Add evaluation for one-shot expressions (#1749)

docs/language-server/protocol-language-server.md

@@ -115,6 +115,7 @@ transport formats, please look [here](./protocol-architecture).
   - [`executionContext/expressionUpdates`](#executioncontextexpressionupdates)
   - [`executionContext/executionFailed`](#executioncontextexecutionfailed)
   - [`executionContext/executionStatus`](#executioncontextexecutionstatus)
+  - [`executionContext/executeExpression`](#executioncontextexecuteexpression)
   - [`executionContext/attachVisualisation`](#executioncontextattachvisualisation)
   - [`executionContext/detachVisualisation`](#executioncontextdetachvisualisation)
   - [`executionContext/modifyVisualisation`](#executioncontextmodifyvisualisation)
@@ -1280,6 +1281,7 @@ destroying the context.
 - [`executionContext/recompute`](#executioncontextrecompute)
 - [`executionContext/push`](#executioncontextpush)
 - [`executionContext/pop`](#executioncontextpop)
+- [`executionContext/executeExpression`](#executioncontextexecuteexpression)
 - [`executionContext/attachVisualisation`](#executioncontextattachvisualisation)
 - [`executionContext/modifyVisualisation`](#executioncontextmodifyvisualisation)
 - [`executionContext/detachVisualisation`](#executioncontextdetachvisualisation)
@@ -2751,6 +2753,47 @@ Sent from the server to the client to inform about a status of execution.
 
 None
 
+### `executionContext/executeExpression`
+
+This message allows the client to execute an arbitrary expression on a given
+node. It behaves like oneshot
+[`executionContext/attachVisualisation`](#executioncontextattachvisualisation)
+visualisation request, meaning that the visualisation expression will be
+executed only once.
+
+- **Type:** Request
+- **Direction:** Client -> Server
+- **Connection:** Protocol
+- **Visibility:** Public
+
+#### Parameters
+
+```typescript
+interface ExecuteExpressionRequest {
+  visualisationId: UUID;
+  expressionId: UUID;
+  visualisationConfig: VisualisationConfiguration;
+}
+```
+
+#### Result
+
+```typescript
+null;
+```
+
+#### Errors
+
+- [`AccessDeniedError`](#accessdeniederror) when the user does not hold the
+  `executionContext/canModify` capability for this context.
+- [`ContextNotFoundError`](#contextnotfounderror) when context can not be found
+  by provided id.
+- [`ModuleNotFoundError`](#modulenotfounderror) to signal that the module with
+  the visualisation cannot be found.
+- [`VisualisationExpressionError`](#visualisationexpressionerror) to signal that
+  the expression specified in the `VisualisationConfiguration` cannot be
+  evaluated.
+
 ### `executionContext/attachVisualisation`
 
 This message allows the client to attach a visualisation, potentially

engine/language-server/src/main/scala/org/enso/languageserver/protocol/json/JsonConnectionController.scala

@@ -38,13 +38,15 @@ import org.enso.languageserver.requesthandler.text._
 import org.enso.languageserver.requesthandler.visualisation.{
   AttachVisualisationHandler,
   DetachVisualisationHandler,
+  ExecuteExpressionHandler,
   ModifyVisualisationHandler
 }
 import org.enso.languageserver.runtime.ContextRegistryProtocol
 import org.enso.languageserver.runtime.ExecutionApi._
 import org.enso.languageserver.runtime.VisualisationApi.{
   AttachVisualisation,
   DetachVisualisation,
+  ExecuteExpression,
   ModifyVisualisation
 }
 import org.enso.languageserver.search.SearchApi._
@@ -94,7 +96,7 @@ class JsonConnectionController(
 
   import context.dispatcher
 
-  implicit val timeout = Timeout(requestTimeout)
+  implicit val timeout: Timeout = Timeout(requestTimeout)
 
   override def receive: Receive = {
     case JsonRpcServer.WebConnect(webActor) =>
@@ -333,6 +335,8 @@ class JsonConnectionController(
       Completion -> search.CompletionHandler
         .props(requestTimeout, suggestionsHandler),
       Import -> search.ImportHandler.props(requestTimeout, suggestionsHandler),
+      ExecuteExpression -> ExecuteExpressionHandler
+        .props(rpcSession.clientId, requestTimeout, contextRegistry),
       AttachVisualisation -> AttachVisualisationHandler
         .props(rpcSession.clientId, requestTimeout, contextRegistry),
       DetachVisualisation -> DetachVisualisationHandler

engine/language-server/src/main/scala/org/enso/languageserver/protocol/json/JsonRpc.scala

@@ -52,6 +52,7 @@ object JsonRpc {
     .registerRequest(ExecutionContextPush)
     .registerRequest(ExecutionContextPop)
     .registerRequest(ExecutionContextRecompute)
+    .registerRequest(ExecuteExpression)
     .registerRequest(AttachVisualisation)
     .registerRequest(DetachVisualisation)
     .registerRequest(ModifyVisualisation)

engine/language-server/src/main/scala/org/enso/languageserver/requesthandler/visualisation/ExecuteExpressionHandler.scala

@@ -0,0 +1,90 @@
+package org.enso.languageserver.requesthandler.visualisation
+
+import akka.actor.{Actor, ActorLogging, ActorRef, Cancellable, Props}
+import org.enso.jsonrpc._
+import org.enso.languageserver.data.ClientId
+import org.enso.languageserver.requesthandler.RequestTimeout
+import org.enso.languageserver.runtime.VisualisationApi.ExecuteExpression
+import org.enso.languageserver.runtime.{
+  ContextRegistryProtocol,
+  RuntimeFailureMapper
+}
+import org.enso.languageserver.util.UnhandledLogging
+
+import scala.concurrent.duration.FiniteDuration
+
+/** A request handler for `executionContext/executeExpression` command.
+  *
+  * @param clientId an unique identifier of the client
+  * @param timeout request timeout
+  * @param contextRegistry a reference to the context registry.
+  */
+class ExecuteExpressionHandler(
+  clientId: ClientId,
+  timeout: FiniteDuration,
+  contextRegistry: ActorRef
+) extends Actor
+    with ActorLogging
+    with UnhandledLogging {
+
+  import context.dispatcher
+
+  override def receive: Receive = requestStage
+
+  private def requestStage: Receive = {
+    case Request(
+          ExecuteExpression,
+          id,
+          params: ExecuteExpression.Params
+        ) =>
+      contextRegistry ! ContextRegistryProtocol.ExecuteExpression(
+        clientId,
+        params.visualisationId,
+        params.expressionId,
+        params.visualisationConfig
+      )
+      val cancellable =
+        context.system.scheduler.scheduleOnce(timeout, self, RequestTimeout)
+      context.become(responseStage(id, sender(), cancellable))
+  }
+
+  private def responseStage(
+    id: Id,
+    replyTo: ActorRef,
+    cancellable: Cancellable
+  ): Receive = {
+    case RequestTimeout =>
+      log.error("Request [{}] timed out.", id)
+      replyTo ! ResponseError(Some(id), Errors.RequestTimeout)
+      context.stop(self)
+
+    case ContextRegistryProtocol.VisualisationAttached =>
+      replyTo ! ResponseResult(ExecuteExpression, id, Unused)
+      cancellable.cancel()
+      context.stop(self)
+
+    case error: ContextRegistryProtocol.Failure =>
+      replyTo ! ResponseError(Some(id), RuntimeFailureMapper.mapFailure(error))
+      cancellable.cancel()
+      context.stop(self)
+  }
+
+}
+
+object ExecuteExpressionHandler {
+
+  /** Creates configuration object used to create an
+    * [[ExecuteExpressionHandler]].
+    *
+    * @param clientId an unique identifier of the client
+    * @param timeout request timeout
+    * @param runtime a reference to the context registry
+    */
+  def props(
+    clientId: ClientId,
+    timeout: FiniteDuration,
+    runtime: ActorRef
+  ): Props =
+    Props(new ExecuteExpressionHandler(clientId, timeout, runtime))
+
+}

engine/language-server/src/main/scala/org/enso/languageserver/runtime/ContextEventsListener.scala

@@ -4,6 +4,8 @@ import akka.actor.{Actor, ActorLogging, ActorRef, Props}
 import akka.pattern.pipe
 import org.enso.languageserver.data.Config
 import org.enso.languageserver.runtime.ContextRegistryProtocol.{
+  DetachVisualisation,
+  RegisterOneshotVisualisation,
   VisualisationContext,
   VisualisationUpdate
 }
@@ -60,9 +62,31 @@ final class ContextEventsListener(
     }
   }
 
-  override def receive: Receive = withState(Vector())
+  override def receive: Receive = withState(Set(), Vector())
+
+  def withState(
+    oneshotVisualisations: Set[Api.VisualisationContext],
+    expressionUpdates: Vector[Api.ExpressionUpdate]
+  ): Receive = {
+
+    case RegisterOneshotVisualisation(
+          contextId,
+          visualisationId,
+          expressionId
+        ) =>
+      val visualisationContext =
+        Api.VisualisationContext(
+          visualisationId,
+          contextId,
+          expressionId
+        )
+      context.become(
+        withState(
+          oneshotVisualisations + visualisationContext,
+          expressionUpdates
+        )
+      )
 
-  def withState(expressionUpdates: Vector[Api.ExpressionUpdate]): Receive = {
     case Api.VisualisationUpdate(ctx, data) if ctx.contextId == contextId =>
       val payload =
         VisualisationUpdate(
@@ -74,10 +98,24 @@ final class ContextEventsListener(
           data
         )
       sessionRouter ! DeliverToBinaryController(rpcSession.clientId, payload)
+      if (oneshotVisualisations.contains(ctx)) {
+        context.parent ! DetachVisualisation(
+          rpcSession.clientId,
+          contextId,
+          ctx.visualisationId,
+          ctx.expressionId
+        )
+        context.become(
+          withState(
+            oneshotVisualisations - ctx,
+            expressionUpdates
+          )
+        )
+      }
 
     case Api.ExpressionUpdates(`contextId`, apiUpdates) =>
       context.become(
-        withState(expressionUpdates :++ apiUpdates)
+        withState(oneshotVisualisations, expressionUpdates :++ apiUpdates)
       )
 
     case Api.ExecutionFailed(`contextId`, error) =>
@@ -115,7 +153,7 @@ final class ContextEventsListener(
 
     case RunExpressionUpdates if expressionUpdates.nonEmpty =>
       runExpressionUpdates(expressionUpdates)
-      context.become(withState(Vector()))
+      context.become(withState(oneshotVisualisations, Vector()))
 
     case RunExpressionUpdates if expressionUpdates.isEmpty =>
   }

engine/language-server/src/main/scala/org/enso/languageserver/runtime/ContextRegistry.scala

@@ -182,20 +182,42 @@ final class ContextRegistry(
           sender() ! AccessDenied
         }
 
+      case ExecuteExpression(clientId, visualisationId, expressionId, cfg) =>
+        val contextId = cfg.executionContextId
+        if (store.hasContext(clientId, contextId)) {
+          store.getListener(contextId).foreach { listener =>
+            listener ! RegisterOneshotVisualisation(
+              contextId,
+              visualisationId,
+              expressionId
+            )
+          }
+          val handler =
+            context.actorOf(
+              AttachVisualisationHandler.props(config, timeout, runtime)
+            )
+          handler.forward(
+            Api.AttachVisualisation(
+              visualisationId,
+              expressionId,
+              convertVisualisationConfig(cfg)
+            )
+          )
+        } else {
+          sender() ! AccessDenied
+        }
+
       case AttachVisualisation(clientId, visualisationId, expressionId, cfg) =>
         if (store.hasContext(clientId, cfg.executionContextId)) {
           val handler =
             context.actorOf(
               AttachVisualisationHandler.props(config, timeout, runtime)
             )
-
-          val configuration = convertVisualisationConfig(cfg)
-
           handler.forward(
             Api.AttachVisualisation(
               visualisationId,
               expressionId,
-              configuration
+              convertVisualisationConfig(cfg)
             )
           )
         } else {
@@ -213,7 +235,6 @@ final class ContextRegistry(
             context.actorOf(
               DetachVisualisationHandler.props(config, timeout, runtime)
             )
-
           handler.forward(
             Api.DetachVisualisation(contextId, visualisationId, expressionId)
           )

engine/language-server/src/main/scala/org/enso/languageserver/runtime/ContextRegistryProtocol.scala

@@ -307,14 +307,53 @@ object ContextRegistryProtocol {
     diagnostics: Seq[ExecutionDiagnostic]
   )
 
+  /** Requests the language server to execute an expression provided in the
+    * `visualisationConfig` on an expression specified by `expressionId`.
+    *
+    * @param clientId the requester id
+    * @param visualisationId an identifier of a visualisation
+    * @param expressionId an identifier of an expression which is visualised
+    * @param visualisationConfig a configuration object for properties of the
+    * visualisation
+    */
+  case class ExecuteExpression(
+    clientId: ClientId,
+    visualisationId: UUID,
+    expressionId: UUID,
+    visualisationConfig: VisualisationConfiguration
+  ) extends ToLogString {
+
+    /** @inheritdoc */
+    override def toLogString(shouldMask: Boolean): String =
+      "ExecuteExpression(" +
+      s"clientId=$clientId," +
+      s"visualisationId=$visualisationId," +
+      s"expressionId=$expressionId,visualisationConfig=" +
+      visualisationConfig.toLogString(shouldMask) +
+      ")"
+  }
+
+  /** Registers a oneshot visualisation that will be detached after the first
+    * execution.
+    *
+    * @param contextId execution context identifier
+    * @param visualisationId an identifier of a visualisation
+    * @param expressionId an identifier of an expression which is visualised
+    */
+  case class RegisterOneshotVisualisation(
+    contextId: ContextId,
+    visualisationId: UUID,
+    expressionId: UUID
+  )
+
   /** Requests the language server to attach a visualisation to the expression
     * specified by `expressionId`.
     *
     * @param clientId the requester id
     * @param visualisationId an identifier of a visualisation
     * @param expressionId an identifier of an expression which is visualised
     * @param visualisationConfig a configuration object for properties of the
-    *                            visualisation
+    * visualisation
     */
   case class AttachVisualisation(
     clientId: ClientId,
@@ -333,8 +372,7 @@ object ContextRegistryProtocol {
       ")"
   }
 
-  /** Signals that attaching a visualisation has succeeded.
-    */
+  /** Signals that attaching a visualisation has succeeded. */
   case object VisualisationAttached
 
   /** Requests the language server to detach a visualisation from the expression