How to manually throw HTTP 404 Not Found exception in spray/akka? - scala

In my repository function, I'm reading a User, then updating that user:
def update(u: User): Future[Int] = {
this.read(u.id).flatMap {
case Some(existingUser) =>
db.run(
userTable
.filter(_.id === user.id)
.update(user.copy(createdDate = existingUser.createdDate)))
//case None => throw new NotFoundException(); // does this exception exist in spray/akka?
}
}
I'd like to throw some sort of exception here when the user is not found, so that spray/akka will know that exception means to return HTTP 404 Not Found.
Does spray/akka contain some sort of NotFoundException that I can manually throw?

You can throw any exception and then configure an exception handler to convert the exception to 404 response.

Does it have to be an exception, or could you use this:
case None => HttpResponse(StatusCodes.NotFound)

Related

Response entity was not subscribed after 100 seconds. Make sure to read the response entity body or call `discardBytes()` on it

I am building a scala application. Within the application, we are making a call to an external service, and fetching the data.
When I am hitting the endpoint of this external service using the
postman, I am getting the complete data, around 9000 lines of JSON
data, within 9 seconds.
But when I am hitting the same endpoint through my scala application, I am getting a 200 OK response, but getting the below error:
[WARN] [06/09/2022 18:05:45.765] [default-akka.actor.default-dispatcher-9] [default/Pool(shared->http://ad-manager-api-production.ap-south-1.elasticbeanstalk.com:80)] [4 (WaitingForResponseEntitySubscription)] Response entity was not subscribed after 100 seconds. Make sure to read the response entity body or call `discardBytes()` on it. GET /admin/campaigns Empty -> 200 OK Chunked
I read about it and found that we can set response-entity-subscription-timeout property to a higher value. I set it to about 100 seconds, but this does not seem to help.
My Code:
private val sendAndReceive = customSendAndReceive.getOrElse(HttpClientUtils.singleRequest)
.
.
.
def getActiveCampaigns: GetActiveCampaigns = () => {
val request = HttpRequest(
uri = s"$endpoint/admin/campaigns?status=PUBLISHED", // includes both PUBLISHED_READY and PUBLISHED_PAUSED
method = HttpMethods.GET,
headers = heathers
)
sendAndReceive(request).timed(getActiveCampaignsTimer).flatMap {
case HttpResponse(StatusCodes.OK, _, entity, _) =>
Unmarshal(entity).to[List[CampaignListDetailsDto]]
case response#HttpResponse(_, _, _, _) =>
response.discardEntityBytes()
Future.failed(new RuntimeException(s"Ad manager service exception: $response"))
case response =>
log.error(s"Error calling ad manager service: $response")
response.discardEntityBytes()
Future.failed(new RuntimeException(s"Ad manager service exception: $response"))
}
}
.
.
.
def getCampaignSpendData(getActiveCampaigns: GetActiveCampaigns, getCampaignTotalSpend: GetCampaignTotalSpend)(implicit ec: ExecutionContext): GetCampaignsSpendData = () => {
getActiveCampaigns()
.andThen {
case Failure(t) => log.error("Failed to fetch ads from ad manager", t)
}
.flatMap {
campaignList => Future.sequence(campaignList.map(campaign => budgetSpendPercentage(getCampaignTotalSpend)(campaign)))
}
}
Questions
What does this error exactly mean? Is it that it is able to connect to the endpoint but not able to get the complete data from it before the connection is closed/reset?
How can we address this issue?

Akka Http route test with formFields causing UnsupportedRequestContentTypeRejection

I have a GET request with parameters and a formField.
It works when I use a client like Insomnia/Postman to send the req.
But the route test below fails with the error:
UnsupportedRequestContentTypeRejection(Set(application/x-www-form-urlencoded, multipart/form-data))
(Rejection created by unmarshallers. Signals that the request was rejected because the requests content-type is unsupported.)
I have tried everything I can think of to fix it but it still returns the same error.
It is the formField that causes the problem, for some reason when called by the test it doesnt like the headers.
Is it something to do with withEntity ?
Code:
path("myurl" ) {
get {
extractRequest { request =>
parameters('var1.as[String], 'var2.as[String], 'var3.as[String], 'var4.as[String]) { (var1, var2, var3, var4) =>
formField('sessionid.as[String]) { (sessionid) =>
complete {
request.headers.foreach(a => println("h=" + a))
}
}
}
}
}
}
Test:
// TESTED WITH THIS - Fails with UnsupportedRequestContentTypeRejection(Set(application/x-www-form-urlencoded, multipart/form-data))
class GETTest extends FreeSpec with Matchers with ScalatestRouteTest {
val get = HttpRequest(HttpMethods.GET, uri = "/myurl?var1=456&var2=123&var3=789&var4=987")
.withEntity("sessionid:1234567890")
.withHeaders(
scala.collection.immutable.Seq(
RawHeader("Content-Type", "application/x-www-form-urlencoded"), // same problem if I comment out these 2 Content-Type lines
RawHeader("Content-Type", "multipart/form-data"),
RawHeader("Accept", "Application/JSON")
)
)
get ~> route ~> check {
status should equal(StatusCodes.OK)
}
The exception is thrown before the formField line.
Full exception:
ScalaTestFailureLocation: akka.http.scaladsl.testkit.RouteTest$$anonfun$check$1 at (RouteTest.scala:57)
org.scalatest.exceptions.TestFailedException: Request was rejected with rejection UnsupportedRequestContentTypeRejection(Set(application/x-www-form-urlencoded, multipart/form-data))
at akka.http.scaladsl.testkit.TestFrameworkInterface$Scalatest$class.failTest(TestFrameworkInterface.scala:24)
}
You could either use:
val get = HttpRequest(HttpMethods.GET, uri = "/myurl?var1=456&var2=123&var3=789&var4=987", entity = FormData("sessionid" -> "1234567.890").toEntity)
or
val get = Get("/myurl?var1=456&var2=123&var3=789&var4=987", FormData("sessionid" -> "1234567.890"))

Why Akka Http Client Throws an Exception on Any Other from Successful Response Status?

I am using Akka Http (v. 10.1.10) to create a client with proxy.
Each time the response is any other than successful, I get an error instead of a proper response entity:
akka.http.impl.engine.client.ProxyConnectionFailedException: The HTTP(S) proxy rejected to open a connection to hahahahahhahaahahhahaadsfsd.com:80 with status code: 503 Service Unavailable
at akka.http.impl.engine.client.HttpsProxyGraphStage$$anon$1$$anon$4.onPush(HttpsProxyGraphStage.scala:143)
at akka.stream.impl.fusing.GraphInterpreter.processPush(GraphInterpreter.scala:523)
at akka.stream.impl.fusing.GraphInterpreter.execute(GraphInterpreter.scala:409)
at akka.stream.impl.fusing.GraphInterpreterShell.runBatch(ActorGraphInterpreter.scala:606)
at akka.stream.impl.fusing.GraphInterpreterShell$AsyncInput.execute(ActorGraphInterpreter.scala:485)
at akka.stream.impl.fusing.GraphInterpreterShell.processEvent(ActorGraphInterpreter.scala:581)
at akka.stream.impl.fusing.ActorGraphInterpreter.akka$stream$impl$fusing$ActorGraphInterpreter$$processEvent(ActorGraphInterpreter.scala:749)
at akka.stream.impl.fusing.ActorGraphInterpreter$$anonfun$receive$1.applyOrElse(ActorGraphInterpreter.scala:764)
at akka.actor.Actor.aroundReceive(Actor.scala:539)
at akka.actor.Actor.aroundReceive$(Actor.scala:537)
at akka.stream.impl.fusing.ActorGraphInterpreter.aroundReceive(ActorGraphInterpreter.scala:671)
at akka.actor.ActorCell.receiveMessage(ActorCell.scala:612)
at akka.actor.ActorCell.invoke(ActorCell.scala:581)
at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:268)
at akka.dispatch.Mailbox.run(Mailbox.scala:229)
at akka.dispatch.Mailbox.exec(Mailbox.scala:241)
at akka.dispatch.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
at akka.dispatch.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
at akka.dispatch.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
at akka.dispatch.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
In the Akka Http core code, I found that it is the implementation of the handler for proxy that forces the error on purpose if the response is any other than successful:
case Connecting =>
val proxyResponse = grab(bytesIn)
parser.parseBytes(proxyResponse) match {
case NeedMoreData =>
pull(bytesIn)
case ResponseStart(_: StatusCodes.Success, _, _, _, _) =>
var pushed = false
val parseResult = parser.onPull()
require(parseResult == ParserOutput.MessageEnd, s"parseResult should be MessageEnd but was $parseResult")
parser.onPull() match {
// NeedMoreData is what we emit in overridden `parseMessage` in case input.size == offset
case NeedMoreData =>
case RemainingBytes(bytes) =>
push(sslOut, bytes) // parser already read more than expected, forward that data directly
pushed = true
case other =>
throw new IllegalStateException(s"unexpected element of type ${other.getClass}")
}
parser.onUpstreamFinish()
log.debug(s"HTTP(S) proxy connection to {}:{} established. Now forwarding data.", targetHostName, targetPort)
state = Connected
if (isAvailable(bytesOut)) pull(sslIn)
if (isAvailable(sslOut)) pull(bytesIn)
case ResponseStart(statusCode, _, _, _, _) =>
failStage(new ProxyConnectionFailedException(s"The HTTP(S) proxy rejected to open a connection to $targetHostName:$targetPort with status code: $statusCode"))
case other =>
throw new IllegalStateException(s"unexpected element of type $other")
}
I am wondering what is the reason for such implementation, if someone knows? And how to work it around to get a response entity instead of the error when response from the server is not successful?
Try recover function to capture and return response entity you want.
Http().singleRequest(HttpRequest(
uri = url
)).map(response => {
response
}) recover {
case e: Exception => {
e.printStackTrace()
// anything you want to return
HttpResponse(StatusCodes.OK)
}
}

How to handle UndeliverableException error thrown via blockingFirst() in Micronaut?

Below is a snippet from my micronaut web service:
try {
val result = hClient.exchange(GET<String>("$readEndpoint/$token")).blockingFirst()
logger.error("result")
} catch (e: Exception) {
logger.error(e.message)
}
hClient is a reactive http client injected as #Inject val hClient: RxHttpClient
The endpoint is throwing "Connection reset by peer" exception.
Issue I am facing
Even though I have wrapped code in try and catch, An exception io.reactivex.exceptions.UndeliverableException is thrown and not caught.
I basically get two exceptions thrown, one is caught by catch block with message Error occurred reading HTTP response: Connection reset by peer, another one is flowing up to service with message io.reactivex.exceptions.UndeliverableException: The exception could not be delivered to the consumer because it has already canceled/disposed the flow or the exception has nowhere to go to begin with. Further reading: https://github.com/ReactiveX/RxJava/wiki/What's-different-in-2.0#error-handling | java.nio.channels.ClosedChannelException
Reproducible via below code
Keep timeout too less to receive a timeout error.
micronaut:
http:
client:
read-timeout: 1s
#Controller("/")
class TokenController(
#Client("https://hello123456789.com/dummy") #Inject val hClient: RxHttpClient
) {
#Get("/test")
fun refresh(): String {
try {
val result = hClient.exchange(HttpRequest.GET<String>("/token/1234")).blockingFirst()
println("result")
} catch (e: Exception) {
println(e.message)
}
return ""
}
}
Googling told me that I need to add global onError to rxjava but couldn't find how to do that in Micronaut.
Any help is appreciated.

Terminate Observable by timeout

I'm trying to limit life of observable by timeout:
def doLongOperation() = {
Thread.sleep(duration)
"OK"
}
def firstStep = Observable.create(
(observer: Observer[String]) => {
observer.onNext(doLongOperation())
observer.onCompleted()
Subscription()
}
)
firstStep
.timeout(1 second)
.subscribe(
item => println(item),
throwable => throw throwable,
() => println("complete")
)
I would like to distinguish between following results:
Observable finished by timeout, no result obtained
Exception thrown during execution
Execution finished successfully, return value
I can process cases 2 and 3 with no problem in partials onNext and onError, but how do I detect if observable finished by timeout?
One more thing: I've never get into block onComplete, though there is a call to obeserver.onCompleted() in my code. Why?
If a timeout happens, that TimeoutException is emitted on the computation thread where a throw throwable is ends up being ignored and your main thread won't and can't see it. You can add toBlocking after the timeout so any exception will end up on the same thread:
firstStep
.timeout(1 second)
.toBlocking()
.subscribe(
item => println(item),
throwable => println(throwable),
() => println("complete")
)
TimeoutException gets thrown indeed. The problem was caused by using wrong libraries. I had "com.netflix.rxjava" in my dependencies, instead of "io.reactivex"