fix(amazonq): use user provided node runtime

plugins/amazonq/codewhisperer/jetbrains-community/src/software/aws/toolkits/jetbrains/services/codewhisperer/settings/CodeWhispererConfigurable.kt

@@ -83,6 +83,21 @@ class CodeWhispererConfigurable(private val project: Project) :
                     .resizableColumn()
                     .align(Align.FILL)
             }
+            row(message("amazonqFeatureDev.placeholder.node_runtime_path")) {
+                val fileChooserDescriptor = FileChooserDescriptorFactory.createSingleFileDescriptor()
+                fileChooserDescriptor.isForcedToUseIdeaFileChooser = true
+
+                textFieldWithBrowseButton(fileChooserDescriptor = fileChooserDescriptor)
+                    .bindText(
+                        { LspSettings.getInstance().getNodeRuntimePath().orEmpty() },
+                        { LspSettings.getInstance().setNodeRuntimePath(it) }
+                    )
+                    .applyToComponent {
+                        emptyText.text = message("executableCommon.auto_managed")
+                    }
+                    .resizableColumn()
+                    .align(Align.FILL)
+            }
         }
 
         group(message("aws.settings.codewhisperer.group.general")) {

plugins/amazonq/shared/jetbrains-community/src/software/aws/toolkits/jetbrains/services/amazonq/lsp/AmazonQLspService.kt

@@ -5,16 +5,19 @@
 
 import com.google.gson.ToNumberPolicy
 import com.intellij.execution.configurations.GeneralCommandLine
+import com.intellij.execution.configurations.PathEnvironmentVariableUtil
 import com.intellij.execution.impl.ExecutionManagerImpl
 import com.intellij.execution.process.KillableColoredProcessHandler
 import com.intellij.execution.process.KillableProcessHandler
 import com.intellij.execution.process.ProcessEvent
 import com.intellij.execution.process.ProcessListener
 import com.intellij.execution.process.ProcessOutputType
+import com.intellij.notification.NotificationAction
 import com.intellij.openapi.Disposable
 import com.intellij.openapi.components.Service
 import com.intellij.openapi.components.service
 import com.intellij.openapi.components.serviceIfCreated
+import com.intellij.openapi.options.ShowSettingsUtil
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.util.Disposer
 import com.intellij.openapi.util.Key
@@ -76,6 +79,8 @@
 import software.aws.toolkits.jetbrains.services.amazonq.profile.QDefaultServiceConfig
 import software.aws.toolkits.jetbrains.services.telemetry.ClientMetadata
 import software.aws.toolkits.jetbrains.settings.LspSettings
+import software.aws.toolkits.jetbrains.utils.notifyInfo
+import software.aws.toolkits.resources.message
 import java.io.IOException
 import java.io.OutputStreamWriter
 import java.io.PipedInputStream
@@ -86,7 +91,9 @@
 import java.net.URI
 import java.nio.charset.StandardCharsets
 import java.nio.file.Files
+import java.nio.file.Path
 import java.util.concurrent.Future
+import java.util.concurrent.TimeUnit
 import kotlin.time.Duration.Companion.seconds
 
 // https://github.com/redhat-developer/lsp4ij/blob/main/src/main/java/com/redhat/devtools/lsp4ij/server/LSPProcessListener.java
@@ -372,7 +379,9 @@
         }
 
         val node = if (SystemInfo.isWindows) "node.exe" else "node"
-        val cmd = NodeExePatcher.patch(artifact.resolve(node))
+        var nodePath = getNodeRuntimePath(artifact.resolve(node))
+
+        val cmd = NodeExePatcher.patch(nodePath)
             .withParameters(
                 LspSettings.getInstance().getArtifactPath() ?: artifact.resolve("aws-lsp-codewhisperer.js").toString(),
                 "--stdio",
@@ -492,6 +501,103 @@
         }
     }
 
+    /**
+     * Resolves the path to a valid Node.js runtime in the following order of preference:
+     * 1. Uses the provided nodePath if it exists and is executable
+     * 2. Uses user-specified runtime path from LSP settings if available
+     * 3. Uses system Node.js if version 18+ is available
+     * 4. Falls back to original nodePath with a notification to configure runtime
+     *
+     * @param nodePath The initial Node.js runtime path to check, typically from the artifact directory
+     * @return Path The resolved Node.js runtime path to use for the LSP server
+     *
+     * Side effects:
+     * - Logs warnings if initial runtime path is invalid
+     * - Logs info when using alternative runtime path
+     * - Shows notification to user if no valid Node.js runtime is found
+     *
+     * Note: The function will return a path even if no valid runtime is found, but the LSP server
+     * may fail to start in that case. The caller should handle potential runtime initialization failures.
+     */
+    private fun getNodeRuntimePath(nodePath: Path): Path {
+        if (Files.exists(nodePath) && Files.isExecutable(nodePath)) {
+            return nodePath
+        }
+        // use alternative node runtime if it is not found
+        LOG.warn { "Node Runtime download failed. Fallback to user specified node runtime " }
+        // attempt to use user provided node runtime path
+        val nodeRuntime = LspSettings.getInstance().getNodeRuntimePath()
+        if (!nodeRuntime.isNullOrEmpty()) {
+            LOG.info { "Using node from $nodeRuntime " }
+            return Path.of(nodeRuntime)
+        } else {
+            val localNode = locateNodeCommand()
+            if (localNode != null) {
+                LOG.info { "Using node from ${localNode.toAbsolutePath()}" }
+                return localNode
+            }
+            notifyInfo(
+                "Amazon Q",
+                message("amazonqFeatureDev.placeholder.node_runtime_message"),
+                project = project,
+                listOf(
+                    NotificationAction.create(
+                        message("codewhisperer.actions.open_settings.title")
+                    ) { _, notification ->
+                        ShowSettingsUtil.getInstance().showSettingsDialog(project, message("aws.settings.codewhisperer.configurable.title"))
+                    },
+                    NotificationAction.create(
+                        message("codewhisperer.notification.custom.simple.button.got_it")
+                    ) { _, notification -> notification.expire() }
+                )
+            )
+            return nodePath
+        }
+    }
+
+    /**
+     * Locates node executable ≥18 in system PATH.
+     * Uses IntelliJ's PathEnvironmentVariableUtil to find executables.
+     *
+     * @return Path? The absolute path to node ≥18 if found, null otherwise
+     */
+    private fun locateNodeCommand(): Path? {
+        val exeName = if (SystemInfo.isWindows) "node.exe" else "node"
+
+        return PathEnvironmentVariableUtil.findAllExeFilesInPath(exeName)
+            .asSequence()
+            .map { it.toPath() }
+            .filter { Files.isRegularFile(it) && Files.isExecutable(it) }
+            .firstNotNullOfOrNull { path ->
+                try {
+                    val process = ProcessBuilder(path.toString(), "--version")
+                        .redirectErrorStream(true)
+                        .start()
+
+                    if (!process.waitFor(2, TimeUnit.SECONDS)) {
+                        process.destroy()
+                        null
+                    } else if (process.exitValue() == 0) {
+                        val version = process.inputStream.bufferedReader().readText().trim()
+                        val majorVersion = version.removePrefix("v").split(".")[0].toIntOrNull()
+
+                        if (majorVersion != null && majorVersion >= 18) {
+                            path.toAbsolutePath()
+                        } else {
+                            LOG.debug { "Node version < 18 found at: $path (version: $version)" }
+                            null
+                        }
+                    } else {
+                        LOG.debug { "Failed to get version from node at: $path" }
+                        null
+                    }
+                } catch (e: Exception) {
+                    LOG.debug(e) { "Failed to check version for node at: $path" }
+                    null
+                }
+            }
+    }
+
     override fun dispose() {
         if (!launcherFuture.isDone) {
             try {

plugins/amazonq/shared/jetbrains-community/src/software/aws/toolkits/jetbrains/settings/LspSettings.kt

@@ -25,15 +25,22 @@ class LspSettings : PersistentStateComponent<LspConfiguration> {
 
     fun getArtifactPath() = state.artifactPath
 
+    fun getNodeRuntimePath() = state.nodeRuntimePath
+
     fun setArtifactPath(artifactPath: String?) {
         state.artifactPath = artifactPath.nullize(nullizeSpaces = true)
     }
 
+    fun setNodeRuntimePath(nodeRuntimePath: String?) {
+        state.nodeRuntimePath = nodeRuntimePath.nullize(nullizeSpaces = true)
+    }
+
     companion object {
         fun getInstance(): LspSettings = service()
     }
 }
 
 class LspConfiguration : BaseState() {
     var artifactPath by string()
+    var nodeRuntimePath by string()
 }

plugins/core/resources/resources/software/aws/toolkits/resources/MessagesBundle.properties

@@ -146,6 +146,8 @@ amazonqFeatureDev.placeholder.downloading_and_extracting_lsp_artifacts=Downloadi
 amazonqFeatureDev.placeholder.generating_code=Generating code...
 amazonqFeatureDev.placeholder.lsp=LSP
 amazonqFeatureDev.placeholder.new_plan=Describe your task or issue in as much detail as possible
+amazonqFeatureDev.placeholder.node_runtime_message=Please provide the absolute path of your node js v18+ runtime executable in Settings. Re-open IDE to apply this change.
+amazonqFeatureDev.placeholder.node_runtime_path=Node Runtime Path
 amazonqFeatureDev.placeholder.provide_code_feedback=Provide feedback or comments
 amazonqFeatureDev.placeholder.select_lsp_artifact=Select LSP Artifact
 amazonqFeatureDev.placeholder.write_new_prompt=Write a new prompt