osrm-backend/WebContent/OSRM.JSONP.js
2012-03-09 09:24:51 +01:00

77 lines
2.7 KiB
JavaScript

// OSRM JSONP call wrapper
// w/ DOM cleaning, fencing, timout handling
OSRM.JSONP = {
fences: {},
callbacks: {},
timeouts: {},
timers: {},
TIMEOUT: OSRM.DEFAULTS.JSONP_TIMEOUT,
late: function() { console.log("reply too late");},
empty: function() { console.log("empty callback");},
call: function(source, callback_function, timeout_function, timeout, id) {
// only one active JSONP call per id
if (OSRM.JSONP.fences[id] == true)
return false;
OSRM.JSONP.fences[id] = true;
// console.log("[status] jsonp init for "+id);
// console.log("[status] jsonp request ",source);
// wrap timeout function
OSRM.JSONP.timeouts[id] = function(response) {
timeout_function(response);
// var jsonp = document.getElementById('jsonp_'+id); // clean DOM
// if(jsonp)
// jsonp.parentNode.removeChild(jsonp);
OSRM.JSONP.callbacks[id] = OSRM.JSONP.late; // clean functions
OSRM.JSONP.timeouts[id] = OSRM.JSONP.late;
OSRM.JSONP.fences[id] = undefined; // clean fence
// console.log("timeout: "+id); // at the end - otherwise racing conditions may happen
// document.getElementById('information-box').innerHTML += "timeout:" + id + "<br>";
};
// wrap callback function
OSRM.JSONP.callbacks[id] = function(response) {
clearTimeout(OSRM.JSONP.timers[id]); // clear timeout timer
OSRM.JSONP.timers[id] = undefined;
if( OSRM.JSONP.fences[id] == undefined ) // fence to prevent execution after timeout function (when precompiled!)
return;
callback_function(response); // actual wrapped callback
// var jsonp = document.getElementById('jsonp_'+id); // clean DOM
// if(jsonp)
// jsonp.parentNode.removeChild(jsonp);
OSRM.JSONP.callbacks[id] = OSRM.JSONP.late; // clean functions
OSRM.JSONP.timeouts[id] = OSRM.JSONP.late;
OSRM.JSONP.fences[id] = undefined; // clean fence
// console.log("[status] jsonp response for "+id); // at the end - otherwise racing conditions may happen
// document.getElementById('information-box').innerHTML += "callback:" + id + "<br>";
};
// clean DOM (cannot reuse script element with all browsers, unfortunately)
var jsonp = document.getElementById('jsonp_'+id);
if(jsonp)
jsonp.parentNode.removeChild(jsonp);
// add script to DOM
var script = document.createElement('script');
script.type = 'text/javascript';
script.id = 'jsonp_'+id;
script.src = source + "&json_callback=OSRM.JSONP.callbacks."+id + "&jsonp=OSRM.JSONP.callbacks."+id;
document.head.appendChild(script);
// start timeout timer
OSRM.JSONP.timers[id] = setTimeout(OSRM.JSONP.timeouts[id], timeout);
return true;
}
};