (client side) can easyly create
+applications for AGL framework using their prefered
+HTML framework.
+
+Developpers can also create powerful server side plugins to improve
+their application. This server side plugin should return the mime-type
+application/json and can be accessed either by HTTP or by Websockets.
+
+In a near future, the JSON-RPC protocol will be available together
+with the current x-afb-json1 protocol.
+
+Two examples of HTML5 applications are given:
+
+- [afb-client](https://github.com/iotbzh/afb-client) a simple "hello world" application
+
+- [afm-client](https://github.com/iotbzh/afm-client) a simple "Home screen" application
+
+### Writing a Qt application
+
+Writing Qt applications is also possible because Qt offers APIs to
+make HTTP queries and to connect using WebSockets.
+
+It is even possible to write a QML application.
+It is demontrated by the sample application token-websock:
+
+- [token-websock](https://github.com/iotbzh/afb-daemon/blob/master/test/token-websock.qml) 
+a simple "hello world" application in QML
+
+### Writing a C application

 
 C applications can use the binder afb-daemon through a websocket connection.
 
 
 C applications can use the binder afb-daemon through a websocket connection.
 


@@ -24,4 +55,39 @@ The current implementation use libsystemd and file descriptors.
 This may be changed in the future to also support secure sockets
 and being less dependant of libsystemd.
 
 This may be changed in the future to also support secure sockets
 and being less dependant of libsystemd.
 

+Handling sessions within applications
+-------------------------------------
+
+Applications must be aware of the the features session and token
+when they interact with the binder afb-daemon.
+
+Applications are communicating with their binder afb-daemon using
+a network connection or a kind of network connection (unix domain
+socket isn't currently implemented but could be used in near future).
+Also, HTTP protocol is not a connected protocol. It means that
+the socket connection can not be used to authenticate a client.
+
+For this reason, the binder should authenticate the application
+by using a commonly shared secret named token and the identification
+of the client named session.
+
+### Handling sessions
+
+Plugins and features of the binder need to keep track of the client
+instances. This of importance for plugins running as service
+because they may have to separate the data of each client.
+
+For common HTML5 browser running an HTML5 application.
+
+### Exchanging tokens
+
+At start, the framework communicates a common secret to both the binder
+and its client: the application. This initial secret is the
+initial token.
+
+For each of its client application, the binder manages a current active
+token. The initial token is the default active token. It is the expected
+token for new clients.
+
+