Revision as of 07:35, 6 July 2009

Basic Communication

For every string message that is to be sent between a module and server, the sender first sends the length of the message ENCODED_MESSAGE_LENGTH and then the message MESSAGE. The max length FRAG_SIZE of a message to be sent is 65536 bytes. If a message is longer, it is divided into fragments. ENCODED_MESSAGE_LENGTH is called ENCODED_ because it also contains a FRAG_FLAG which specifies if the next message is a fragment and has to be assembled to a whole message after receiving.

Let's say the server wants so send a message of size 150'000 bytes to the module. The following would be sent: [65536 FRAG_FLAG=1][Message part 1...][65536 FRAG_FLAG=1][Message part 2....][18928 FRAG_FLAG=0][Message part 3....]

The ENCODED_MESSAGE_LENGTH is constructed as follows: The lenght of the message (integer) is shifted by 1 bit to the left. Then the most right bit is set to FRAG_FLAG.

Request Message

For every request, the module sends a message of the following format to the server:

REQUEST = GET_REQUEST | POST_TABLE_REQUEST | POST_PLAIN_REQUEST;
 
GET_REQUEST = KEY_GET BODY TABLE_ARGS;
POST_TABLE_REQUEST = KEY_POST HEADER HEADERS_IN_WITH_CT HEADERS_OUT SUBPROCESS_ENVIRONMENT_VARS TABLE_ARGS;
POST_PLAIN_REQUEST = KEY_POST BODY PLAIN_ARGS;
 
BODY = HEADER HEADERS_IN HEADERS_OUT SUBPROCESS_ENVIRONMENT_VARS;
HEADER =  KEY_SPACE  url KEY_SPACE KEY_HTTP;
 
HEADERS_IN = KEY_HI {TABLE_ENTRIES}  KEY_END;
HEADERS_IN_WITH_CT = KEY_HI {TABLE_ENTRIES} KEY_T_NAME KEY_CT KEY_T_VALUE KEY_CT_FORM {TABLE_ENTRIES} KEY_END;
HEADERS_OUT = KEY_HO {TABLE_ENTRIES} KEY_END;
SUBPROCESS_ENVIRONMENT_VARS = KEY_SE TABLE_ENTRIES KEY_END;
TABLE_ENTRY = KEY_T_NAME item_name KEY_T_VALUE item_value;
 
TABLE_ARGS = KEY_ARG  {KEY_A_NAME arg_name KEY_A_VALUE arg_value}  KEY_END;
PLAIN_ARGS = KEY_ARG KEY_A_NAME post_arg_text KEY_END;
 
 
KEY_GET = "GET";
KEY_POST = "POST";
KEY_HTTP = "HTTP/1.1";
KEY_SPACE = " ";
KEY_HI = "#HI#";
KEY_HO = "#HO#";
KEY_END = "#E#";
KEY_SE = "#SE#";
KEY_T_NAME = "#$#";
KEY_T_VALUE = "#%#";
KEY_ARG = "#A#";
KEY_A_NAME = "$";
KEY_A_VALUE = "=";
KEY_CT = "Content-Type";
KEY_CT_FORM = "application/x-www-form-urlencoded";

Example

GET /demoapplication/reservations.xeb HTTP/1.1#HI##$#Host#%#localhost:55000#$#User-Agent#%#Mozilla/5.0 (X11; U; Linux x86_64; en; rv:1.9.0.11) Gecko/20080528 Epiphany/2.22 Firefox/3.0#$#Accept#%#text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8#$#Accept-Language#%#en-us,en;q=0.5#$#Accept-Encoding#%#gzip,deflate#$#Accept-Charset#%#ISO-8859-1,utf-8;q=0.7,*;q=0.7#$#Keep-Alive#%#300#$#Connection#%#keep-alive#$#Referer#%#http://localhost:55000/demoapplication/contact.xeb#$#Cookie#%#xuuid=E5573216-8AEC-4187-8ECD-0BC38CF36FF0#E##HO##E##SE##E##A##E#

Response Message

The server answers with a response message of the following format:

RESPONSE = {COOKIE_ORDER} CONTENT_TYPE HTML;
COOKIE_ORDER = "#C#" cookie_name "=" cookie_value COOKIE_OPT ";Version=1#CE#";
COOKIE_OPT = [";" "Domain=" cookie_domain]
             [";" "Max-Age=" cookie_max_age]  
             [";" "Path=" cookie_path]
             [";" "Secure"];
CONTENT_TYPE = "#CT#" content_type;
HTML = "#H#" html_code;

Example