HTML VECTOR CODE CODE

But at the time, browsers had not yet been developed to a point that was suitable for the new SVG format in the case of the Internet Explorer, external plugins such as the Adobe SVG Viewer and the Batik SVG Toolkit from Apache were mandatory in order to read and display XML graphics for a long time. The meanings of the fields can be found in RFC6455.When W3C scalable vector graphics became the recommended specification for two-dimensional vector graphics in 2001, the XML language was considered an optimal solution for the representation of such graphics, both in static and animated forms. The following picture shows a structure of a websocket data frame. Each message consists of a number of frames. The data exchange between a websocket client and server is done by means of messages. Coming back to our chat application, below is a state diagram of the chat session. Once the HTTP response is sent to the client, the handshake phase considered as complete and we can start data exchange. Std::string accept(to_base64(to_sha1(buffer))) Void request_handler::handle_request( const request& req, reply& rep)įor ( std::vector ::const_iterator h = ()

HTML VECTOR CODE CODE

The following code illustrates the handshake procedure.

Send the base64 equivalent of the hash in HTTP response to the client.

Take the SHA1 hash of the concatenation result.

Concatenate the handshake key with the magic guid.According to the WebSocket protocol, the server should:

Among those headers there is the Sec-WebSocket-Key header, which contains a handshake key. In order to establish a websocket connection, a client (a web browser) sends a HTTP GET request with a number of HTTP headers. The client code is based on the example from the server code is based on the boost.asio example, where is your code, one may ask? Here you are! A basic implementation of the WebSocket protocol.Ī websocket session consists of two consecutive phases: a handshake and data exchange. When a message from the client arrives it is being delivered to all the room participants. Each chat_session object contains a socket to interact with the client.When a client connects to the server, the server creates a chat_session object and adds the object to the room.The server contains a room object, which is a container for chat participants.The server works with sockets in an asynchronous manner, using I/O completion ports, and can easily be extended to run two or more threads.īelow is a class diagram for the chat application. The server’s code is based on the Chat application example from the boost.asio library, credits to Christopher M. To send a message to the server the send function is used: a message with a number of connected chat participants, the ' connected:' message.īased on a message type we show its content in a corresponding web page element.a chat participant message itself, the ' log:' message,.

Note, there are two types of messages the server sends to the client: State.innerHTML = ' Communication error' Message = message.slice( ' connected:'.length) Log.innerHTML = ' ' + message + ' ' + log.innerHTML Įlse if (message.startsWith( ' connected:')) Message = message.slice( ' log:'.length) a message with a number of connected chat participants. There are two types of messages: // 1. State.innerHTML = ' Connected to server' To connect to a server we need to call the websocket constructor with the following string as a parameter: The client is implemented as a web page, which creates a websocket object and subscribes to its events: open, close, error and message. The client’s code is based on a simple chat client example from credits to Remy Sharp. The server-side socket support is implemented using the boost.asio library, the server’s code pretends to be a cross-platform one. At the moment the most complete support of RFC6455 is implemented by Mozila Firefox (15.0), Google Chrome (.89) and Internet Explorer 10 (.0) web browsers, they were used to test the application. This task will be accomplished by using a new HTML5 feature called WebSocket, which is described in RFC6455. The client/server application implies sending data between participants. The client is implemented using HTML5, the server is implemented in C++. In this article I would like to show a basic implementation of HTML5 client/server application.

Html vector code