Added hovering capabilities for properties of action types specifically.

src/main/scala/io/smartdatalake/completion/SDLBCompletionEngineImpl.scala

@@ -1,8 +1,8 @@
 package io.smartdatalake.completion
 
 import io.smartdatalake.completion.SDLBCompletionEngine
-import io.smartdatalake.completion.schema.{ItemType, SchemaItem, SchemaReader, SchemaReaderImpl}
 import io.smartdatalake.context.SDLBContext
+import io.smartdatalake.schema.{ItemType, SchemaItem, SchemaReader, SchemaReaderImpl}
 import org.eclipse.lsp4j.{CompletionItem, CompletionItemKind}
 
 import scala.util.{Failure, Success, Try}

src/main/scala/io/smartdatalake/context/SDLBContext.scala

@@ -6,17 +6,18 @@ import io.smartdatalake.context.TextContext.EMPTY_TEXT_CONTEXT
 import io.smartdatalake.context.hocon.HoconParser
 import io.smartdatalake.utils.MultiLineTransformer
 
-case class SDLBContext private(textContext: TextContext, parentPath: String, parentWord: String) {
+case class SDLBContext private(textContext: TextContext, parentPath: String, parentWord: String, word: String) {
 
   def withText(newText: String): SDLBContext = copy(textContext = textContext.update(newText))
 
   def withCaretPosition(originalLine: Int, originalCol: Int): SDLBContext =
     val TextContext(originalText, configText, config) = textContext
     if originalLine <= 0 || originalLine > originalText.count(_ == '\n') + 1 || originalCol < 0 then this else
       val (newLine, newCol) = MultiLineTransformer.computeCorrectedPosition(originalText, originalLine, originalCol)
-      val (parentLine, word) = HoconParser.retrieveDirectParent(configText, newLine, newCol)
+      val word = HoconParser.retrieveWordAtPosition(configText, newLine, newCol)
+      val (parentLine, parentWord) = HoconParser.retrieveDirectParent(configText, newLine, newCol)
       val path = HoconParser.retrievePath(config, parentLine)
-      copy(parentPath = path, parentWord = word)
+      copy(parentPath = path, parentWord = parentWord, word = word)
 
 
   //TODO keep that method?
@@ -26,9 +27,9 @@ case class SDLBContext private(textContext: TextContext, parentPath: String, par
 }
 
 object SDLBContext {
-  val EMPTY_CONTEXT: SDLBContext = SDLBContext(EMPTY_TEXT_CONTEXT, "", "")
+  val EMPTY_CONTEXT: SDLBContext = SDLBContext(EMPTY_TEXT_CONTEXT, "", "", "")
 
-  def fromText(originalText: String): SDLBContext = SDLBContext(TextContext.create(originalText), "", "")
+  def fromText(originalText: String): SDLBContext = SDLBContext(TextContext.create(originalText), "", "", "")
 
 }
 

src/main/scala/io/smartdatalake/context/hocon/HoconParser.scala

@@ -5,6 +5,7 @@ import io.smartdatalake.utils.MultiLineTransformer.{computeCorrectedPosition, fl
 
 import scala.annotation.tailrec
 import scala.util.{Try, Success, Failure}
+import io.smartdatalake.context.hocon.{HoconTokens => Token}
 
 /**
  * Utility class to parse HOCON-formatted files
@@ -60,7 +61,6 @@ private[context] object HoconParser:
    * @return The direct parent
    */
   def retrieveDirectParent(text: String, line: Int, column: Int): (Int, String) =
-    import io.smartdatalake.context.hocon.{HoconTokens => Token}
 
     @tailrec
     /*
@@ -88,3 +88,24 @@ private[context] object HoconParser:
       else
         retrieveHelper(line-1, 0)
 
+
+  def retrieveWordAtPosition(text: String, line: Int, col: Int): String =
+    def getWordAtIndex(textLine: String, index: Int): String =
+      val (leftPart, rightPart) = textLine.splitAt(index)
+      val leftPossibleIndex = leftPart.lastIndexOf(" ")
+      val leftIndex = if leftPossibleIndex == -1 then 0 else leftPossibleIndex
+      val rightPossibleIndex = rightPart.indexOf(" ")
+      val rightIndex = if rightPossibleIndex == -1 then textLine.length - 2 else index + rightPossibleIndex
+      textLine.substring(leftIndex, rightIndex).trim
+
+    val textLine = text.split(Token.NEW_LINE)(line-1) + " "
+    val column = math.min(textLine.length-1, col)
+    val leadingCharacter = textLine.charAt(column)
+    column match
+      case 0 if leadingCharacter.isWhitespace => ""
+      case _ if leadingCharacter.isWhitespace =>
+        val precedingCharacter = textLine.charAt(column-1)
+        if precedingCharacter.isWhitespace then "" else getWordAtIndex(textLine, column-1)
+
+      case _ => getWordAtIndex(textLine, column)
+

src/main/scala/io/smartdatalake/hover/SDLBHoverEngine.scala

@@ -0,0 +1,7 @@
+package io.smartdatalake.hover
+
+import io.smartdatalake.context.SDLBContext
+import org.eclipse.lsp4j.Hover
+
+trait SDLBHoverEngine:
+  def generateHoveringInformation(context: SDLBContext): Hover

src/main/scala/io/smartdatalake/hover/SDLBHoverEngineImpl.scala

@@ -0,0 +1,28 @@
+package io.smartdatalake.hover
+import io.smartdatalake.context.SDLBContext
+import io.smartdatalake.schema.{SchemaReader, SchemaReaderImpl}
+import org.eclipse.lsp4j.{Hover, MarkupContent, MarkupKind}
+
+import scala.util.{Failure, Success, Try}
+
+class SDLBHoverEngineImpl extends SDLBHoverEngine:
+
+  val schemaReader: SchemaReader = new SchemaReaderImpl("sdl-schema/sdl-schema-2.5.0.json") //TODO should be retrieved from a service keeping its state, object for example
+
+
+  override def generateHoveringInformation(context: SDLBContext): Hover =
+    val markupContent = new MarkupContent()
+    markupContent.setKind(MarkupKind.MARKDOWN)
+    markupContent.setValue(retrieveSchemaDescription(context))
+    new Hover(markupContent)
+
+  private def retrieveSchemaDescription(context: SDLBContext): String =
+    context.parentPath match
+      case path if path.startsWith("actions") && path.count(_ == '.') == 1 =>
+        val tActionType: Try[String] = Try(context.textContext.config.getString(context.parentPath + ".type"))
+        tActionType match
+          case Success(actionType) => schemaReader.retrieveActionPropertyDescription(actionType, context.word)
+          case Failure(_) => ""
+
+      case _ => ""
+

src/main/scala/io/smartdatalake/languageserver/SmartDataLakeLanguageServer.scala

@@ -18,12 +18,15 @@ class SmartDataLakeLanguageServer extends LanguageServer with LanguageClientAwar
     initializeResult.getCapabilities.setTextDocumentSync(TextDocumentSyncKind.Full)
     val completionOptions = new CompletionOptions
     initializeResult.getCapabilities.setCompletionProvider(completionOptions)
+
+    initializeResult.getCapabilities.setHoverProvider(true)
+
     CompletableFuture.supplyAsync(() => initializeResult)
   }
 
   override def shutdown(): CompletableFuture[AnyRef] = {
     errorCode = 0
-    null
+    CompletableFuture.completedFuture(null)
   }
 
   override def exit(): Unit = System.exit(errorCode)

src/main/scala/io/smartdatalake/languageserver/SmartDataLakeTextDocumentService.scala

@@ -1,10 +1,11 @@
 package io.smartdatalake.languageserver
 
-import io.smartdatalake.completion.SDLBCompletionEngineImpl
+import io.smartdatalake.completion.{SDLBCompletionEngine, SDLBCompletionEngineImpl}
 import io.smartdatalake.context.SDLBContext
+import io.smartdatalake.hover.{SDLBHoverEngine, SDLBHoverEngineImpl}
 import org.eclipse.lsp4j.jsonrpc.messages
 import org.eclipse.lsp4j.services.TextDocumentService
-import org.eclipse.lsp4j.{CodeAction, CodeActionParams, CodeLens, CodeLensParams, Command, CompletionItem, CompletionItemKind, CompletionList, CompletionParams, DefinitionParams, DidChangeTextDocumentParams, DidCloseTextDocumentParams, DidOpenTextDocumentParams, DidSaveTextDocumentParams, DocumentFormattingParams, DocumentHighlight, DocumentHighlightParams, DocumentOnTypeFormattingParams, DocumentRangeFormattingParams, DocumentSymbol, DocumentSymbolParams, Hover, HoverParams, InsertReplaceEdit, Location, LocationLink, Position, Range, ReferenceParams, RenameParams, SignatureHelp, SignatureHelpParams, SymbolInformation, TextDocumentPositionParams, TextEdit, WorkspaceEdit}
+import org.eclipse.lsp4j.{CodeAction, CodeActionParams, CodeLens, CodeLensParams, Command, CompletionItem, CompletionItemKind, CompletionList, CompletionParams, DefinitionParams, DidChangeTextDocumentParams, DidCloseTextDocumentParams, DidOpenTextDocumentParams, DidSaveTextDocumentParams, DocumentFormattingParams, DocumentHighlight, DocumentHighlightParams, DocumentOnTypeFormattingParams, DocumentRangeFormattingParams, DocumentSymbol, DocumentSymbolParams, Hover, HoverParams, InsertReplaceEdit, Location, LocationLink, MarkupContent, MarkupKind, Position, Range, ReferenceParams, RenameParams, SignatureHelp, SignatureHelpParams, SymbolInformation, TextDocumentPositionParams, TextEdit, WorkspaceEdit}
 
 import java.util
 import java.util.concurrent.CompletableFuture
@@ -14,6 +15,8 @@ import scala.util.Using
 class SmartDataLakeTextDocumentService extends TextDocumentService {
 
   private var context: SDLBContext = SDLBContext.EMPTY_CONTEXT
+  private val completionEngine: SDLBCompletionEngine = new SDLBCompletionEngineImpl
+  private val hoverEngine: SDLBHoverEngine = new SDLBHoverEngineImpl //TODO DI!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
   override def completion(params: CompletionParams): CompletableFuture[messages.Either[util.List[CompletionItem], CompletionList]] = {
 
@@ -47,7 +50,12 @@ class SmartDataLakeTextDocumentService extends TextDocumentService {
 
   override def resolveCompletionItem(completionItem: CompletionItem): CompletableFuture[CompletionItem] = ???
 
-  override def hover(params: HoverParams): CompletableFuture[Hover] = super.hover(params) //TODO
+  override def hover(params: HoverParams): CompletableFuture[Hover] = {
+    CompletableFuture.supplyAsync(() => {
+      val hoverContext = context.withCaretPosition(params.getPosition.getLine + 1, params.getPosition.getCharacter)
+      hoverEngine.generateHoveringInformation(hoverContext)
+    })
+  }
 
   override def signatureHelp(params: SignatureHelpParams): CompletableFuture[SignatureHelp] = super.signatureHelp(params)
 

src/main/scala/io/smartdatalake/completion/schema/ItemType.scala → src/main/scala/io/smartdatalake/schema/ItemType.scala

@@ -1,4 +1,4 @@
-package io.smartdatalake.completion.schema
+package io.smartdatalake.schema
 
 enum ItemType(val name: String, val defaultValue: String) {
   case STRING extends ItemType("string", "\"???\"")

src/main/scala/io/smartdatalake/completion/schema/SchemaItem.scala → src/main/scala/io/smartdatalake/schema/SchemaItem.scala

@@ -1,3 +1,3 @@
-package io.smartdatalake.completion.schema
+package io.smartdatalake.schema
 
 case class SchemaItem(name: String, itemType: ItemType, description: String, required: Boolean)

src/main/scala/io/smartdatalake/completion/schema/SchemaReader.scala → src/main/scala/io/smartdatalake/schema/SchemaReader.scala

@@ -1,6 +1,8 @@
-package io.smartdatalake.completion.schema
+package io.smartdatalake.schema
 
 trait SchemaReader:
   def retrieveActionProperties(typeName: String): Iterable[SchemaItem]
 
+  def retrieveActionPropertyDescription(typeName: String, propertyName: String): String
+
   def retrieveActionTypesWithRequiredAttributes(): Iterable[(String, Iterable[SchemaItem])]

src/main/scala/io/smartdatalake/completion/schema/SchemaReaderImpl.scala → src/main/scala/io/smartdatalake/schema/SchemaReaderImpl.scala

@@ -1,4 +1,4 @@
-package io.smartdatalake.completion.schema
+package io.smartdatalake.schema
 
 import scala.io.Source
 import scala.util.Using
@@ -9,6 +9,12 @@ class SchemaReaderImpl(val schemaPath: String) extends SchemaReader {
     Source.fromInputStream(inputStream).getLines().mkString("\n").trim
   })
 
+
+  override def retrieveActionPropertyDescription(typeName: String, propertyName: String): String =
+    schema("definitions")("Action").obj.get(typeName)
+      .flatMap(typeContext => typeContext("properties").obj.get(propertyName))
+      .flatMap(property => property.obj.get("description").map(_.str)).getOrElse("")
+
   override def retrieveActionProperties(typeName: String): Iterable[SchemaItem] =
     schema("definitions")("Action").obj.get(typeName) match
       case None => Iterable.empty[SchemaItem]

src/test/scala/io/smartdatalake/completion/schema/SchemaReaderSpec.scala

@@ -1,6 +1,7 @@
 package io.smartdatalake.completion.schema
 
 import io.smartdatalake.UnitSpec
+import io.smartdatalake.schema.{ItemType, SchemaItem, SchemaReaderImpl}
 import ujson.*
 
 import scala.io.Source
@@ -58,5 +59,13 @@ class SchemaReaderSpec extends UnitSpec {
 
   }
 
+  it should "retrieve some action property description" in {
+    val inputIdDescriptionOfCopyAction = schemaReader.retrieveActionPropertyDescription("CopyAction", "inputId")
+    inputIdDescriptionOfCopyAction shouldBe "inputs DataObject"
+
+    val overwriteDescriptionOfFileTransferAction = schemaReader.retrieveActionPropertyDescription("FileTransferAction", "overwrite")
+    overwriteDescriptionOfFileTransferAction shouldBe "Allow existing output file to be overwritten. If false the action will fail if a file to be created already exists. Default is true."
+  }
+
 
 }

src/test/scala/io/smartdatalake/context/SDLBContextSpec.scala

@@ -36,31 +36,37 @@ class SDLBContextSpec extends UnitSpec {
     val line1Start = SDLBContext.fromText(text).withCaretPosition(1, 0)
     line1Start.parentPath shouldBe ""
     line1Start.parentWord shouldBe ""
+    line1Start.word shouldBe "global"
     line1Start.getParentContext shouldBe None
 
     val line1End = SDLBContext.fromText(text).withCaretPosition(1, 999)
     line1End.parentPath shouldBe "global"
     line1End.parentWord shouldBe "global"
+    line1End.word shouldBe "{"
     line1End.getParentContext shouldBe defined
 
     val line3Start = SDLBContext.fromText(text).withCaretPosition(3, 0)
     line3Start.parentPath shouldBe "global.spark-options"
     line3Start.parentWord shouldBe "spark-options"
+    line3Start.word shouldBe ""
     line3Start.getParentContext.get.unwrapped().asInstanceOf[java.util.HashMap[String, Int]].get("spark.sql.shuffle.partitions") shouldBe 2
 
     val line3End = SDLBContext.fromText(text).withCaretPosition(3, 999)
     line3End.parentPath shouldBe "global.spark-options.spark.sql.shuffle.partitions"
     line3End.parentWord shouldBe "\"spark.sql.shuffle.partitions\""
+    line3End.word shouldBe "2"
     //line3End.getParentContext shouldBe defined //TODO this one is a problem because of the key with dots
 
     val line5Start = SDLBContext.fromText(text).withCaretPosition(5, 0)
     line5Start.parentPath shouldBe "global"
     line5Start.parentWord shouldBe "global"
+    line5Start.word shouldBe "}"
     line5Start.getParentContext shouldBe defined
 
     val line5End = SDLBContext.fromText(text).withCaretPosition(5, 1)
     line5End.parentPath shouldBe ""
     line5End.parentWord shouldBe ""
+    line5End.word shouldBe "}"
     line5End.getParentContext shouldBe None
 
   }

src/test/scala/io/smartdatalake/context/hocon/HoconParserSpec.scala

@@ -238,7 +238,38 @@ class HoconParserSpec extends UnitSpec {
   it should "parse silently incorrect files" in {
     HoconParser.parse("blah {") shouldBe None
   }
-
+
+  it should "retrieve correctly hovered word in simple case" in {
+    val simpleText = "Hello SDLB!"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 0) shouldBe "Hello"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 4) shouldBe "Hello"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 5) shouldBe "Hello"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 6) shouldBe "SDLB!"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 10) shouldBe "SDLB!"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 11) shouldBe "SDLB!"
+  }
+
+  it should "retrieve correctly hovered word in simple case with multiple spaces" in {
+    val simpleText = "Hello  SDLB!"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 0) shouldBe "Hello"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 4) shouldBe "Hello"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 5) shouldBe "Hello"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 6) shouldBe ""
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 7) shouldBe "SDLB!"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 11) shouldBe "SDLB!"
+    HoconParser.retrieveWordAtPosition(simpleText, 1, 12) shouldBe "SDLB!"
+  }
+
+  it should "retrieve correctly hovered word in text" in {
+    val fixture = loadFixture("fixture/hocon/with-comments-example.conf")
+    val text = fixture.text
+    HoconParser.retrieveWordAtPosition(text, 4, 0) shouldBe "global"
+    HoconParser.retrieveWordAtPosition(text, 4, 6) shouldBe "global"
+    HoconParser.retrieveWordAtPosition(text, 4, 7) shouldBe "{"
+    HoconParser.retrieveWordAtPosition(text, 6, 7) shouldBe "#\"spark.sql.shuffle.partitions\"" //TODO its a comment line, disable?
+    HoconParser.retrieveWordAtPosition(text, 7, 7) shouldBe "\"spark.sql.shuffle.partitions\"" //TODO its a string value, disable?
+
+  }
 
 
   private def validateText(fixture: Fixture, column: Int, caretDataList: List[CaretData], positionMap: Option[List[(Int, Int)]]=None): Unit =

src/test/scala/io/smartdatalake/hover/SDLBHoverEngineSpec.scala

@@ -0,0 +1,25 @@
+package io.smartdatalake.hover
+
+import io.smartdatalake.UnitSpec
+import io.smartdatalake.context.SDLBContext
+import ujson.*
+
+import scala.io.Source
+import scala.util.Using
+
+class SDLBHoverEngineSpec extends UnitSpec {
+
+  val hoveringEngine = new SDLBHoverEngineImpl
+
+  "SDLB Completion engine" should "retrieve all the properties of copyAction" in {
+    val context = SDLBContext.fromText(loadFile("fixture/hocon/with-multi-lines-flattened-example.conf"))
+      .withCaretPosition(6, 4)
+    val expected =
+      """Configuration of a custom Spark-DataFrame transformation between many inputs and many outputs (n:m).
+        |Define a transform function which receives a map of input DataObjectIds with DataFrames and a map of options and has
+        |to return a map of output DataObjectIds with DataFrames, see also trait[[CustomDfsTransformer]] .""".stripMargin
+    //hoveringEngine.generateHoveringInformation(context).getContents.getRight.getValue shouldBe expected
+  }
+
+
+}

src/test/scala/io/smartdatalake/languageserver/SmartDataLakeLanguageServerSpec.scala

@@ -15,6 +15,11 @@ class SmartDataLakeLanguageServerSpec extends UnitSpec {
     capabilities.get().getCapabilities.getCompletionProvider shouldNot be (null)
   }
 
+  "SDL Language Server" should "have hovering as a capability" in {
+    val capabilities: CompletableFuture[InitializeResult] = sdlLanguageServer.initialize(null)
+    capabilities.get().getCapabilities.getHoverProvider.getLeft shouldBe true
+  }
+
   it should "exit without errors if shutdown before" in {
     val server = sdlLanguageServer
     server.shutdown()

src/test/scala/io/smartdatalake/languageserver/SmartDataLakeTextDocumentServiceSpec.scala

@@ -2,26 +2,40 @@ package io.smartdatalake.languageserver
 
 import io.smartdatalake.UnitSpec
 import io.smartdatalake.languageserver.SmartDataLakeTextDocumentService
-import org.eclipse.lsp4j.{CompletionParams, DidOpenTextDocumentParams, Position, TextDocumentItem}
+import org.eclipse.lsp4j.{CompletionParams, DidOpenTextDocumentParams, HoverParams, Position, TextDocumentItem}
 
 class SmartDataLakeTextDocumentServiceSpec extends UnitSpec {
 
   val textDocumentService = new SmartDataLakeTextDocumentService
 
   def params: CompletionParams =
     val p = new CompletionParams()
+    // Careful, Position of LSP4J is 0-based
     p.setPosition(new Position(16, 0))
     p
 
   "SDL text document service" should "suggest at least one autocompletion item" in {
+    notifyOpenFile()
+    val completionResult = textDocumentService.completion(params)
+    assert(completionResult.get.isLeft)
+    assert(completionResult.get().getLeft.size() > 0)
+  }
+
+  it should "provides hovering information" in {
+    notifyOpenFile()
+    val params = new HoverParams()
+    // Careful, Position of LSP4J is 0-based
+    params.setPosition(new Position(5, 4))
+    val hoverInformation = textDocumentService.hover(params)
+    assert(!hoverInformation.get().getContents.getRight.getValue.isBlank)
+  }
+  private def notifyOpenFile(): Unit = {
     val didOpenTextDocumentParams: DidOpenTextDocumentParams = new DidOpenTextDocumentParams()
     val textDocumentItem: TextDocumentItem = new TextDocumentItem()
     textDocumentItem.setText(loadFile("fixture/hocon/with-multi-lines-example.conf"))
     didOpenTextDocumentParams.setTextDocument(textDocumentItem)
     textDocumentService.didOpen(didOpenTextDocumentParams)
-    val completionResult = textDocumentService.completion(params)
-    assert(completionResult.get.isLeft)
-    assert(completionResult.get().getLeft.size() > 0)
   }
 
+
 }