How to monitor progress response of ajax request with jquery
I call an API that performs several lookups on the server. One call can result in 5-10 lookups. Each time a lookup is completed, the API appends a string to the GET response. When all lookups are completed, the connection is closed.
I'd like to have a callback that is triggered upon progress and preferrably find a a way of parsing the servers progress response (accessing the data) upon each completed lookup.
My problem is that the progress callback is never called.
This is my code so far. I tried to patch the xmlHttpRequest Object and extend jquery's ajax method.
(function addXhrProgressEvent($) {
var originalXhr = $.ajaxSettings.xhr;
$.ajaxSetup({
xhr : function() {
var req = originalXhr(), that = this;
if (req) {
if ( typeof req.addEventListener == "function" && that.progress !== undefined) {
req.addEventListener("progress", function(evt) {
that.progress(evt);
}, false);
}
if ( typeof req.upload == "object" && that.progressUpload !== undefined) {
req.upload.addEventListener("progress", function(evt) {
that.progressUpload(evt);
}, false);
}
}
return req;
}
});
})(jQuery);
$('#update').on('click', function(e) {
e.preventDefault();
var json = $.ajax({
headers : {
'Authorization' : "Basic " + btoa("abced:becd")
},
url : "http://123.123.123.123:5487/api/v1/check/" + $(this).attr('data-key'),
type : "GET",
crossDomain : true,
dataType : "text",
async : false,
progress : function(evt) {
/*this does not fire*/
alert('callback fired!');
/*this does not fire*/
if (evt.lengthComputable) {
console.log("Loaded " + parseInt((evt.loaded / evt.total * 100), 10) + "%");
} else {
console.log("Length not computable.");
}
},
success : function(data, textStatus, jqXHR) {
},
error : function(jqXHR, textStatus, errorThrown) {
}
});
});
});
This is the server's response
['task 1 completed']
\n
\n
\n
['task 3 completed']
\n
\n
\n
['task 4 completed']
...
Request Header
Accept text/plain, */*; q=0.01
Accept-Encoding gzip, deflate
Accept-Language de,en-US;q=0.7,en;q=0.3
Authorization Basic 12123456020600662232112311==
Host 123.123.123.123:1234
Origin http://123.123.123.132
Referer http://123.123.123.123/index.php/db/SSRelaunch
User-Agent Mozilla/5.0 (Windows NT 6.1; WOW64; rv:30.0) Gecko/20100101 Firefox/30.0
Response Header
Access-Control-Allow-Head... X-Requested-With, Content-Type, Authorization
Access-Control-Allow-Meth... GET,POST,PUT,OPTIONS
Access-Control-Allow-Orig... *
Content-Length 100000
Content-Type text/plain
Date Mon, 28 Jul 2014 18:06:27 GMT
Server BaseHTTP/0.3 Python/2.7.3
