Handling Asynchronous API Call in Jmeter - jmeter

I am using Jmeter for functional Testing, below is a problem that I am facing and need some help/suggestion on how to overcome that.
I have a thread-group that consists of 2 requests, 1st is API call and 2nd is sending message to Active MQ.
Now the flow is that I need to do first the API call (this will wait for response), then send the message to a particular Active MQ queue and then only I will get the response for the API.
But since jmeter does sequential execution of requests, its get stuck at the API call waiting for the reply and never executes the second part.
I worked on the below solution but even that did not help.
1 Use a parallel controller and put both the API and ACtive MQ call under the same.
2 Add a Timer to the Active MQ call, so that it just did after the API call (2 Sec)
But when I checked in details I see that both the requests are sent at the same time and the timer does not come into effect anywhere.
Any way I can handle this scenario?
Please note I will get a response to the API only when I send message to the particular Active MQ Queue, else it will timeout in a minute.

Your Parallel Controller approach will work, however you need to amend the configuration a little bit, something like:
You could put your ActiveMQ Request under a different Thread Group and use Inter-Thread Communication Plugin for synchronization between threads
You can keep the current setup but replace the JMS Sampler with the JSR223 Sampler and send the message to ActiveMQ programmatically:
Textual code representation for your convenicence:
sleep(2000)
def connectionFactory = new org.apache.activemq.ActiveMQConnectionFactory('your activemq URL')
def connection = connectionFactory.createConnection()
connection.start()
def session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE)
def destination = session.createQueue('your queue name')
def producer = session.createProducer(destination)
def message = session.createTextMessage('your message body')
producer.send(message)
connection.close()

For your Problem statement, following design will work.
Use 2 Thread Groups, add API call to first Thread group and Message to Active MQ call to second Thread Group
Add a delay to second Thread Group so that it should not run before first Thread Group
Run Test Plan

Use while controller. It will keep on executing till the desired outcome then the next request will be executed.
Hope this helps.
Update:-
While Loop controller execute its samplers until the condition specified is not set to False. The condition can be any variable or function that eventually evaluates to the string 'false'.
So, you need to specify a variable or function in While Loop, that has value 'true' and becomes 'false' somewhere else in the script. Once it changes to 'false', JMeter will exit the While loop.
For example if you are using a X-Path extractor in your script which have a variable named Status and its value changes from 'Start' to 'Finish' during the execution and you want to execute your script till 'Finish' has not been met, then you can use the expression ${__javaScript("'${imp_Status}'!='finish'",)} in your While loop and it will execute the samplers under While controller till the status = finish is met.
It is sort of polling based on certain condition. In your first API reponse, consider one value to be appear as the condition upon which first api call is successful.

It sounds that you just need to define timeout for HTTP Request,
If you define Response Timeout as 60000 (milliseconds), and it will only wait for a minute and then continue to next request
Connect Timeout Connection Timeout. Number of milliseconds to wait for a connection to open. No
Response Timeout Response Timeout. Number of milliseconds to wait for a response. Note that this applies to each wait for a response. If the server response is sent in several chunks, the overall elapsed time may be longer than the timeout.

Related

Is there anyway to hold response until we get full response from server in Jmeter?

The services I'm trying to test, will work on long pooling method.
They won't give results in first response.
When I run my API script I am not getting full response in first time.
How can I wait in this case for the remaining portion of response to be received?
I want to use values from this response into next call..
In the above screen my response should wait when complete:True
As far as I understand your requirement you need to repeat the Gethotels request until complete attribute becomes true.
In order to accomplish this:
Add a JSON Extractor as a child of the Gethotels request and set it up as follows:
Put your Gethotels request under the While Controller and use the following __jexl3() function as the condition:
${__jexl3("${complete}" != "true",)}
That's it, While Controller loop the Gethotels request until complete becomes true

How to use multiple sessions per connection in a multi-threaded application?

Suppose I have one connection c and many session objects s1, s2 .. sn, each working in different threads t1, t2 ... tn.
c
|
-------------------------------------------------
| | | |
(t1,s1) (t2,s2) (t3,s3) ...... (tn,sn)
Now suppose one of the thread t3 wants to send a message to a particular queue q3 and then listen to the reply asynchronously. So it does the following:
1: c.stop();
2: auto producer = s3.createProducer(s3.createQueue(q3));
3: auto text = s3.createTextMessage(message);
4: auto replyQueue = s3.createTemporaryQueue();
5: text.setJMSReplyTo(replyQueue);
6: producer.send(text);
7: auto consumer = s3.createConsumer(replyQueue);
8: consumer.setMessageListener(myListener);
9: c.start();
The reason why I called c.stop() in the beginning and then c.start() in the end, because I'm not sure if any of the other threads has called start on the connection (making all the sessions asynchronous — is that right?) and as per the documentation:
"If synchronous calls, such as creation of a consumer or producer, must be made on an asynchronous session, the Connection.Stop must be called. A session can be resumed by calling the Connection.Start method to start delivery of messages."
So calling stop in the beginning of the steps and then start in the end seems reasonable and thus the code seems correct (at least to me). However, when I thought about it more, I think the code is buggy, as it doesn't make sure no other threads call start before t3 finishes all the steps.
So my questions are:
Do I need to use mutex to ensure it? Or the XMS handles it automatically (which means my reasoning is wrong)?
How to design my application so that I dont have to call stop and start everytime I want to send a messages and listen reply asynchronously?
As per the quoted text above, I cannot call createProducer() and createConsumer() if the connection is in asynchronous mode. What are other methods I cannot call? The documentation doesn't categorise the methods in this way:
Also, the documentation doesn't say clearly what makes a session asynchronous. It says this:
"A session is not made asynchronous by assigning a message listener to a consumer. A session becomes asynchronous only when the Connection.Start method is called."
I see two problems here:
Calling c.start() makes all sessions asynchronous, not just one.
If I call c.start() but doesn't assign any message listener to a consumer, are the session(s) still asynchronous?
It seems I've lots of questions, so it'd be great if anyone could provide me with links to the parts or sections of the documentation which explains XMS objects with such minute details.
This says,
"According to the specification, calling stop(), close() on a Connection, setMessageListener() on a Session etc. must wait till all message processing finishes, that is till all onMessage() calls which have already been entered exit. So if anyone attempts to do that operation inside onMessage() there will be a deadlock by design."
But I'm not sure if that information is authentic, as I didn't find this info on IBM documentation.
I prefer the KIS rule. Why don't you use 1 connection per thread? Hence, the code would not have to worry about conflicts between threads.

Is it possible execute some action on thread failure in Jmeter?

Let's say I have a Jmeter test which emulate some user login and several more actions. I also have 'start new thread on error' turned on. So in case some user fail - it will just get another user and keep processing the test for specified amount of time.
But I have some periodic calls for authorized user and to emulate them I'll need to use "Inter-Thread Communication" and additional thread group(-s). Basically this works fine in following way - in main thread I do login and fill some FIFO queue with required cookies, and obtain that cookie in another thread group. In that another thread group I do also check one more FIFO queue (that is filled on user logout), and stop that thread if get what I need.
The problem here is when main thread is fail after login. In that case child thread will be executed 'forever', since that periodic call keeps session active.
And the question - is there some possibility in Jmeter to execute some action on thread failure (smth like finally block). Basically I need fill that second FIFO queue either on logout or on thread failure
Add a Beanshell Assertion at the same level as all your requests go. It'll apply to each of the requests and in case of failure you'll be able to do what your need.
Something like:
Thread Group
Login Sampler
Some other Sampler
Some else Sampler
Beanshell Assertion
The example assertion code:
if (!SampleResult.isSuccessful()){
log.info("Test " + SampleResult.getSampleLabel() + " has failed");
// handle the error
}
See How to Use JMeter Assertions in 3 Easy Steps guide for more information on JMeter Assertions.
I also had to logout on sample error which needs something like try-catch-finally. An IF Controller with condition ${JMeterThread.last_sample_ok} and checked Evaluate for all children? as below, satisfied my need in a clean way:
TestPlan
HTTP Cookie Manager
HTTP Request Defaults
ThreadGroup - (continue on error)
HTTP Request - login
IfController - (Evaluate ${JMeterThread.last_sample_ok} for all children)
HTTP Request 1
HTTP Request 2
....
HTTP Request n
HTTP Request - logout (after and outside of IF)

Typhoeus retry if fail

Currently, Typhoeus doesn't have automatic re-download in case of failure. What would be the best way of ensuring a retry if the download is not successful?
def request
request ||= Typhoeus::Request.new("www.example.com")
request.on_complete do |response|
if response.success?
xml = Nokogiri::XML(response.body)
else
# retry to download it
end
end
end
I think you need to refactor your code. You should have two queues and threads you're working with, at a minimum.
The first is a queue of URLs that you pull from to read via Typhoeus::Request.
If the queue is empty you sleep that thread for a minute, then look for a URL to retrieve. If you successfully read the page, parse it and push the resulting XML doc into a second queue of DOMs to work on. Process that from a second thread. And, if the second queue is empty, sleep that second thread until there is something to work on.
If reading a URL fails, automatically re-push it onto the first queue.
If both queues are empty you could exit the code, or let both threads sleep until something says to start processing URLs again and you repopulate the first queue.
You also need a retries-counter associated with the URL, otherwise if a site goes down you could retry forever. You could push little sub-arrays onto the queue as:
["url", 0]
where 0 is the retry, or get more complex using an object or define a class. Whatever you do, increment that counter until it hits a drop-dead value, then stop adding that to the queue and report it or remove it from your source of URLs database somehow.
That's somewhat similar to code I've written a couple times to handle big spidering tasks.
See Ruby's Thread and Queue classes for examples of this.
Also:
request ||= Typhoeus::Request.new("www.example.com")
makes no sense. request will be nil when that code runs, so the ||= will always fire. Instead use:
request = Typhoeus::Request.new("www.example.com")
modified with the appropriate code to pull the next value from the first queue mentioned above.

Long Running Wicket Ajax Request

I occasionally have some long running AJAX requests in my Wicket application. When this occurs the application is largely unusable as subsequent AJAX requests are queued up to process synchronously after the current request. I would like the request to terminate after a period of time regardless of whether or not a response has been returned (I have a user requirement that if this occurs we should present the user an error message and continue). This presents two questions:
Is there any way to specify a
timeout that's specific to an AJAX
or all AJAX request(s)?
If not, is there any way to kill the current request?
I've looked through the wicket-ajax.js file and I don't see any mention of a request timeout whatsoever.
I've even gone so far as to try re-loading the page after some timeout on the client side, but unfortunately the server is still busy processing the original AJAX request and does not return until the AJAX request has finished processing.
Thanks!
I think it won't help you to let the client 'cancel' the request. (However this could work.)
The point is that the server is busy processing a request that is not required anymore. If you want to timeout such operations you had to implement the timeout on the server side. If the operation takes too long, then the server aborts it and returns some error value as the result of the Ajax request.
Regarding your queuing problem: You may consider to use asynchronous requests in spite of synchronous ones. This means that the client first sends a request for starting the long running process. This request immediately returns. Then the client periodically polls the server and asks if the process has finished. Those poll requests also return immediately saying either that the process is still running or that it has finished with a certain result.
Failed solution: After a given setTimeout I kill the active transports and restart the channel, which handles everything on the client side. I avoided request conflicts by tying each to an ID and checking that against a global reference that increments each time a request is made and each time a request completes.
function longRunningCallCheck(refId) {
// make sure the reference id matches the global id.
// this indicates that we are still processing the
// long running ajax call.
if(refId == id){
// perform client processing here
// kill all active transport layers
var t = Wicket.Ajax.transports;
for (var i = 0; i < t.length; ++i) {
if (t[i].readyState != 0) {
t[i].onreadystatechange = Wicket.emptyFunction;
t[i].abort();
}
}
// process the default channel
Wicket.channelManager.done('0|s');
}
}
Unfortunately, this still left the PageMap blocked and any subsequent calls wait for the request to complete on the server side.
My solution at this point is to instead provide the user an option to logout using a BookmarkablePageLink (which instantiates a new page, thus not having contention on the PageMap). Definitely not optimal.
Any better solutions are more than welcome, but this is the best one I could come up with.

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