I am trying to use the library Op-Rabbit to consume a RabbitMQ queue in an Akka-Http project.
I want to use Spray-Json for the marshalling/ un marshalling.
import com.spingo.op_rabbit.SprayJsonSupport._
import com.spingo.op_rabbit.stream.RabbitSource
import com.spingo.op_rabbit.{Directives, RabbitControl}
object Boot extends App with Config with BootedCore with ApiService {
this: ApiService with Core =>
implicit val materializer = ActorMaterializer()
Http().bindAndHandle(routes, httpInterface, httpPort)
log.info("Http Server started")
implicit val rabbitControl = system.actorOf(Props[RabbitControl])
import Directives._
RabbitSource(
rabbitControl,
channel(qos = 3),
consume(queue(
"such-queue",
durable = true,
exclusive = false,
autoDelete = false)),
body(as[User])).
runForeach { user =>
log.info(user)
} // after each successful iteration the message is acknowledged.
}
In a separate file:
case class User(id: Long,name: String)
object JsonFormat extends DefaultJsonProtocol {
implicit val format = jsonFormat2(User)
}
The error I am getting is:
could not find implicit value for parameter um: akka.http.scaladsl.unmarshalling.FromRequestUnmarshaller[*.*.models.User]
[error] body(as[User])). // marshalling is automatically hooked up using implicits
[error] ^
[error]could not find implicit value for parameter um: com.spingo.op_rabbit.RabbitUnmarshaller[*.*.models.User]
[error] body(as[User])
[error] ^
[error] two errors found
Im not sure how to get the op-rabbit spray-json support working properly.
Thanks for any help.
Try to provide an implicit marshaller for your User class like they do it for Int (in RabbitTestHelpers.scala):
implicit val simpleIntMarshaller = new RabbitMarshaller[Int] with RabbitUnmarshaller[Int] {
val contentType = "text/plain"
val contentEncoding = Some("UTF-8")
def marshall(value: Int) =
value.toString.getBytes
def unmarshall(value: Array[Byte], contentType: Option[String], charset: Option[String]) = {
new String(value).toInt
}
}
Related
I have the following:
Account.scala
package modules.accounts
import java.time.Instant
import reactivemongo.api.bson._
case class Account(id: String, name: String)
object Account {
type ID = String
implicit val accountHandler: BSONDocumentHandler[Account] = Macros.handler[Account]
// implicit def accountWriter: BSONDocumentWriter[Account] = Macros.writer[Account]
// implicit def accountReader: BSONDocumentReader[Account] = Macros.reader[Account]
}
AccountRepo.scala
package modules.accounts
import java.time.Instant
import reactivemongo.api.collections.bson.BSONCollection
import scala.concurrent.ExecutionContext
final class AccountRepo(
val coll: BSONCollection
)(implicit ec: ExecutionContext) {
import Account.{ accountHandler, ID }
def insertTest() = {
val doc = Account(s"account123", "accountName") //, Instant.now)
coll.insert.one(doc)
}
}
The error I am getting is:
could not find implicit value for parameter writer: AccountRepo.this.coll.pack.Writer[modules.accounts.Account]
[error] coll.insert.one(doc)
From what I understand the implicit handler that is generated by the macro should be enough and create the Writer. What am I doing wrong?
Reference: http://reactivemongo.org/releases/1.0/documentation/bson/typeclasses.html
The code is mismixing different versions.
The macro generated handler is using the new BSON API, as it can be seen with the import reactivemongo.api.bson, whereas the collection is using an old driver, as it can be seen as it uses reactivemongo.api.collections.bson instead of reactivemongo.api.bson.collection.
It's recommended to have a look at the documentation, and not mixing incompatible versions of related libraries.
I would like to write a simple test for a controller, which accepts a json body. But as soon I add the parse.json BodyParser to the Action my Tests cannot be compiled anymore.
The Setup is basically the plain play-scala-seed project.
Error:
[error] ... could not find implicit value for parameter mat: akka.stream.Materializer
[error] status(home) mustBe OK
[error] ^
HomeController:
def index() = Action { implicit request =>
Ok
}
def json() = Action(parse.json) { implicit request =>
Ok
}
HomeControllerSpec:
class HomeControllerSpec extends PlaySpec with GuiceOneAppPerTest with Injecting {
"HomeController POST" should {
"answer Ok" in {
val controller = new HomeController(stubControllerComponents())
val home = controller.json().apply(FakeRequest(POST, "/"))
status(home) mustBe OK
}
}
There seem to be two issues with the code in question regarding stubControllerComponents and FakeRequest calls.
Helpers.stubControllerComponents by default constructs ControllerComponents with NoMaterializer which simply throws an exception when used, so we need to provide an actual materializer as follows:
implicit val materializer = ActorMaterializer()(ActorSystem())
Helpers.stubControllerComponents(
playBodyParsers = Helpers.stubPlayBodyParsers(materializer)
)
The second issue is with FakeRequest where we need to provide a body as follows (otherwise we get 4xx error) :
FakeRequest(POST, "/json").withBody(Json.obj("name" -> "Jon Doe"))
Taking into account the above we can write the complete test as follows:
class HomeControllerSpec extends PlaySpec with GuiceOneAppPerTest {
"HomeController POST" should {
"answer Ok" in {
implicit val materializer = ActorMaterializer()(ActorSystem())
val controllerComponents =
Helpers.stubControllerComponents(
playBodyParsers = Helpers.stubPlayBodyParsers(materializer)
)
val controller = new HomeController(controllerComponents)
val fakeRequest =
FakeRequest(POST, "/json").withBody(Json.obj("name" -> "Jon Doe"))
val home = call(controller.json(), fakeRequest)
status(home) mustBe OK
}
}
}
It seems that you need to inject a materializer in your controller:
class Controller #Inject() (implicit val mat: Materializer) { ??? }
I am attempting to create a unmarshaller for akka http, going from avro to a custom case class. But it gives me a very vague error: "could not find implicit value". How can I debug this or make scala give me hint where the problem is?
I set up the route as such:
class MetricsRoute(implicit val system: ActorSystem, implicit val materializer: ActorMaterializer) {
import system.dispatcher
def getRoute() = {
path("metrics") {
put {
decodeRequest {
entity(as[Metrics]) { metrics: Metrics =>
println(metrics.time)
complete(HttpEntity(ContentTypes.`text/html(UTF-8)`, "<h1>hi!</h1>"))
}
}
}
}
}
In the same class I also created the unmarshaller like this:
implicit def avroUnmarshaller(): FromRequestUnmarshaller[Metrics] =
Unmarshaller.withMaterializer {
implicit ex: ExecutionContext =>
implicit mat: Materializer =>
request: HttpRequest => {
val inputStream = request.entity.dataBytes.runWith(
StreamConverters.asInputStream(FiniteDuration(3, TimeUnit.SECONDS))
)
val reader = new SpecificDatumReader[AvroMetrics](classOf[AvroMetrics])
val decoder:BinaryDecoder = DecoderFactory.get().binaryDecoder(inputStream, null)
//AvroMetrics is a case class generated from the avro schema
val avroMetrics:AvroMetrics = AvroMetrics(0, 0, List())
reader.read(avroMetrics, decoder)
Future {
//converts the avro case class to the case class specific for my application
convertMetrics(avroMetrics)
}
}
}
But this gives me the very vague 'could not find implicit value' error:
[error] /mypath/MetricsRoute.scala:34: could not find implicit value for parameter um: akka.http.scaladsl.unmarshalling.FromRequestUnmarshaller[my.package.types.Metrics]
[error] entity(as[Metrics]) { metrics: Metrics =>
[error] ^
[error] one error found
[error] (compile:compileIncremental) Compilation failed
How do I go about debugging what is missing or what I did wrong?
Edit:
Worth noting is when I specify the unmarshaller myself it does work, so changing
entity(as[Metrics]) { metrics: Metrics =>
to
entity(avroUnmarshaller) { metrics: Metrics =>
Which seems to indicate the marshaller code itself isn't wrong, but I've done something wrong with the types?
The compiler is looking for a FromRequestUnmarshaller[Metrics], what you defined is of type () => FromRequestUnmarshaller[Metrics].
Try defining your implicit with no empty braces, e.g.
implicit def avroUnmarshaller: FromRequestUnmarshaller[Metrics] = ???
instead of
implicit def avroUnmarshaller(): FromRequestUnmarshaller[Metrics] = ???
(also, it could be made a val, but that's not relevant to this issue)
This is my code for the server written using Akka framework:
case class Sentence(data: String)
case class RawTriples(triples: List[String])
trait Protocols extends DefaultJsonProtocol {
implicit val sentenceRequestFormat = jsonFormat1(Sentence)
implicit val rawTriplesFormat = jsonFormat1(RawTriples)
}
trait Service extends Protocols {
implicit val system: ActorSystem
implicit def executor: ExecutionContextExecutor
implicit val materializer: Materializer
val openie = new OpenIE
def config: Config
val logger: LoggingAdapter
lazy val ipApiConnectionFlow: Flow[HttpRequest, HttpResponse, Any] =
Http().outgoingConnection(config.getString("services.ip-api.host"), config.getInt("services.ip-api.port"))
def ipApiRequest(request: HttpRequest): Future[HttpResponse] = Source.single(request).via(ipApiConnectionFlow).runWith(Sink.head)
val routes = {
logRequestResult("akka-http-microservice") {
pathPrefix("openie") {
post {
decodeRequest{
entity(as[Sentence]){ sentence =>
complete {
var rawTriples = openie.extract(sentence.data)
val resp: MutableList[String] = MutableList()
for(rtrip <- rawTriples){
resp += (rtrip.toString())
}
val response: List[String] = resp.toList
println(response)
response
}
}
}
}
}
}
}
}
object AkkaHttpMicroservice extends App with Service {
override implicit val system = ActorSystem()
override implicit val executor = system.dispatcher
override implicit val materializer = ActorMaterializer()
override val config = ConfigFactory.load()
override val logger = Logging(system, getClass)
Http().bindAndHandle(routes, config.getString("http.interface"), config.getInt("http.port"))
}
The server accepts a POST request containing a sentence and returns a json array in return. It works fine but if I am making requests to it too frequently using parallelized code, then it gives 500 Internal server error. I wanted to know is there any parameter which I can set in the server to avoid that (number of ready threads for accepting requests etc).
In log files, the error is logged as:
[ERROR] [05/31/2017 11:48:38.110]
[default-akka.actor.default-dispatcher-6]
[akka.actor.ActorSystemImpl(default)] Error during processing of
request: 'null'. Completing with 500 Internal Server Error response.
The doc on the bindAndHandle method shows what you want:
/**
* Convenience method which starts a new HTTP server at the given endpoint and uses the given `handler`
* [[akka.stream.scaladsl.Flow]] for processing all incoming connections.
*
* The number of concurrently accepted connections can be configured by overriding
* the `akka.http.server.max-connections` setting. Please see the documentation in the reference.conf for more
* information about what kind of guarantees to expect.
*
* To configure additional settings for a server started using this method,
* use the `akka.http.server` config section or pass in a [[akka.http.scaladsl.settings.ServerSettings]] explicitly.
*/
akka.http.server.max-connections is probably what you want. As the doc suggests, you can also dig deeper into the akka.http.server config section.
Add following in application.conf file
akka.http {
server {
server-header = akka-http/${akka.http.version}
idle-timeout = infinite
request-timeout = infinite
}
}
I'm trying to perform a simple json post with spray. But it seems that i can get an http entity for a json object that can be Marshall.
here is my error:
[error]
...../IdeaProjects/PoolpartyConnector/src/main/scala/org/iadb/poolpartyconnector/thesaurusoperation/ThesaurusCacheService.scala:172:
could not find implicit value for evidence parameter of type
spray.httpx.marshalling.Marshaller[spray.json.JsValue]
[error] val request =
Post(s"$thesaurusapiEndpoint/$coreProjectId/suggestFreeConcept?",
suggestionJsonBody)
and the code that comes with it:
override def createSuggestedFreeConcept(suggestedPrefLabel: String, lang: String, scheme: String, b: Boolean): String = {
import system.dispatcher
import spray.json._
val pipeline = addCredentials(BasicHttpCredentials("superadmin", "poolparty")) ~> sendReceive
val label = LanguageLiteral(suggestedPrefLabel, lang)
val suggestion = SuggestFreeConcept(List(label), b, Some(List(scheme)), None, None,None, None)
val suggestionJsonBody = suggestion.toJson
val request = Post(s"$thesaurusapiEndpoint/$coreProjectId/suggestFreeConcept?", suggestionJsonBody)
val res = pipeline(request)
getSuggestedFromFutureHttpResponse(res) match {
case None => ""
case Some(e) => e
}
}
Please, does any one has an idea of what is going on with the implicit marshaller. I though spray Json would come with implicit marshaller.
I assume you already have a custom Json Protocol somewhere so that suggestion.toJson works correctly?
Try the following:
val body = HttpEntity(`application/json`, suggestionJsonBody.prettyPrint)
val request = Post(s"$thesaurusapiEndpoint/$coreProjectId/suggestFreeConcept?", body)
you could also use compactPrint rather than prettyPrint, in either case, it turns the Json into a string containing the json information.
Here is how i solved it:
override def createSuggestedFreeConcepts(suggestedPrefLabels: List[LanguageLiteral], scheme: String, checkDuplicates: Boolean): List[String] = {
import system.dispatcher
import spray.httpx.marshalling._
import spray.httpx.SprayJsonSupport._
val pipeline = addCredentials(BasicHttpCredentials("superadmin", "poolparty")) ~> sendReceive
suggestedPrefLabels map { suggestedPrefLabel =>
val suggestion = SuggestFreeConcept(List(suggestedPrefLabel), checkDuplicates, Some(List(Uri(scheme))), None, None, None, None)
val request = Post(s"$thesaurusapiEndpoint/$coreProjectId/suggestFreeConcept", marshal(suggestion))
val res = pipeline(request)
getSuggestedFromFutureHttpResponse(res) match {
case None => ""
case Some(e) => e
}
}
}
the key is:
import spray.httpx.marshalling._ import spray.httpx.SprayJsonSupport._
and
val request =
Post(s"$thesaurusapiEndpoint/$coreProjectId/suggestFreeConcept",
marshal(suggestion))
I marshall suggestion. The explanation is not super super straightforward. But by fetching around in the doc, it is explained.