add in support for apollo federation

guardian · Jan 31, 2025 · d312aa7 · d312aa7
1 parent 2ae4ead
commit d312aa7
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Showing 5 changed files with 47 additions and 5 deletions.
diff --git a/build.sbt b/build.sbt
@@ -46,9 +46,10 @@ lazy val root = (project in file("."))
       "org.http4s" %% "http4s-core" % "0.23.21",
       "org.http4s" %% "http4s-dsl" % "0.23.21",
       "org.http4s" %% "http4s-ember-server" % "0.23.21",
-      "org.sangria-graphql" %% "sangria" % "4.0.1",
+      "org.sangria-graphql" %% "sangria" % "4.1.1",
       "org.sangria-graphql" %% "sangria-circe" % "1.3.2",
-      "io.circe" %% "circe-core" % "0.14.5",
+      "org.sangria-graphql" %% "sangria-federated" % "0.8.1",
+      "io.circe" %% "circe-core" % "0.14.9",
       "io.circe" %% "circe-parser" % "0.14.5",
       "io.circe" %% "circe-generic" % "0.14.5",
       "io.circe" %% "circe-optics" % "0.14.1",

diff --git a/src/main/scala/GraphQLServer.scala b/src/main/scala/GraphQLServer.scala
@@ -32,6 +32,7 @@ class GraphQLServer(documentRepo:DocumentRepo) {
     IO.fromFuture(
       IO {
         val context = GQLQueryContext(documentRepo, tier)
+        //FIXME - add in variables here
         Executor.execute(inUseSchema, doc, middleware = permissions :: metrics :: Nil, userContext = context).map(_.asJson.noSpaces)
       }
     )

diff --git a/src/main/scala/Main.scala b/src/main/scala/Main.scala
@@ -1,6 +1,6 @@
 import cats.effect._
 import com.comcast.ip4s.{IpLiteralSyntax, Ipv4Address, Ipv6Address}
-import datastore.ElasticsearchRepo
+import datastore.{ElasticsearchRepo, GQLQueryContext}
 import io.prometheus.client.hotspot.DefaultExports
 import org.http4s._
 import org.http4s.dsl.io._
@@ -10,6 +10,10 @@ import org.http4s.implicits._
 import org.slf4j.LoggerFactory
 import security.{ApiKeyAuth, DeveloperTier, InternalTier, Security, UserTier}
 import internalmetrics.PrometheusMetrics
+import io.circe.Json
+import org.http4s.headers.Server
+import sangria.federation.v2.Federation
+import sangria.schema.Schema
 
 import scala.concurrent.duration._
 import utils.Config.fetchConfig
@@ -64,6 +68,11 @@ object Main extends IOApp {
       }
   }
 
+//  private def graphQL[F[_]: Async]: GraphQL[F, GQLQueryContext] = {
+//    val (schema, um) = Federation.federate[GQLQueryContext, Any, Json](
+//      Schema
+//    )
+//  }
   def run(args:List[String]):IO[ExitCode] = {
     val httpApp = Router("/" -> graphqlService).orNotFound
     logger.info("Starting up on 0.0.0.0 port 9000")
@@ -77,5 +86,10 @@ object Main extends IOApp {
       .build
       .use(_=>IO.never)
       .as(ExitCode.Success)
+//    Server.resource[IO, GQLQueryContext](
+//      logger,
+//      graphQL,
+//      port"9000"
+//    ).use()
   }
 }
diff --git a/src/main/scala/com/gu/contentapi/porter/graphql/Content.scala b/src/main/scala/com/gu/contentapi/porter/graphql/Content.scala
@@ -8,6 +8,8 @@ import io.circe.generic.auto._
 import io.circe.syntax._
 import com.gu.contentapi.porter.model
 import datastore.GQLQueryContext
+import sangria.execution.deferred.HasId
+import sangria.federation.v2.Directives
 import sangria.macros.derive
 import security.{InternalTier, RightsManagedTier}
 
@@ -163,6 +165,7 @@ object Content {
         }
       )
     )
-  )
+  ).withDirective(Directives.Key("id"))
 
+  implicit val ContentHasId:HasId[model.Content, String] = HasId(_.id)
 }
diff --git a/src/main/scala/com/gu/contentapi/porter/graphql/RootQuery.scala b/src/main/scala/com/gu/contentapi/porter/graphql/RootQuery.scala
@@ -9,7 +9,10 @@ import io.circe.Json
 
 import scala.concurrent.ExecutionContext.Implicits.global
 import io.circe.generic.auto._
+import io.circe.generic.semiauto.deriveDecoder
 import org.slf4j.LoggerFactory
+import sangria.execution.deferred.Fetcher
+import sangria.federation.v2.{Directives, EntityResolver, Federation}
 
 import scala.concurrent.Future
 
@@ -128,5 +131,25 @@ object RootQuery {
     )
   )
 
-  val schema = Schema(Query)
+  //For graphQL Federeation
+  import com.gu.contentapi.porter.graphql.Content.ContentHasId
+  case class StateArg(id: String)
+  val articles: Fetcher[GQLQueryContext, Content, Content, String] = Fetcher {
+    (ctx, ids) => Future.sequence(
+        ids.map(id=>ctx.repo.docById(id).map(_.map(contentTransform))
+        .map(_.nodes.headOption))
+    ).map(_.collect({case Some(content)=>content}))
+  }
+
+  implicit val decoder: sangria.federation.v2.Decoder[Json, StateArg] = deriveDecoder[StateArg].decodeJson(_)
+  private val articleStateResolver = EntityResolver[GQLQueryContext, Json, Content, StateArg](
+    __typeName = Content.getClass.getTypeName,
+    (arg, _) => articles.deferOpt(arg.id)
+  )
+
+  val (schema, um) = Federation.federate[GQLQueryContext, Unit, Json](
+    Schema(Query),
+    sangria.marshalling.circe.CirceInputUnmarshaller,
+    articleStateResolver
+  )
 }