Support configurable paths prefixes for Connect routes (#40)

Author: igor-vovk

core/src/main/scala/org/ivovk/connect_rpc_scala/ConnectRouteBuilder.scala

@@ -5,7 +5,7 @@ import cats.effect.{Async, Resource}
 import cats.implicits.*
 import io.grpc.{ManagedChannelBuilder, ServerBuilder, ServerServiceDefinition}
 import org.http4s.dsl.Http4sDsl
-import org.http4s.{HttpApp, HttpRoutes, Method}
+import org.http4s.{HttpApp, HttpRoutes, Method, Uri}
 import org.ivovk.connect_rpc_scala.grpc.*
 import org.ivovk.connect_rpc_scala.http.*
 import org.ivovk.connect_rpc_scala.http.QueryParams.*
@@ -35,6 +35,7 @@ case class ConnectRouteBuilder[F[_] : Async] private(
   jsonPrinterConfigurator: Endo[Printer] = identity,
   serverConfigurator: Endo[ServerBuilder[_]] = identity,
   channelConfigurator: Endo[ManagedChannelBuilder[_]] = identity,
+  pathPrefix: Uri.Path = Uri.Path.Root,
   executor: Executor = ExecutionContext.global,
   waitForShutdown: Duration = 5.seconds,
   treatTrailersAsHeaders: Boolean = true,
@@ -51,6 +52,9 @@ case class ConnectRouteBuilder[F[_] : Async] private(
   def withChannelConfigurator(method: Endo[ManagedChannelBuilder[_]]): ConnectRouteBuilder[F] =
     copy(channelConfigurator = method)
 
+  def withPathPrefix(path: Uri.Path): ConnectRouteBuilder[F] =
+    copy(pathPrefix = path)
+
   def withExecutor(executor: Executor): ConnectRouteBuilder[F] =
     copy(executor = executor)
 
@@ -106,12 +110,12 @@ case class ConnectRouteBuilder[F[_] : Async] private(
       )
 
       HttpRoutes.of[F] {
-        case req@Method.GET -> Root / serviceName / methodName :? EncodingQP(contentType) +& MessageQP(message) =>
+        case req@Method.GET -> pathPrefix / serviceName / methodName :? EncodingQP(contentType) +& MessageQP(message) =>
           val grpcMethod = MethodName(serviceName, methodName)
           val entity     = RequestEntity[F](message, req.headers)
 
           handler.handle(Method.GET, contentType.some, entity, grpcMethod)
-        case req@Method.POST -> Root / serviceName / methodName =>
+        case req@Method.POST -> pathPrefix / serviceName / methodName =>
           val grpcMethod  = MethodName(serviceName, methodName)
           val contentType = req.contentType.map(_.mediaType)
           val entity      = RequestEntity[F](req)

core/src/test/scala/org/ivovk/connect_rpc_scala/HttpTest.scala

@@ -90,4 +90,30 @@ class HttpTest extends AnyFunSuite, Matchers {
       .unsafeRunSync()
   }
 
+  test("support path prefixes") {
+    val service = TestService.bindService(TestServiceImpl, ExecutionContext.global)
+
+    ConnectRouteBuilder.forService[IO](service)
+      .withPathPrefix(Root / "connect")
+      .build
+      .flatMap { app =>
+        val client = Client.fromHttpApp(app)
+
+        client.run(
+          Request[IO](Method.POST, uri"/connect/org.ivovk.connect_rpc_scala.test.TestService/Add")
+            .withEntity(""" { "a": 1, "b": 2} """)
+        )
+      }
+      .use { response =>
+        for {
+          body <- response.as[String]
+          status <- response.status.pure[IO]
+        } yield {
+          assert(body == """{"sum":3}""")
+          assert(status == Status.Ok)
+        }
+      }
+      .unsafeRunSync()
+  }
+
 }