LSL Protocol/Restrained Love Open Relay Group/http-in

!x-http

STATUS: in writing, DO NOT USE IT!

VERSION: 001

Draft1 implemented in Satomi's Multi-Relay HUD 1.00pre, and Satomi's Witchy Remote 1.2pre

Initiate an http-in encapsulated RLVR session.

On ok'ing an !x-http, the relay should make sure it has an LSL http server running, responding as described below. The command should be ignored (or ko'd) by older relays.

Other commands used in this protocol: !x-channel. Full support for !x-channel is also strongly recommended for !x-http support.

HTTP encapsulation

Assuming <relay_url> is the url of the relay, the relay controller will send encapsulate requests to the relay through HTTP by sending HTTP requests using method POST, with the following address: <relay_url>?<identifier>,<RLVR command>. Everything after "?" has to be escaped with llEscapeURL. The relay should of course decode the request with llUnescapeURL before handling the RLVR command.

The relay answers (llHTTPResponse, using the same key as the one in the previous http_request event) with a body constituted of lines that are:

• either a RLVR standard response (only without the recipient key): <identifier>,<RLVR command>,<ack> for a relay message.
• or a RL viewer answer (for instance an answer to a @getstatus or @version): <channel>,<viewer answer>

Protocol scenarii

Conventions: messages are symbolized by different types of arrows. We suppose the controller (C) is on the left and the relay (R) on the right. An arrow with a c (-c>) is a chat message on RLVR channel (or whatever channel the controller and the relay negotiated before). A right arrow with a h (-h>), is the message after the "?" in a the HTTP request URL from the controller. A left arrow with a h (<h-) is one line in the body of a reply from the relay to the controller HTTP request.

C(ontroller)<->R(elay)

HTTP session initiation protocol

This protocol establishes an authentified http session and transfers whatever restrictions C already had on R if any.

1 -c>     blah,k(R),!x-http
2 <c-     blah,k(C),!x-http,http://sim8867.agni.lindenlab.com:12046/cap/07307f17-dee4-bb85-04c7-340cdfade115/RLVR

Comments:

• After 2, the relay is ready to initiate the session (it is listening to http requests)

Relaying viewer chat messages:

( -h>  bloh,@getxxxx=1234
  <h-   bloh,@getxxx=1234,ok )
<h-    1234,<chat_message>

Ending HTTP session and going to chat

-h>     blih,!x-channel/-12345
<h-     blih,!x-channel/-12234,ok

Both relay and controller have to check that their recipient is in chat range. The controller before even trying. The relay before acknowledging. If the latter fails, then the relay should answer:

<h-     blih,!x-channel/-12234,ko

Testing controller's presence

For garbage collection purposes, be it on relog, or on regular basis, R might want to check if C is still active. The ping mechanism can be used here.

<h-    ping,ping,ping
-h>    ping,!pong

C can check R's presence by sending any valid message, as acknowledgement by R is required for every RLVR message from C. If the only purpose of the message is presience verification, the following scenario is recommended:

-h>    blah,!x-http
<h-    blah,!x-http,<anything>

Handover

!x-handover/K/n should work like in chat session.

Requirements

• On !x-http acknowledgement, the relay should start listening to http requests and handle them like RLVR messages.
• Whenever the relay accepts a RLV command with calls for a viewer answer (@blah=1234), the relay must listen to the viewer answer, and forward it via http response to the controller.