IJPL-160418 Introduce a unique ID for a Project

To use Project in communication between backend and frontend, we need some sort of serializable unique id that we'd be able to pass through RPC or Rhizome.

In split mode we have to pass this id through RD protocol, because this is how Projects are synchronized there at the moment.

GitOrigin-RevId: c92b1c40830d9f7acf9fd4d0b0e13fa1828e8786

platform/platform-impl/intellij.platform.ide.impl.iml

@@ -142,6 +142,7 @@
     <orderEntry type="module" module-name="intellij.platform.kernel" />
     <orderEntry type="module" module-name="intellij.platform.ide.progress" />
     <orderEntry type="library" name="googlecode.plist.dd" level="project" />
+    <orderEntry type="module" module-name="intellij.platform.project" />
     <orderEntry type="module" module-name="intellij.platform.jbr" />
     <orderEntry type="module" module-name="intellij.platform.ui.jcef" />
     <orderEntry type="module" module-name="fleet.util.core" />

platform/platform-impl/src/com/intellij/openapi/project/impl/ProjectManagerImpl.kt

@@ -72,6 +72,8 @@ import com.intellij.platform.PlatformProjectOpenProcessor.Companion.isLoadedFrom
 import com.intellij.platform.attachToProjectAsync
 import com.intellij.platform.diagnostic.telemetry.impl.span
 import com.intellij.platform.ide.progress.ModalTaskOwner
+import com.intellij.platform.project.PROJECT_ID
+import com.intellij.platform.project.ProjectId
 import com.intellij.platform.workspace.jps.JpsMetrics
 import com.intellij.projectImport.ProjectAttachProcessor
 import com.intellij.serviceContainer.ComponentManagerImpl
@@ -1285,6 +1287,8 @@ private suspend fun initProject(
     }
 
     project.putUserDataIfAbsent(PROJECT_PATH, file)
+    project.putUserDataIfAbsent(PROJECT_ID, ProjectId.create())
+
     project.registerComponents()
     registerComponentActivity?.end()
 

platform/project/shared/intellij.platform.project.iml

@@ -1,5 +1,26 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <module type="JAVA_MODULE" version="4">
+<component name="FacetManager">
+    <facet type="kotlin-language" name="Kotlin">
+      <configuration version="5" platform="JVM 17" allPlatforms="JVM [17]" useProjectSettings="false">
+        <compilerSettings>
+          <option name="additionalArguments" value="-Xjvm-default=all" />
+        </compilerSettings>
+        <compilerArguments>
+          <stringArguments>
+            <stringArg name="jvmTarget" arg="17" />
+            <stringArg name="apiVersion" arg="1.9" />
+            <stringArg name="languageVersion" arg="1.9" />
+          </stringArguments>
+          <arrayArguments>
+            <arrayArg name="pluginClasspaths">
+              <args>$KOTLIN_BUNDLED$/lib/kotlinx-serialization-compiler-plugin.jar</args>
+            </arrayArg>
+          </arrayArguments>
+        </compilerArguments>
+      </configuration>
+    </facet>
+  </component>
   <component name="NewModuleRootManager" inherit-compiler-output="true">
     <exclude-output />
     <content url="file://$MODULE_DIR$">
@@ -8,5 +29,10 @@
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="kotlin-stdlib" level="project" />
+    <orderEntry type="library" name="kotlinx-serialization-core" level="project" />
+    <orderEntry type="library" name="kotlinx-serialization-json" level="project" />
+    <orderEntry type="module" module-name="intellij.platform.kernel" />
+    <orderEntry type="module" module-name="intellij.platform.projectModel" />
   </component>
 </module>

platform/project/shared/src/ProjectId.kt

@@ -0,0 +1,98 @@
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.platform.project
+
+import com.intellij.openapi.project.Project
+import com.intellij.openapi.project.ProjectManager
+import com.intellij.openapi.util.Key
+import fleet.util.UID
+import kotlinx.serialization.Serializable
+import org.jetbrains.annotations.ApiStatus
+
+@JvmField
+@ApiStatus.Internal
+val PROJECT_ID = Key.create<ProjectId>("ProjectImpl.PROJECT_ID")
+
+/**
+ * Represents a unique identifier for a [Project].
+ * This [ProjectId] is shared by frontend and backend.
+ *
+ * To retrieve the id of a given project use [projectIdOrNull] or [projectId]
+ */
+@Serializable
+@ApiStatus.Internal
+class ProjectId(private val id: UID) {
+
+  /**
+   * This API is necessary only for Split Mode, functionality that uses RD Protocol
+   * for RPC use just [ProjectId], since it is serializable
+   */
+  @ApiStatus.Internal
+  fun serializeToString(): String {
+    return id.toString()
+  }
+
+  companion object {
+    /**
+     * Creates a new unique identifier for a [Project]
+     */
+    @ApiStatus.Internal
+    fun create(): ProjectId {
+      return ProjectId(UID.random())
+    }
+
+    /**
+     * This API is necessary only for Split Mode, functionality that uses RD Protocol
+     * for RPC use just [ProjectId], since it is serializable
+     */
+    @ApiStatus.Internal
+    fun deserializeFromString(value: String): ProjectId {
+      return ProjectId(UID.fromString(value))
+    }
+  }
+}
+
+/**
+ * Provides the [ProjectId] for the given [Project].
+ * This [ProjectId] can be used for RPC calls between frontend and backend
+ *
+ * @return The [ProjectId] instance associated with the provided [Project],
+ * or null if [Project]'s implementation didn't assign id to it.
+ */
+@ApiStatus.Internal
+fun Project.projectIdOrNull(): ProjectId? {
+  return getUserData(PROJECT_ID)
+}
+
+/**
+ * Provides the [ProjectId] for the given [Project].
+ * This [ProjectId] can be used for RPC calls between frontend and backend
+ *
+ * @return The [ProjectId] instance associated with the provided [Project],
+ * @throws IllegalStateException if [Project]'s implementation didn't assign id to it.
+ */
+@ApiStatus.Internal
+fun Project.projectId(): ProjectId {
+  return projectIdOrNull() ?: error("Project ID is not set for $this")
+}
+
+/**
+ * Provides [Project] for the given [ProjectId].
+ *
+ * @return The [Project] instance associated with the provided [ProjectId],
+ * or null if there is no project with the given [ProjectId].
+ */
+@ApiStatus.Internal
+fun ProjectId.findProjectOrNull(): Project? {
+  return ProjectManager.getInstance().openProjects.firstOrNull { it.getUserData(PROJECT_ID) == this }
+}
+
+/**
+ * Provides [Project] for the given [ProjectId].
+ *
+ * @return The [Project] instance associated with the provided [ProjectId],
+ * @throws IllegalStateException if there is no project with the given [ProjectId].
+ */
+@ApiStatus.Internal
+fun ProjectId.findProject(): Project {
+  return findProjectOrNull() ?: error("Project is not found for $this")
+}