Working on JMeter and trying to send the soap request to server and shows the below error msg.
Error Msg:- Cannot process the message because the content type 'application/soap+msbin1' was not the expected type 'application/xml; charset=utf-8'.
We need help to encode XML to 'application/soap+msbin1' format.
Bit late to the party, but I encountered a similar issue - I had a template for SOAP request which uses embedded-binary XML (xop:Include cid="...") and had to scratch my head to figure out how to do that with the stock HTTP Request.
The answer: you can't - not in a simple way. To solve the issue, I ended up customizing JMeter (I also looked at HTTPRawRequest as well but it doesn't seem to support https and I would have to rewrite a lot of the test script to use that). Since HTTP request does 99% of the job, the quickest way to support binary data is to change the source code to handle binary data.
The main issues are two: the Function interface in JMeter is designed around returning String, not byte[]. So already __FileToString() (which I used to read an external binary file to use) encodes the content of the file . Secondly, the HTTP Request Sampler and HTTPHC4Impl itself (excluding the "upload file" bit) encodes the parts of the HTTP request before sending it over to the wire.
Changing that implied changes in Function, AbstractFunction, CompoundVariable and create a new function class FileToStringBinary which encode the binary data in a way that it can be decoded after (by changes made to HTTPHC4Impl).
If I have the time I'll find someplace where to post the idea and the source (can't submit to JMeter because my update to HTTPHC4Impl is limited to handle the specific requests I need to test, where the embedded binary is in a multipart/related part, and I have no time or inclination to handle the general cases), but if you still need help to make it work, drop a line.
I just read that some browsers would prevent HTTP polling (I guess by limiting the rate of requests)...
From https://github.com/sstrigler/JSJaC:
Note: As security restrictions of most modern browsers prevent HTTP
Polling from being usable anymore this module is disabled by default
now. If you want to compile it in use 'make polling'.
This could explain some misbehavior of some of my JavaScripts (sometimes requests are just not sent or retried, even if they were actually successful). But I couldn't find further information on details..
Questions
if it's "max. number of requests n per x seconds", what are the usual/default settings for x and n?
Is there any way good resource for this?
Any way to detect if a request has been "delayed" or "rejected" because of a rate limit?
Thanks for your help...
Stefan
Yes, as far as I am aware there is a default pool limit of 10 and a default request timeout of 30 seconds per request, however the timeout and poll limits can be controlled and different browsers implement different limitations!
Check out this Google implementation.
and this is an awesome implementation of catching a timeout error!
You can find the Firefox specifics HERE!
Internet Explorer specifics are controlled from inside the Windows registry.
Also have a look at this question.
Basically, the way you control is not by changing the browser limitations, but by abiding them. So you apply a technique called throttle-ing.
Think of it as creating a FIFO/priority queue of functions. A queue struct that takes xhr requests as members and enforces delay between them is an Xhr Poll. For instance, I am using
Jsonp to get data from a node.js server located on another domain and I am polling of course due to browser limitations. Otherwise, I get zero response back from the server and that is only because of browser limitations.
I am actually doing a console log for every request that's supposed to be sent, but not all of them are being logged. So the browser limits them.
I'll be even more specific with helping you out. I have a page on my website which is supposed to render a view for tens or even hundreds of articles. You go through them using a cool horizontal slider.
The current value of the slider matches the currrent 'page'. Since I am only displaying 5 articles per page and I can't exactly load thousands of articles 'onload' without severe performance implications, I load the articles for the current page. I get them from a MongoDB by sending a cross-domain request to a Python script.
The script is supposed to return an array of five objects with all the details I need to build the DOM elements for a 'page'. However, there are a couple of issues.
First, the slider works extremely fast, as it's more or less a value change. Even if there is drag drop functionality, key down events etc, the actual change takes miliseconds. However, the code of the slider looks something like this:
goog.events.listen(slider, goog.events.EventType.CHANGE, function() {
myProject.Articles.page(slider.getValue());
}
The slider.getValue() method returns an int with the current page number, so basically I have to load from:
currentPage * articlesPerPage to (currentPage * articlesPerPage + 1) - 1
But in order to load, i do something like this:
I have a storage engine(think of it as an array):
I check if the content is not already there
If it is, there is no point to make another request, so go forward with getting the DOM elements from the array with the already created DOM elements in place.
If it isn't, then I need to get it so I need to send that request I was mentioning, which would look something like(without accounting for browser limitations):
JSONP.send({'action':'getMeSomeArticles','start':start,'length': itemsPerPage, function(callback){
// now I just parse the callback quickly to make sure it is consistent
// create DOM elements, and populate the client side storage
// and update the view for the user.
}}
The problem comes from the speed with which you can change that slider. Since every change supposedly triggers a request(same would happen for normal Xhr requests), then you are basically crossing the limitations of all browsers, so without throttle-ing, there would be no 'callback' for most of the requests. 'callback' is the JS code returned by the JSONP request(which is more of a remote script inclusion than anything else).
So what I do is push a request to a priority queue, not POLL, as now I don't need to send multiple simultaneous requests. If the queue is empty, the recently added member is executed and everyone is happy. If it's not, then all non-completed requests in progress are cancelled and only the last one is executed.
Now in my particular case, I do a binary search(0(log n)) to see if the storage engine doesn't have data for the previous requests yet, which tells me if the previous request has been completed or not. If it has, then it's removed from the queue and the current one is processed, otherwise the new one fires. So an and so forth.
Again, for speed consideration and shit browser wanna-bes such as Internet Explorer, I do the above described procedure about 3-4 steps ahead. So I pre-load 20 pages ahead till everything is the client side storage engine. This way, every limitation is successfully dealt with.
The cooldown time is covered by the minimum time it would take to slide through 20 pages and the throttle-ing makes sure there are no more than 1 active requests at any given time(with backwards compatibility going as far as Internet Explorer 5).
The reason why I wrote all this is to give you an example trying to say that you cannot always enforce delay directly from the FIFO structure, as your calls may need to turn into what a user sees, and you don't exactly want to make a user wait 10-15 seconds for a single page to render.
Also, always minimize the polling and the need to poll(simultaneously fired Ajax events, as not all browsers actually do good things with them). For instance, instead of doing something like sending one request to get content and sending another for that content to be tracked as viewed in your app metrics, do as many tasks at server level as you possibly can!
Of course, you probably want to track your errors properly, so your Xhr object from your library of choice implement error handling for ajax and because you are an awesome developer you want to make use of them.
so say you have a try - catch block in place
The scenario is this:
An Ajax call has finished and it's supposed to return a JSON, but the call somehow failed. However, you try to parse the JSON and do whatever you need to do with it.
so
function onAjaxSuccess (ajaxResponse) {
try {
var yourObj = JSON.parse(ajaxRespose);
} catch (err) {
// Now I've actually seen this on a number of occasions, to log that an error occur
// a lot of developers will attempt to send yet another ajax request to log the
// failure of the previous one.
// for these reasons, workers exist.
myProject.worker.message('preferrably a pre-determined error code should go here');
// Then only the worker should again throttle and poll the ajax requests that log the
//specific error.
};
};
While I have seen various implementations that try to fire as many Xhr requests at the same time as they possible can until they encounter browser limitations, then do quite a good job at stalling the ones that haven't fired in wait for the browser 'cooldown', what I can advise you is to think about the following:
How important is speed for your app?
Just how scalable and how intensive the I/O will be?
If the answer to the first one is 'very' and to the latter 'OMFG modern technology', then try to optimize your code and architecture as much as you can so that you never need to send 10 simultaneous Xhr requests. Also, for large scale apps, multi-thread your processes. The JavaScript way to accomplish that is by using workers. Or you could call the ECMA board, tell them to make this a default, and then post it here so that the rest of us JS devs can enjoy native multi-threading in JS:)(how dafuq did they not think about this?!?!)
Stefan, quick answers below:
-if it's "max. number of requests n per x seconds", what are the usual/default settings for x and n?
This sounds more like a server restriction. The browser ones usually sound like:
-"the maximum requests for the same hostname is x"
-"the maximum connections for ANY hostname is y"
-Is there any way good resource for this?
http://www.browserscope.org/?category=network (also hover over table headers to see what is measured)
http://www.stevesouders.com/blog/2008/03/20/roundup-on-parallel-connections
-Any way to detect if a request has been "delayed" or "rejected" because of a rate limit?
You could look at the http headers for "Connection: close" to detect server restrictions but I am not aware of being able in JavaScript to read settings from so many browsers in a consistent, browser-independent way. (For Firefox, you could read this http://support.mozilla.org/en-US/questions/746848)
Hope this quick answer helps?
No, browser does not in any way affect polling. I think what was meant on that page is the same origin policy - you can only access the same host and port as your original page.
Only known limitation to connections themselves is that you usually can only have from two to four simultaneous connections to the same host.
I've written some apps with long poll, some with C++ backend with my own webserver, and one with PHP backend with Apache2.
My long poll timeout is 4..10 s. When something occurs, or 4..10 s passes, my server returns an empty response. Then the client immediatelly starts another AJAX request. I found that some browsers hangs up when I start AJAX call from previous AJAX handler, so I am using setTimeout() with a small value to start the next AJAX request.
When something happens on the client side, which should be sent to server, I use another AJAX request for it, but it's a one-way thing: the server does not send any response, and the client does not process anything. The result of the operation (if any) will be received on the long poll. It requires max. 2 connection to the server, which all browsers supports.
Keep in mind, that if there's 500 client, it means 500 server-side webserver thread, which will move together, occurring load peaks, because when something happens, the server have to report it at the same time for each clients, the clients will process it near same time long, they will start the next long request in the same time, and from then, the timeout will expire also at the same time, and furthcoming ones too. You can trick with rnd timeout, say 4 rnd(0..4), but it's worthless, if anything happens, they will "sync" again, all the request have to be served at the same time, when something reportable happens.
I've tested it thru a router, and it works. I assume, routers respects 4..10 lag, it's around the speed of a slow webapge (far, far away), which no router think, that it should be canceled.
My PHP work is a collaborative spreadsheet, it looks amazing when you hit enter and the stuff is updating simultaneously in several browsers. Have fun!
No limit for no of ajax requests. However it will be on same host & port.
Server can limit no of request from a machine based on its setting.
For example. A server can set so that if there are more than few request from same machine within specified time it will reject request.
After small mistake in javascript code, neverending loop was made witch each step calling 2 ajax requests. In firebug i could see more and more requests until firefox started to slow down, dont response and finally crash.
So, yes, there is a "limit" ;)
i found sometime image request are passed with prams.
what is the meaning of those prams?
let's have a example.
someimageurl.png?c=34
what is the meaning of the "c=34"
i found it in css, JavaScript file also
It's up to the server that the image request arrives at to do something with any parameters on the image request. There is no standard meaning of those parameters as they can be designed by the server to do anything they want.
To know what those particular parameters do that you're asking about, one would either have to reverse engineer it by looking at the whole application and seeing how they are being used in that application (and try to figure it out) or would have to see the actual server code to see what it does with them.
I am trying to create real-time and collaborative application like - google wave for example.
When user1 writes something at the same time it shows on user2 screens.
I started a little research,and found some ways to this with Ajax -
1.every X seconds send request to the server and to check what is "happening"
2.timeout - long request ,Problem - I saw i can do this only with IE8
there are other options?what is the best way to this?
And with way number 2,this true I can do this only with IE8?
Yosy
The whole point of AJAX is that the server can wait for notifications from each clients, and notify all the other clients when something happens. There's no need for polling. Look up keywords like comet, and bayeux. Dojo has a good implementation.
I'm not sure what you are referring to in 2, but if I were going to implement something like this, I'd do what you explain in 1. Basically your server will be keeping track of the conversation, and the clients will constantly ask for updates.
Another possible option would be flash, but I don't know much about that other than it would be capable, so your on your own for researching that.
Some notes on keeping things running quickly in option 1:
Remember you only have 2 "ajax"
calls to work with on the client side (you can only have 2 calls
out at once). So keep track
of the calls that are out. Make use
of abort() if a call takes too long or its response is not going to be valid anymore.
Get the most out of your calls, if
you need to send text to the server,
use the response to get an update on
the current "conversation".
What are the strengths of GET over POST and vice versa when creating an ajax request? How do I know which I should use at any given time? Is it a security-minded decision?
Also, what is the difference in how they are actually sent?
GETs should be used for idempotent operations, that is operations that can be safely repeated more than once without changing anything. Browsers will cache GET requests (for normal and AJAX requests)
POSTs should be generally be used for non-idenpotent operations, like saving something. Although you can use them for other operations if you want.
Data for GETs is sent over the URL query string. Data for POSTs is sent separately. Some browsers have a maximum URL length (I think Internet Explorer is 2048 characters), and if the query string becomes too long you'll get an error.
You should use GET and POST requests in AJAX calls just as you would use GET and POST requests in normal calls. Basic rule of thumb:
Will the request modify anything in your Model?
YES: The request will modify (add/update/delete) data from your data store,
or in some other way change the state of the server (cause creation of
a file, for example). Use POST.
NO: The request will not affect the state of anything (database, file system,
sessions, ...) on the server, but merely retrieve information. Use GET.
POST requests are requests that you do not want to accidentally happen. GET requests are requests you are OK with happening by a user pointing a browser to via a URL.
GET requests can be repeated quite simply since their data is based in the URL itself.
You should think about AJAX requests like you think about regular form requests (and their GET and POST)
The Yahoo! Mail team found that when using XMLHttpRequest, POST is implemented in the browsers as a two-step process: sending the headers first, then sending data. So it's best to use GET, which only takes one TCP packet to send (unless you have a lot of cookies). The maximum URL length in IE is 2K, so if you send more than 2K data you might not be able to use GET.
http://developer.yahoo.com/performance/rules.html#ajax_get