Difference between revisions of "LSL HTTP server/examples"

Latest revision as of 10:02, 29 April 2019

LSL Portal

Utility Script

A script intended as a 'fill in the blank' exercise for very, very simple HTTP servers is here: Utility Script

Hello World!

Classic example, the smallest http_request script possible.

default
{
    state_entry()
    {
        llRequestURL();
    }

    http_request(key id, string method, string body)
    {
        if (method == URL_REQUEST_GRANTED)
        {
            llSay(0,"URL: " + body);
        }
        else if (method == "GET")
        {
            llHTTPResponse(id,200,"Hello World!");
        }
    }
}

A slightly more robust version:

default
{
    state_entry()
    {
        llRequestURL();
    }

    http_request(key id, string method, string body)
    {
        if (method == URL_REQUEST_GRANTED)
        {
            llSay(0,"URL: " + body);
        }
        else if (method == URL_REQUEST_DENIED)
        {
            llSay(0, "Something went wrong, no url. " + body);
        }
        else if (method == "GET")
        {
            llHTTPResponse(id,200,"Hello World!");
        }
        else
        {
            llHTTPResponse(id,405,"Unsupported Method");
        }
    }
}

Echo World

"Echo World (Byrd Sciavo 04:19, 7 October 2009 (UTC))" is a slightly more useful "Hello World", demonstrating a basic server that echos back dynamic data fed. Echo World shows how http_request receives GET variables. To receive this "dynamic echo", append your cap url with a query string, such as https://sim3015.aditi.lindenlab.com:12043/cap/a7717681-2c04-e4ac-35e3-1f01c9861322/foo/bar?arg=gra

string url;
default
{
    state_entry()
    {
        llRequestURL();
    }

    http_request(key id, string method, string body)
    {    
        if (method == URL_REQUEST_GRANTED) 
        {
            url=body;
            llOwnerSay(url);
        }
        else if(method=="GET")
        {
              if(llGetHTTPHeader(id,"x-query-string")=="") 
                  llHTTPResponse(id,200,"I ECHO when you append some GET variables to me, e.g., /?var=foo");
              else 
                  llHTTPResponse(id,200,llGetHTTPHeader(id,"x-query-string"));
        }        
    }
}

HTTP Server URL Registration

HTTP Server URL Registration shows how to obtain the URL for your HTTP service and register it externally, and how to do proper backoff and retry as an HTTP Client.

Visitor List

A list of residents within sensor range of the server.
Notes:

This includes a method for handling multiple requests while waiting for asynchronous data requests to come back.

integer scanning = FALSE;

list requests;

send_response(string body)
{
    integer j;
    for (j = 0; j < llGetListLength(requests); ++j)
    {
        llHTTPResponse(llList2Key(requests,j), 200, body);
    }
    requests = [];
}

default
{
    state_entry()
    {
        llRequestURL();
    }
 
    http_request(key id, string method, string body)
    {
        if (method == URL_REQUEST_GRANTED)
        {
            llSay(0,"URL: " + body);
        }
        else if (method == URL_REQUEST_DENIED)
        {
            llSay(0, "Something went wrong, no url. " + body);
        }
        else if (method == "GET")
        {
            if (!scanning)
            {
                llSensor("",NULL_KEY,AGENT,96,PI);
                scanning = TRUE;
            }
            
            requests += [id];
        }
        else
        {
            llHTTPResponse(id,405,"Unsupported method.");
        }
    }
 
    no_sensor()
    {
        send_response("There is no one here.");
        scanning = FALSE;
    }
 
    sensor(integer n)
    {
        string output;
        if (n < 16) output = "There are " + (string)n + " avatars nearby:";
        else output = "There are at least 16 avatars nearby:";
        
        integer i;
        for (i = 0;i<n;++i)
        {
            output += "\n\t" + llDetectedName(i);
        }
        
        send_response(output);

        scanning = FALSE;
    }
}

Url Persistence / Visitor Counter

A more complete 'hello world', always has an url and keeps a visitor counter.

string url;
integer hits;

setup()
{
    llSetObjectName("HTTP Server");
    url = "";
    llRequestURL();
    hits = (integer)llGetObjectDesc();
    llSetText((string)hits + " visitors.",<1,1,0>,1);
}

default
{
    state_entry() { setup(); }
    on_rez(integer n) { setup(); }
    
    changed(integer c)
    {
        if (c & (CHANGED_REGION | CHANGED_REGION_START | CHANGED_TELEPORT) )
        {
            setup();
        }
    }
    
    touch_start(integer n)
    {
        llSay(0,"My url is: " + url);
    }
 
    http_request(key id, string method, string body)
    {
        if (method == URL_REQUEST_GRANTED)
        {
            url = body;
        }
        else if (method == URL_REQUEST_DENIED)
        {
            llSay(0, "Something went wrong, no url. " + body);
        }
        else if (method == "GET")
        {
            ++hits;
            llSetObjectDesc((string)hits);
            llSetText((string)hits + " visitors.",<1,1,0>,1);
            llHTTPResponse(id,200,"Hello!  You are visitor " + (string)hits + ".");
        }
        else
        {
            llHTTPResponse(id,405,"Method unsupported");
        }
    }
}

Perl/Python Examples Using POST

Here are a set of scripts to provide another example using POST. The first script is the LSL code to receive the information on the grid. The second script is a Perl script that is used on the outside server to contact the code on the grid. The third script is a Python script that is also used on the outside server to contact the code on the grid. (Grandma Bates 12:42, 27 May 2009 (UTC))

key requestURL;

default
{

    state_entry() 
    {
        requestURL = llRequestURL();     // Request that an URL be assigned to me.
    }
    
     http_request(key id, string method, string body) 
     {
        if ((method == URL_REQUEST_GRANTED) && (id == requestURL) )
        {
            // An URL has been assigned to me.
            llOwnerSay("Obtained URL: " + body);
            requestURL = NULL_KEY;
        }
        else if ((method == URL_REQUEST_DENIED) && (id == requestURL)) 
        {
            // I could not obtain a URL
            llOwnerSay("There was a problem, and an URL was not assigned: " + body);
            requestURL = NULL_KEY;
        }

        else if (method == "POST") 
        {
            // An incoming message was received.
            llOwnerSay("Received information from the outside: " + body);
            llHTTPResponse(id,200,"Thank you for calling. All of our operators are busy.");
        }
        else 
        {
            // An incoming message has come in using a method that has not been anticipated.
            llHTTPResponse(id,405,"Unsupported Method");
        }
    }
}

Here is the Perl script to contact the prim on the grid.

#!/usr/bin/perl
# Routine to contact a script on the SL Grid using http server
use strict;
use warnings;
use LWP;

my $browser = LWP::UserAgent->new;

sub submitInformation) {
    my( $url, $params ) = @_;
    return $browser->post( $url, $params )->content;
}

# Set the URL manually....
my $url = 'http://sim3015.aditi.lindenlab.com:12046/cap/d57a7c8b-3ace-3186-730a-f22fde870d48';

my $info = submitInformation( $url, {
    id   => '244195d6-c9b7-4fd6-9229-c3a8b2e60e81',
    name => 'M Linden',
} );

print $info,"\n";

Here is the Python code that does the same thing as the PERL code above.

#!/usr/bin/python

import urllib


# #################################################
# Routine to send the information to the prim
#     submitInformation(url,information)
#
def submitInformation(url,parameters) :
    # Set the parameters to be sent.
    encodedParams =  urllib.urlencode(parameters);

    # Post the data.
    net = urllib.urlopen(url,encodedParams);

    # return the result.
    return(net.read());



if __name__ == "__main__":

    # Set the URL manually
    url = 'http://sim3015.aditi.lindenlab.com:12046/cap/d57a7c8b-3ace-3186-730a-f22fde870d48';

    # Define the parameters
    parameters = {'id':'244195d6-c9b7-4fd6-9229-c3a8b2e60e81',
                  'name':'M Linden'}

    # Pass the information along to the prim
    info = submitInformation(url,parameters);
    print(info);

Perl/Python Examples Using POST With Argument Parsing

Here are a set of scripts to provide another example using POST. In this example the scripts are adapted to handle the parsing of the arguments that are passed. The first script is the LSL code to receive the information on the grid. The second script is a PERL script that is used on the outside server to contact the code on the grid. The third script is a Python script that is also used on the outside server to contact the code on the grid. (Grandma Bates 12:42, 27 May 2009 (UTC))

key requestURL;

// ###############################################
// Routine to parse a string sent through the 
// http server via post.
//       parsePostData(theMessage)
// Returns a strided list with stride length 2.
// Each set has the key and then its value.
list parsePostData(string message) {
    list postData = [];         // The list with the data that was passed in.
    list parsedMessage = llParseString2List(message,["&"],[]);    // The key/value pairs parsed into one list.
    integer len = ~llGetListLength(parsedMessage);

    while(++len) {          
        string currentField = llList2String(parsedMessage, len); // Current key/value pair as a string.

        integer split = llSubStringIndex(currentField,"=");     // Find the "=" sign
        if(split == -1) { // There is only one field in this part of the message.
            postData += [llUnescapeURL(currentField),""];  
        } else {
            postData += [llUnescapeURL(llDeleteSubString(currentField,split,-1)), llUnescapeURL(llDeleteSubString(currentField,0,split))];
        }
    }
    // Return the strided list.
    return postData ;
}

default {

    state_entry() {
        requestURL = llRequestURL(); // Request that an URL be assigned to me.
    }
    
    http_request(key id, string method, string body) {
         list incomingMessage;
        
        if ((method == URL_REQUEST_GRANTED) && (id == requestURL) ){
            // An URL has been assigned to me.
            llOwnerSay("Obtained URL: " + body);
            requestURL = NULL_KEY;
        }
        else if ((method == URL_REQUEST_DENIED) && (id == requestURL)) {
            // I could not obtain a URL
            llOwnerSay("There was a problem, and an URL was not assigned: " + 
                       body);
            requestURL = NULL_KEY;
        }
        else if (method == "POST") {
            // An incoming message was received.
            llOwnerSay("Received information form the outside: " + body);
            incomingMessage = parsePostData(body);
            llOwnerSay(llDumpList2String(incomingMessage,"\n"));

            llHTTPResponse(id,200,"You passed the following:\n" + 
                           llDumpList2String(incomingMessage,"\n"));

        }
        else {
            // An incoming message has come in using a method that has
            // not been anticipated.
            llHTTPResponse(id,405,"Unsupported Method");
        }
    }
}

Here is the coresponding PERL script for contacting the LSL script on the grid.

#!/usr/bin/perl
# Routine to contact a script on the SL Grid using http server
use strict;
use warnings;

use LWP;

my $browser = LWP::UserAgent->new;

sub submitInformation) {
    my( $url, $params ) = @_;
    return $browser->post( $url, $params )->content;
}

# Set the URL manually....
my $url = 'http://sim3015.aditi.lindenlab.com:12046/cap/5a1b89cd-e681-8110-7245-fb98969f32a0';

my $info = submitInformation( $url, {
    'action' => 'send message',
    'value'  => 'Hi there chief!',
    'id'     => '244195d6-c9b7-4fd6-9229-c3a8b2e60e81',
    'name'   => 'M Linden',
});

print($info,"\n");

Here is the coresponding Python script. It does the same thing as the Perl script above.

#!/usr/bin/python

import urllib
import re

# #################################################
# Routine to send the information to the prim
#     submitInformation(url,information)
#
def submitInformation(url,parameters) :
    
#    encodedParams =  urllib.urlencode(parameters);  # encode the parameters
    encodedParams  = dictionary2URI(parameters);    # encode the parameters
    net = urllib.urlopen(url,encodedParams);        # Post the data.
    return(net.read());                             # return the result.




# ################################################
# Routine to encode a dictionary without using 
# "+" for spaces.
#       dictionary2URI(theDictionary)
def dictionary2URI(theDictionary) : 

    encoded = '';           # Initialize the string to return
    for key, value in theDictionary.iteritems():
        # Encode each item in the dictionary.
        encoded += urllib.quote(key)+"="+urllib.quote(value)+"&";

    remove = re.compile('&$')             # Remove the trailing ampersand.
    encoded = remove.sub('',encoded);

    return(encoded);



if __name__ == "__main__":

    # Set the URL manually
    url = 'http://sim3015.aditi.lindenlab.com:12046/cap/5a1b89cd-e681-8110-7245-fb98969f32a0';

    # Define the parameters
    parameters = {'id':'244195d6-c9b7-4fd6-9229-c3a8b2e60e81',
                  'name':'M Linden',
                  'action':'send message',
                  'value':'Hey there, hi there, ho there!'};

    # Pass the information along to the prim
    info = submitInformation(url,parameters);
    print(info);

Simple script for sending data to an LSL via PHP

This example by Simba Fuhr UPDATE September 2, 2013NO LONGER WORKS PORTS 12046,12043 will not except incoming info from POST...

Warning!

Some hosting providers only allow fsockopen on the standard 80 and 443 ports. This script will not work on those providers. If your provider is willing to open some ports for you, HTTP-in uses port 12046, and HTTPS-in uses port 12043.

Note: To use SSL encrypted sockets, you need to have SSL activated on your server. If you run your own server, you need to import the ssl support to your server (apache => apache.conf +"LoadModule ssl_module modules/mod_ssl.so")(normaly based on openssl).

Secure URL Request with LSL. Script returns the URL to the chat. Please put the URL into the PHP below.

default
{
 state_entry()
 {
  llRequestSecureURL();
 }
 http_request(key id, string method, string body)
 {
  if ((method == URL_REQUEST_GRANTED))
  {
   llOwnerSay("URL: " + body);
  }
  else if (method == "POST")
  {
   llOwnerSay("PHP script sent: {" + body + "}");
   llHTTPResponse(id, 200, "PHP script sent: {" + body + "}");
  }
 }
}

Here the PHP. A more advanced php function which supports complete url structures and automatical GET and POST types. Just don't submit any post Data to make a GET request. The Function supports any kind of url as secure and not secure (https and http). If you dont submit a port in the url, the default port for http (80) and https (443) will be used. (An example is shown on the top of the script.)

<?php
echo "LSL Script answered:<br>";
echo Advanced_HTTP_Request("https://sim20557.agni.lindenlab.com:12043/cap/5851e666-b0c6-f0a0-758a-9e8156765215", "Hello script, how are you ?");

function Advanced_HTTP_Request($Host, $PostData = "")
{
 $Method = "POST";
 if (empty($PostData))
  {$Method = "GET";}
 $Port = 80;
 if (strtolower(substr($Host, 0, 5)) == "https")
  {$Port = 443;}
 $Host = explode("//", $Host, 2);
 if (count($Host) < 2)
  {$Host[1] = $Host[0];}
 $Host = explode("/", $Host[1], 2);
 if ($Port == 443)
  {$SSLAdd = "ssl://";}
 $Host[0] = explode(":", $Host[0]);
 if (count($Host[0]) > 1)
 {
  $Port = $Host[0][1];
  $Host[0] = $Host[0][0];
 }
 else
  {$Host[0] = $Host[0][0];}
 $Socket = fsockopen($SSLAdd.$Host[0], $Port, $Dummy1, $Dummy2, 10);
 if ($Socket)
 {
  fputs($Socket, "$Method /$Host[1] HTTP/1.1\r\n".
				 "Host: $Host[0]\r\n".
				 "Content-type: application/x-www-form-urlencoded\r\n".
				 "User-Agent: Opera/9.01 (Windows NT 5.1; U; en)\r\n".
				 "Accept-Language: de-DE,de;q=0.9,en;q=0.8\r\n".
				 "Accept-Charset: iso-8859-1, utf-8, utf-16, *;q=0.1\r\n".
				 "Content-length: ".strlen($PostData)."\r\n".
				 "Connection: close\r\n".
				 "\r\n".
				 $PostData);
  $Tme = time();
  while(!feof($Socket) && $Tme + 30 > time())
   {$Res = $Res.fgets($Socket, 256);}
  fclose($Socket);
 }
 $Res = explode("\r\n\r\n", $Res, 2);
 return $Res[1];
}
?>

Here is the simplest possible PHP persistant URL script, it could even be run on an old PC set up as a Linux web server from home. make a text file on the server, then call the page and write to the text file from the LSL script in your prim. reading the page will give you the SL URL for the prim.

<?php
$myfile = fopen("yourfile.txt", "w") or die("Unable to open file!");
$txt = $_POST['url'];
fwrite($myfile, $txt);
fclose($myfile);
?>

Kelly's Stupid Web Status Updater

Is actually on its own page: Kelly's Stupid Web Status Updater
Kurai's mod from Kelly's stupid thing: Kurai's Stupid Web Status Updater Mod

Web-based dynamic buildings

HTTP-in may be used to easily send commands from a web page to an in-world object, so that web users can control and interact with buildings. The interactive installation Chromutate is based upon this idea: see its documentation page for free scripts and more details.

PHP/SQL Object DNS

Simple DNS server written in PHP to facilitate a DNS service for LSL scripts: PHPDNS

HyperMedia (LSL Web Server)

An LSL web server that uses HTTP-In and Shared Media to serve and render a webpage (with working forms) on a prim: HyperMedia

Object to object HTTP communication

Go to Object to object HTTP communication for an example of inworld HTTP communication model.