rustedbones / akka-http-avro

akka-http avro marshalling/unmarshalling for generated java avro specific records

Version Matrix

akka-http-avro

Scala CI Maven Central Software License

akka-http avro marshalling/unmarshalling for generated java avro specific records

Versions

Version Release date Akka Http version Avro version Scala versions
0.1.2 2020-09-18 10.2.0 1.10.0 2.13.3, 2.12.12
0.1.1 2020-07-03 10.1.12 1.10.0 2.13.3, 2.12.11, 2.11.12
0.1.0 2020-03-01 10.1.11 1.9.2 2.13.1, 2.12.10, 2.11.12

The complete list can be found in the CHANGELOG file.

Getting akka-http-avro

Libraries are published to Maven Central. Add to your build.sbt:

libraryDependencies += "fr.davit" %% "akka-http-avro" % <version>

Quick start

For the examples, we are using the following avro domain model

{
  "namespace": "com.example",
  "type": "record",
  "name": "Item",
  "fields": [
    {
      "name": "name",
      "type": "string"
    },
    {
      "name": "id",
      "type": "long"
    }
  ]
}

and

{
  "namespace": "com.example",
  "type": "record",
  "name": "Order",
  "fields": [
    {
      "name": "items",
      "type": {
        "type" : "array",
        "items": "com.example.Item"
      }
    }
  ]
}

Marshalling/Unmarshalling of the generated classes depends on the Accept/Content-Type header sent by the client:

  • Content-Type: application/json: json
  • Content-Type: avro/binary: binary

-No Accept header or matching several (eg Accept: application/*) will take the 1st matching type from the above list.

Avro

The implicit marshallers and unmarshallers for your generated avro classes are defined in AvroSupport. Specific (un)marshallers can be imported from AvroBinarySupport, AvroJsonSupport. You simply need to have them in scope.

import akka.http.scaladsl.server.Directives._
import fr.davit.akka.http.scaladsl.marshallers.avro.AvroSupport._


object MyAvroService {

  val route =
    get {
      pathSingleSlash {
        complete(Item.newBuilder().setName("thing").setId(42).build())
      }
    } ~ post {
      entity(as[Order]) { order =>
        val itemsCount = order.getItems.size
        val itemNames = order.getItems.asScala.map(_.getName).mkString(", ")
        complete(s"Ordered $itemsCount items: $itemNames")
      }
    }
}

Limitation

Entity streaming (http chunked transfer) is at the moment not supported by the library.