Allow BaseUrl override in plugins

.vscode/launch.json

@@ -13,7 +13,7 @@
         "${workspaceFolder}/vscode-extension/out/*.js",
         "${workspaceFolder}/vscode-extension/out/*.js.map"
       ],
-      "preLaunchTask": "build",
+      // "preLaunchTask": "build",
       "request": "launch",
       "type": "extensionHost",
       "sourceMaps": true

modules/lsp/src/main/scala/playground/lsp/LanguageClient.scala

@@ -9,6 +9,7 @@ import cats.tagless.FunctorK
 import cats.tagless.implicits.*
 import cats.~>
 import com.google.gson.JsonElement
+import io.circe.Json
 import org.eclipse.lsp4j.ConfigurationItem
 import org.eclipse.lsp4j.ConfigurationParams
 import org.eclipse.lsp4j.MessageParams
@@ -23,7 +24,7 @@ trait LanguageClient[F[_]] extends Feedback[F] {
 
   def configuration[A](
     v: ConfigurationValue[A]
-  ): F[A]
+  ): F[Option[A]]
 
   def showMessage(
     tpe: MessageType,
@@ -68,7 +69,7 @@ object LanguageClient {
 
       def configuration[A](
         v: ConfigurationValue[A]
-      ): F[A] = withClientF(
+      ): F[Option[A]] = withClientF(
         _.configuration(
           new ConfigurationParams(
             (new ConfigurationItem().tap(_.setSection(v.key)) :: Nil).asJava
@@ -85,7 +86,10 @@ object LanguageClient {
           case e: JsonElement => converters.gsonToCirce(e)
           case e              => throw new RuntimeException(s"Unexpected configuration value: $e")
         }
-        .flatMap(_.as[A](v.codec).liftTo[F])
+        .flatMap {
+          case Json.Null => none[A].pure[F]
+          case other     => other.as[A](v.codec).liftTo[F].map(_.some)
+        }
 
       def showMessage(
         tpe: MessageType,

modules/lsp/src/main/scala/playground/lsp/LanguageServer.scala

@@ -149,6 +149,7 @@ object LanguageServer {
 
       private val getFormatterWidth: F[Int] = LanguageClient[F]
         .configuration(ConfigurationValue.maxWidth)
+        .flatMap(_.liftTo[F](new Exception("couldn't find a formatter width")))
 
       val formattingProvider: Uri => F[List[language.TextEdit]] = FormattingProvider.provider(
         getFormatterWidth

modules/lsp/src/main/scala/playground/lsp/ServerBuilder.scala

@@ -9,10 +9,12 @@ import cats.syntax.all.*
 import fs2.compression.Compression
 import fs2.io.file.Files
 import fs2.io.net.Network
+import org.http4s.Uri
 import org.http4s.client.Client
 import org.http4s.client.middleware.Logger
 import org.http4s.ember.client.EmberClientBuilder
 import org.http4s.headers.Authorization
+import org.http4s.implicits.*
 import playground.FileRunner
 import playground.OperationRunner
 import playground.ServiceIndex
@@ -43,19 +45,23 @@ object ServerBuilder {
 
     implicit val stdlibRuntime: StdlibRuntime[F] = StdlibRuntime.instance[F]
 
+    val logger = Logger[F](
+      logHeaders = true,
+      logBody = true,
+      logAction = Some(msg =>
+        LanguageClient[F].logOutput(msg.linesWithSeparators.map("// " + _).mkString)
+      ),
+    )
+
     val makeClient = EmberClientBuilder
       .default[F]
       .build
-      .map(middleware.BaseUri[F])
-      .map(middleware.AuthorizationHeader[F])
       .map(
-        Logger[F](
-          logHeaders = true,
-          logBody = true,
-          logAction = Some(msg =>
-            LanguageClient[F].logOutput(msg.linesWithSeparators.map("// " + _).mkString)
-          ),
-        )
+        // logger gets applied first, so that it sees the final result
+        identity[Client[F]]
+          .compose(middleware.BaseUri[F])
+          .compose(middleware.AuthorizationHeader[F])
+          .compose(logger)
       )
 
     for {
@@ -101,21 +107,26 @@ object ServerBuilder {
 
     def BaseUri[F[_]: LanguageClient: MonadCancelThrow]: Client[F] => Client[F] =
       client =>
-        Client[F] { req =>
-          LanguageClient[F].configuration(ConfigurationValue.baseUri).toResource.flatMap { uri =>
-            client.run(
-              req.withUri(
-                req
-                  .uri
-                  .copy(
-                    scheme = uri.scheme,
-                    authority = uri.authority,
-                    // prefixing with uri.path
-                    path = uri.path.addSegments(req.uri.path.segments),
-                  )
-              )
-            )
-          }
+        Client[F] {
+          case req if req.uri != uri"/" => client.run(req)
+          case req =>
+            LanguageClient[F].configuration(ConfigurationValue.baseUri).toResource.flatMap {
+              case None => client.run(req)
+              case Some(uri) =>
+                client.run(
+                  req
+                    .withUri(
+                      req
+                        .uri
+                        .copy(
+                          scheme = uri.scheme,
+                          authority = uri.authority,
+                          // prefixing with uri.path
+                          path = uri.path.addSegments(req.uri.path.segments),
+                        )
+                    )
+                )
+            }
         }
 
     def AuthorizationHeader[F[_]: LanguageClient: MonadCancelThrow]: Client[F] => Client[F] =
@@ -125,8 +136,8 @@ object ServerBuilder {
             LanguageClient[F]
               .configuration(ConfigurationValue.authorizationHeader)
               .flatMap {
-                case v if v.trim.isEmpty() => request.pure[F]
-                case v => Authorization.parse(v).liftTo[F].map(request.putHeaders(_))
+                case None    => request.pure[F]
+                case Some(v) => Authorization.parse(v).liftTo[F].map(request.putHeaders(_))
               }
               .toResource
 

modules/lsp/src/test/scala/playground/lsp/harness/TestClient.scala

@@ -1,6 +1,7 @@
 package playground.lsp.harness
 
 import cats.data.Chain
+import cats.data.OptionT
 import cats.effect.IO
 import cats.effect.IOLocal
 import cats.syntax.all.*
@@ -77,10 +78,14 @@ object TestClient {
 
       def configuration[A](
         v: ConfigurationValue[A]
-      ): IO[A] = state
-        .get
-        .flatMap(_.configuration.get(v.key).liftTo[IO](new Throwable(s"key not found: ${v.key}")))
-        .flatMap(_.as[A](v.codec).liftTo[IO])
+      ): IO[Option[A]] =
+        OptionT {
+          state
+            .get
+            .map(_.configuration.get(v.key))
+        }
+          .semiflatMap(_.as[A](v.codec).liftTo[IO])
+          .value
 
       def showMessage(
         tpe: MessageType,

vscode-extension/package.json

@@ -67,12 +67,12 @@
           "type": "string",
           "format": "uri",
           "description": "The base URL of the HTTP server to use for running queries.",
-          "default": "http://localhost:8080"
+          "default": null
         },
         "smithyql.http.authorizationHeader": {
           "type": "string",
           "description": "The value of the Authorization header to use for running queries. Empty/whitespace strings will result in no header.",
-          "default": ""
+          "default": null
         },
         "smithyql.server.artifact": {
           "type": "string",