Helping me understand session api Gatling - gatling

I am new to gatling
I am trying to loop on json response, find the country code that I am looking for and take the id coressponding the that coutry code.
Sample algorithm:
list.foreach( value => { if (value.coutrycode == "PL") then store value.id })
on Gatling:
def getOffer() = {
exec(
http("GET /offer")
.get("/offer")
.check(status.is(Constant.httpOk))
.check((bodyString.exists),
jsonPath("$[*]").ofType[Map[String,Any]].findAll.saveAs("offerList")))
.foreach("${offerList}", "item"){
exec(session => {
val itemMap = session("item").as[Map[String,Any]]
val countryCodeId = itemMap("countryCode")
println("****" + countryCodeId)
// => print all the country code on the list
if (countryCodeId =="PL"){ // if statement condition
println("*************"+ itemMap("offerd")); // print the id eg : "23"
session.set("offerId", itemMap("offerId")); // set the id on the session
}
println("$$$$$$$$$$$$$$" + session("offerId")) // verify that th session contains the offerId but is not
session
})
}
}
When I try to print the session("offerId"), it's print "item" and not the offerId.
I looked on the documentation but I didn't understand the behaviour. Could you please explain it to me ?

It's all in the documentation.
Session instances are immutable!
Why is that so? Because Sessions are messages that are dealt with in a
multi-threaded concurrent way, so immutability is the best way to deal
with state without relying on synchronization and blocking.
A very common pitfall is to forget that set and setAll actually return
new instances.
val session: Session = ???
// wrong usage
session.set("foo", "FOO") // wrong: the result of this set call is just discarded
session.set("bar", "BAR")
// proper usage
session.set("foo", "FOO").set("bar", "BAR")
So what you want is:
val newSession =
if (countryCodeId =="PL"){ // if statement condition
println("*************"+ itemMap("offerd")); // print the id eg : "23"
session.set("offerId", itemMap("offerId")); // set the id on the session
} else {
session
}
// verify that the session contains the offerId
println("$$$$$$$$$$$$$$" + newSession("offerId").as[String])
newSession

Related

Gatling how to store and load a value for a later request

I'd like to build a load test where the second request is fed from first response. The data extraction is done in a method because it is not only one line of code. My problem is storing the value (id) and load it later. How should the value be stored and loaded? I tried some different approaches, and I come up with this code. The documentation has not helped me.
object First {
val first = {
exec(http("first request")
.post("/graphql")
.headers(headers_0)
.body(RawFileBody("computerdatabase/recordedsimulation/first.json"))
.check(bodyString.saveAs("bodyResponse"))
)
.exec {
session =>
val response = session("bodyResponse").as[String]
session.set("Id", getRandomValueForKey("id", response))
session}
.pause(1)
}
}
object Second {
val second = {
exec(http("Second ${Id}")
.post("/graphql")
.headers(headers_0)
.body(RawFileBody("computerdatabase/recordedsimulation/second.json"))
)
.pause(1)
}
}
val user = scenario("User")
.exec(
First.first,
Second.second
)
setUp(user.inject(
atOnceUsers(1),
)).protocols(httpProtocol)
Your issue is that you're not using the Session properly.
From the documentation:
Warning
Session instances are immutable!
Why is that so? Because Sessions are messages that are dealt with in a multi-threaded concurrent way, so immutability is the best way to deal with state without relying on synchronization and blocking.
A very common pitfall is to forget that set and setAll actually return new instances.
This is exactly what you're doing:
exec { session =>
val response = session("bodyResponse").as[String]
session.set("Id", getRandomValueForKey("id", response))
session
}
It should be:
exec { session =>
val response = session("bodyResponse").as[String]
session.set("Id", getRandomValueForKey("id", response))
}

Gatling - print current time before execution of scenario and pass that value to next scenario

I am executing 2 consecutive scenarios, I have a requirement where I need to record current time before start of 1st scenario and then pass that time value to next scenario. Can someone please suggest how this can be implemented. Please check below my code
def fileUpload() = foreach("${datasetIdList}","datasetId"){
println("File Upload Start Time::::"+Calendar.getInstance().getTime+" for datasetId ::: ${datasetId}")
exec(http("file upload").post("/datasets/${datasetId}/uploadFile")
.formUpload("File","./src/test/resources/data/Scan_good.csv")
.header("content-type","multipart/form-data")
.check(status is 200).check(status.saveAs("uploadStatus")))
.exec(session => {
if(session("uploadStatus").as[Int] == 200)
counter +=1
session
})
}
def getDataSetId() = foreach("${datasetIdList}","datasetId"){
exec(http("get datasetId")
.get("/datasets/${datasetId}")
.header("content-type","application/json")
.check(status is 200)
)
I need to record upload start time for each iteration of datasetIdList and pass that value to next scenario and print that value for each datasetId. can someone please suggest how this can be implemented
You may try using before section
package load
import io.gatling.core.Predef._
import io.gatling.http.Predef._
class TransferTimeSimulation extends Simulation {
var beforeScn1Start: Long = 0L
before {
println("Simulation is about to start!")
beforeScn1Start = System.currentTimeMillis()
}
after {
println("Simulation is finished!")
}
val scn1 = scenario("Scenario 1").exec(
http("get google")
.get("http://google.com")
.check(status.is(200))
)
val scn2 = scenario("Scenario 2")
.exec { session =>
println("beforeScn1Start = " + beforeScn1Start)
session
}
setUp(
scn1.inject(atOnceUsers(1))
.andThen(scn2.inject(atOnceUsers(1)))
)
.protocols(http)
.maxDuration(10)
.assertions(
forAll.failedRequests.count.is(0),
)
}
For more flexibilty you may also consider using lazy val initialization
https://www.baeldung.com/scala/lazy-val

Gatling2 Failing to use user session properly

I hope someone can point me into the right direction!
I try to run one scenario which has several steps that have to be executed in order and each with the same user session to work properly. The below code works fine with one user but fails if I use 2 or more users...
What am I doing wrong?
val headers = Map(
Constants.TENANT_HEADER -> tenant
)
val httpConf = http
.baseURL(baseUrl)
.headers(headers)
val scen = scenario("Default Order Process Perf Test")
.exec(OAuth.getOAuthToken(clientId))
.exec(session => OAuth.createAuthHHeader(session, clientId))
.exec(RegisterCustomer.registerCustomer(customerMail, customerPassword,
tenant))
.exec(SSO.doLogin(clientId, customerMail, customerPassword, tenant))
.exec(session => OAuth.upDateAuthToken(session, clientId))
.exec(session =>
UpdateCustomerBillingAddr.prepareBillingAddrRequestBody(session))
.exec(UpdateCustomerBillingAddr.updateCustomerBillingAddr(tenant))
.exec(RegisterSepa.startRegisterProcess(tenant))
.exec(session => RegisterSepa.prepareRegisterRequestBody(session))
.exec(RegisterSepa.doRegisterSepa(tenant))
setUp(
scen
.inject(atOnceUsers(2))
.protocols(httpConf))
object OAuth {
private val OBJECT_MAPPER = new ObjectMapper()
def getOAuthToken(clientId: String) = {
val authCode = PropertyUtil.getAuthCode
val encryptedAuthCode = new
Crypto().rsaServerKeyEncrypt(authCode)
http("oauthTokenRequest")
.post("/oauth/token")
.formParam("refresh_token", "")
.formParam("code", encryptedAuthCode)
.formParam("grant_type", "authorization_code")
.formParam("client_id", clientId)
.check(jsonPath("$").saveAs("oauthToken"))
.check(status.is(200))
}
def createAuthHHeader(session: Session, clientId: String) = {
val tokenString = session.get("oauthToken").as[String]
val tokenDto = OBJECT_MAPPER.readValue(tokenString,
classOf[TokenDto])
val session2 = session.set(Constants.TOKEN_DTO_KEY, tokenDto)
val authHeader = AuthCommons.createAuthHeader(tokenDto,
clientId, new util.HashMap[String, String]())
session2.set(Constants.AUTH_HEADER_KEY, authHeader)
}
def upDateAuthToken(session: Session, clientId: String) = {
val ssoToken = session.get(Constants.SSO_TOKEN_KEY).as[String]
val oAuthDto = session.get(Constants.TOKEN_DTO_KEY).as[TokenDto]
val params = new util.HashMap[String, String]
params.put("sso_token", ssoToken)
val updatedAuthHeader = AuthCommons.createAuthHeader(oAuthDto,
clientId, params)
session.set(Constants.AUTH_HEADER_KEY, updatedAuthHeader)
}
}
def createAuthHHeader(session: Session, clientId: String) = {
val tokenString = session.get("oauthToken").as[String]
val tokenDto = OBJECT_MAPPER.readValue(tokenString,
classOf[TokenDto])
val session2 = session.set(Constants.TOKEN_DTO_KEY, tokenDto)
val authHeader = AuthCommons.createAuthHeader(tokenDto,
clientId, new util.HashMap[String, String]())
session2.set(Constants.AUTH_HEADER_KEY, authHeader)
}
So I did add the two methods that dont work along as expected. In the first part I try to fetch a token and store in the session via check(jsonPath("$").saveAs("oauthToken")) and in the second call I try to read that token with val tokenString = session.get("oauthToken").as[String] which fails with the exception saying that there is no entry for that key in the session...
I've copied it and removed/mocked any missing code references, switched to one of my apps auth url and it seems to work - at least 2 firsts steps.
One thing that seems weird is jsonPath("$").saveAs("oauthToken") which saves whole json (not single field) as attribute, is it really what you want to do? And are you sure that getOAuthToken is working properly?
You said that it works for 1 user but fails for 2. Aren't there any more errors? For debug I suggest changing logging level to TRACE or add exec(session => {println(session); session}) before second step to verify if token is properly saved to session. I think that something is wrong with authorization request (or building that request) and somehow it fails or throws some exception. I would comment out all steps except 1st and focus on checking if that first request is properly executed and if it adds proper attribute to session.
I think your brackets are not set correctly. Change them to this:
setUp(
scn.inject(atOnceUsers(2))
).protocols(httpConf)

How to increment a variable in Gatlling Loop

I am trying to write a Gatling script where I read a starting number from a CSV file and loop through, say 10 times. In each iteration, I want to increment the value of the parameter.
It looks like some Scala or Java math is needed but could not find information on how to do it or how and where to combine Gatling EL with Scala or Java.
Appreciate any help or direction.
var numloop = new java.util.concurrent.atomic.AtomicInteger(0)
val scn = scenario("Scenario Name")
.asLongAs(_=> numloop.getAndIncrement() <3, exitASAP = false){
feed(csv("ids.csv")) //read ${ID} from the file
.exec(http("request")
.get("""http://finance.yahoo.com/q?s=${ID}""")
.headers(headers_1))
.pause(284 milliseconds)
//How to increment ID for the next iteration and pass in the .get method?
}
You copy-pasted this code from Gatling's Google Group but this use case was very specific.
Did you first properly read the documentation regarding loops? What's your use case and how doesn't it fit with basic loops?
Edit: So the question is: how do I get a unique id per loop iteration and per virtual user?
You can compute one for the loop index and a virtual user id. Session already has a unique ID but it's a String UUID, so it's not very convenient for what you want to do.
// first, let's build a Feeder that set an numeric id:
val userIdFeeder = Iterator.from(0).map(i => Map("userId" -> i))
val iterations = 1000
// set this userId to every virtual user
feed(userIdFeeder)
// loop and define the loop index
.repeat(iterations, "index") {
// set an new attribute named "id"
exec{ session =>
val userId = session("userId").as[Int]
val index = session("index").as[Int]
val id = iterations * userId + index
session.set("id", id)
}
// use id attribute, for example with EL ${id}
}
Here is my answer to this:
Problem Statement: I had to repeat the gatling execution for configured set of times, and my step name has to be dynamic.
object UrlVerifier {
val count = new java.util.concurrent.atomic.AtomicInteger(0)
val baseUrl = Params.applicationBaseUrl
val accessUrl = repeat(Params.noOfPagesToBeVisited,"index") {
exec(session=> {
val randomUrls: List[String] = UrlFeeder.getUrlsToBeTested()
session.set("index", count.getAndIncrement).set("pageToTest", randomUrls(session("index").as[Int]))
}
).
exec(http("Accessing Page ${pageToTest}")
.get(baseUrl+"${pageToTest}")
.check(status.is(200))).pause(Params.timeToPauseInSeconds)
}
So basically UrlFeeder give me list of String (urls to be tested) and in the exec, we are using count (AtomicInteger), and using this we are populating a variable named 'index' whose value will start from 0 and will be getAndIncremented in each iteration. This 'index' variable is the one which will be used within repeat() loop as we are specifying the name of counterVariable to be used as 'index'
Hope it helps others as well.

In Firebase, is there a way to get the number of children of a node without loading all the node data?

You can get the child count via
firebase_node.once('value', function(snapshot) { alert('Count: ' + snapshot.numChildren()); });
But I believe this fetches the entire sub-tree of that node from the server. For huge lists, that seems RAM and latency intensive. Is there a way of getting the count (and/or a list of child names) without fetching the whole thing?
The code snippet you gave does indeed load the entire set of data and then counts it client-side, which can be very slow for large amounts of data.
Firebase doesn't currently have a way to count children without loading data, but we do plan to add it.
For now, one solution would be to maintain a counter of the number of children and update it every time you add a new child. You could use a transaction to count items, like in this code tracking upvodes:
var upvotesRef = new Firebase('https://docs-examples.firebaseio.com/android/saving-data/fireblog/posts/-JRHTHaIs-jNPLXOQivY/upvotes');
upvotesRef.transaction(function (current_value) {
return (current_value || 0) + 1;
});
For more info, see https://www.firebase.com/docs/transactions.html
UPDATE:
Firebase recently released Cloud Functions. With Cloud Functions, you don't need to create your own Server. You can simply write JavaScript functions and upload it to Firebase. Firebase will be responsible for triggering functions whenever an event occurs.
If you want to count upvotes for example, you should create a structure similar to this one:
{
"posts" : {
"-JRHTHaIs-jNPLXOQivY" : {
"upvotes_count":5,
"upvotes" : {
"userX" : true,
"userY" : true,
"userZ" : true,
...
}
}
}
}
And then write a javascript function to increase the upvotes_count when there is a new write to the upvotes node.
const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
exports.countlikes = functions.database.ref('/posts/$postid/upvotes').onWrite(event => {
return event.data.ref.parent.child('upvotes_count').set(event.data.numChildren());
});
You can read the Documentation to know how to Get Started with Cloud Functions.
Also, another example of counting posts is here:
https://github.com/firebase/functions-samples/blob/master/child-count/functions/index.js
Update January 2018
The firebase docs have changed so instead of event we now have change and context.
The given example throws an error complaining that event.data is undefined. This pattern seems to work better:
exports.countPrescriptions = functions.database.ref(`/prescriptions`).onWrite((change, context) => {
const data = change.after.val();
const count = Object.keys(data).length;
return change.after.ref.child('_count').set(count);
});
```
This is a little late in the game as several others have already answered nicely, but I'll share how I might implement it.
This hinges on the fact that the Firebase REST API offers a shallow=true parameter.
Assume you have a post object and each one can have a number of comments:
{
"posts": {
"$postKey": {
"comments": {
...
}
}
}
}
You obviously don't want to fetch all of the comments, just the number of comments.
Assuming you have the key for a post, you can send a GET request to
https://yourapp.firebaseio.com/posts/[the post key]/comments?shallow=true.
This will return an object of key-value pairs, where each key is the key of a comment and its value is true:
{
"comment1key": true,
"comment2key": true,
...,
"comment9999key": true
}
The size of this response is much smaller than requesting the equivalent data, and now you can calculate the number of keys in the response to find your value (e.g. commentCount = Object.keys(result).length).
This may not completely solve your problem, as you are still calculating the number of keys returned, and you can't necessarily subscribe to the value as it changes, but it does greatly reduce the size of the returned data without requiring any changes to your schema.
Save the count as you go - and use validation to enforce it. I hacked this together - for keeping a count of unique votes and counts which keeps coming up!. But this time I have tested my suggestion! (notwithstanding cut/paste errors!).
The 'trick' here is to use the node priority to as the vote count...
The data is:
vote/$issueBeingVotedOn/user/$uniqueIdOfVoter = thisVotesCount, priority=thisVotesCount
vote/$issueBeingVotedOn/count = 'user/'+$idOfLastVoter, priority=CountofLastVote
,"vote": {
".read" : true
,".write" : true
,"$issue" : {
"user" : {
"$user" : {
".validate" : "!data.exists() &&
newData.val()==data.parent().parent().child('count').getPriority()+1 &&
newData.val()==newData.GetPriority()"
user can only vote once && count must be one higher than current count && data value must be same as priority.
}
}
,"count" : {
".validate" : "data.parent().child(newData.val()).val()==newData.getPriority() &&
newData.getPriority()==data.getPriority()+1 "
}
count (last voter really) - vote must exist and its count equal newcount, && newcount (priority) can only go up by one.
}
}
Test script to add 10 votes by different users (for this example, id's faked, should user auth.uid in production). Count down by (i--) 10 to see validation fail.
<script src='https://cdn.firebase.com/v0/firebase.js'></script>
<script>
window.fb = new Firebase('https:...vote/iss1/');
window.fb.child('count').once('value', function (dss) {
votes = dss.getPriority();
for (var i=1;i<10;i++) vote(dss,i+votes);
} );
function vote(dss,count)
{
var user='user/zz' + count; // replace with auth.id or whatever
window.fb.child(user).setWithPriority(count,count);
window.fb.child('count').setWithPriority(user,count);
}
</script>
The 'risk' here is that a vote is cast, but the count not updated (haking or script failure). This is why the votes have a unique 'priority' - the script should really start by ensuring that there is no vote with priority higher than the current count, if there is it should complete that transaction before doing its own - get your clients to clean up for you :)
The count needs to be initialised with a priority before you start - forge doesn't let you do this, so a stub script is needed (before the validation is active!).
write a cloud function to and update the node count.
// below function to get the given node count.
const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
exports.userscount = functions.database.ref('/users/')
.onWrite(event => {
console.log('users number : ', event.data.numChildren());
return event.data.ref.parent.child('count/users').set(event.data.numChildren());
});
Refer :https://firebase.google.com/docs/functions/database-events
root--|
|-users ( this node contains all users list)
|
|-count
|-userscount :
(this node added dynamically by cloud function with the user count)

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