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author | Zach Smith <zach@driver.xyz> | 2018-03-16 18:47:30 +0100 |
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committer | Zach Smith <zach@driver.xyz> | 2018-03-16 20:03:44 +0100 |
commit | ce099ac3ba85f71adeba0bb8398b69dc7cd2e8d1 (patch) | |
tree | 772e000647aeaf59bd8b22cd22661d3998f22f7e /src/main/scala/xyz/driver/core/rest/PatchSupport.scala | |
parent | 96aa1fbf7608e3b9cd1ba06c57ab1f356409733d (diff) | |
download | driver-core-ce099ac3ba85f71adeba0bb8398b69dc7cd2e8d1.tar.gz driver-core-ce099ac3ba85f71adeba0bb8398b69dc7cd2e8d1.tar.bz2 driver-core-ce099ac3ba85f71adeba0bb8398b69dc7cd2e8d1.zip |
Add PatchSupport trait and tests
Diffstat (limited to 'src/main/scala/xyz/driver/core/rest/PatchSupport.scala')
-rw-r--r-- | src/main/scala/xyz/driver/core/rest/PatchSupport.scala | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/src/main/scala/xyz/driver/core/rest/PatchSupport.scala b/src/main/scala/xyz/driver/core/rest/PatchSupport.scala new file mode 100644 index 0000000..5fd9149 --- /dev/null +++ b/src/main/scala/xyz/driver/core/rest/PatchSupport.scala @@ -0,0 +1,81 @@ +package xyz.driver.core.rest + +import akka.http.javadsl.server.Rejections +import akka.http.scaladsl.marshallers.sprayjson.SprayJsonSupport +import akka.http.scaladsl.server.{Directive, Directive1, Directives, Route} +import spray.json._ +import xyz.driver.core.Id + +import scala.concurrent.Future + +trait PatchSupport extends Directives with SprayJsonSupport { + + trait PatchRetrievable[T] { + def apply(id: Id[T]): Future[Option[T]] + } + + protected def mergeObjects(oldObj: JsObject, newObj: JsObject, maxLevels: Option[Int] = None): JsObject = { + JsObject(oldObj.fields.map({ + case (key, oldValue) => + val newValue = newObj.fields.get(key).fold(oldValue)(mergeJsValues(oldValue, _, maxLevels.map(_ - 1))) + key -> newValue + })(collection.breakOut): _*) + } + + protected def mergeJsValues(oldValue: JsValue, newValue: JsValue, maxLevels: Option[Int] = None): JsValue = { + def mergeError(typ: String): Nothing = + deserializationError(s"Expected $typ value, got $newValue") + + if (maxLevels.exists(_ < 0)) oldValue + else { + (oldValue, newValue) match { + case (_: JsString, newString @ (JsString(_) | JsNull)) => newString + case (_: JsString, _) => mergeError("string") + case (_: JsNumber, newNumber @ (JsNumber(_) | JsNull)) => newNumber + case (_: JsNumber, _) => mergeError("number") + case (_: JsBoolean, newBool @ (JsBoolean(_) | JsNull)) => newBool + case (_: JsBoolean, _) => mergeError("boolean") + case (_: JsArray, newArr @ (JsArray(_) | JsNull)) => newArr + case (_: JsArray, _) => mergeError("array") + case (oldObj: JsObject, newObj: JsObject) => mergeObjects(oldObj, newObj) + case (_: JsObject, JsNull) => JsNull + case (_: JsObject, _) => mergeError("object") + case (JsNull, _) => newValue + } + } + } + + def as[T]( + implicit patchable: PatchRetrievable[T], + jsonFormat: RootJsonFormat[T]): (PatchRetrievable[T], RootJsonFormat[T]) = + (patchable, jsonFormat) + + def patch[T](patchable: (PatchRetrievable[T], RootJsonFormat[T]), id: Id[T]): Directive1[T] = Directive { + inner => requestCtx => + import requestCtx.executionContext + val retriever = patchable._1 + implicit val jsonFormat: RootJsonFormat[T] = patchable._2 + Directives.patch { + entity(as[JsValue]) { newValue => + onSuccess(retriever(id).map(_.map(_.toJson))) { + case Some(oldValue) => + val mergedObj = mergeJsValues(oldValue, newValue) + util + .Try(mergedObj.convertTo[T]) + .transform[Route]( + mergedT => util.Success(inner(Tuple1(mergedT))), { + case jsonException: DeserializationException => + util.Success(reject(Rejections.malformedRequestContent(jsonException.getMessage, jsonException))) + case t => util.Failure(t) + } + ) + .get // intentionally re-throw all other errors + case None => + reject() + } + } + }(requestCtx) + } +} + +object PatchSupport extends PatchSupport |