Add refactored handlers for initialize and the shutdown requests (spotify#15)

Author: rockbruno

Sources/SourceKitBazelBSP/RequestHandlers/InitializeHandler.swift

@@ -0,0 +1,162 @@
+// Copyright (c) 2025 Spotify AB.
+//
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+import BuildServerProtocol
+import Foundation
+import LanguageServerProtocol
+
+package let sourcekitBazelBSPVersion = "0.0.1"
+
+/// Handles the `initialize` request.
+///
+/// This is the first request that the LSP sends, and it contains the initial configuration
+/// for the server. We gather all information needed to operate the server, return it to the LSP,
+/// and then register the other handlers that will handle the rest of the requests.
+final class InitializeHandler {
+
+    private let baseConfig: BaseServerConfig
+    private let commandRunner: CommandRunner
+
+    private weak var connection: LSPConnection?
+
+    init(
+        baseConfig: BaseServerConfig,
+        commandRunner: CommandRunner = ShellCommandRunner(),
+        connection: LSPConnection? = nil,
+    ) {
+        self.baseConfig = baseConfig
+        self.commandRunner = commandRunner
+        self.connection = connection
+    }
+
+    func initializeBuild(
+        _ request: InitializeBuildRequest,
+        _ id: RequestID
+    ) throws -> InitializeBuildResponse {
+        let taskId = TaskId(id: "initializeBuild-\(id.description)")
+        connection?.startWorkTask(
+            id: taskId,
+            title: "Indexing: Initializing sourcekit-bazel-bsp"
+        )
+        do {
+            let initializedConfig = try makeInitializedConfig(
+                fromRequest: request,
+                baseConfig: baseConfig
+            )
+            let result = buildResponse(
+                fromRequest: request,
+                and: initializedConfig
+            )
+            connection?.finishTask(id: taskId, status: .ok)
+            return result
+        } catch {
+            connection?.finishTask(id: taskId, status: .error)
+            throw error
+        }
+    }
+
+    func makeInitializedConfig(
+        fromRequest request: InitializeBuildRequest,
+        baseConfig: BaseServerConfig,
+    ) throws -> InitializedServerConfig {
+        let rootUri = request.rootUri.arbitrarySchemeURL.path
+        logger.debug("rootUri: \(rootUri, privacy: .public)")
+        let regularOutputBase = URL(
+            fileURLWithPath: try commandRunner.bazel(
+                baseConfig: baseConfig,
+                rootUri: rootUri,
+                cmd: "info output_base"
+            )
+        )
+        logger.debug("regularOutputBase: \(regularOutputBase, privacy: .public)")
+
+        // Setup the special output base path where we will run indexing commands from.
+        let regularOutputBaseLastPath = regularOutputBase.lastPathComponent
+        let outputBase =
+            regularOutputBase
+            .deletingLastPathComponent()
+            .appendingPathComponent("\(regularOutputBaseLastPath)-sourcekit-bazel-bsp")
+            .path
+        logger.debug("outputBase: \(outputBase, privacy: .public)")
+
+        // Now, get the full output path based on the above output base.
+        let outputPath = try commandRunner.bazelIndexAction(
+            baseConfig: baseConfig,
+            outputBase: outputBase,
+            cmd: "info output_path",
+            rootUri: rootUri
+        )
+        logger.debug("outputPath: \(outputPath, privacy: .public)")
+
+        // Collecting the rest of the env's details
+        let devDir = try commandRunner.run("xcode-select --print-path")
+        let sdkRoot = try commandRunner.run("xcrun --sdk iphonesimulator --show-sdk-path")
+
+        return InitializedServerConfig(
+            baseConfig: baseConfig,
+            rootUri: rootUri,
+            outputBase: outputBase,
+            outputPath: outputPath,
+            devDir: devDir,
+            sdkRoot: sdkRoot
+        )
+    }
+
+    func buildResponse(
+        fromRequest request: InitializeBuildRequest,
+        and initializedConfig: InitializedServerConfig,
+    ) -> InitializeBuildResponse {
+        let capabilities = request.capabilities
+        let watchers: [FileSystemWatcher]?
+        let rootUri = initializedConfig.rootUri
+        if let filesToWatch = initializedConfig.baseConfig.filesToWatch {
+            watchers = filesToWatch.components(separatedBy: ",").map {
+                FileSystemWatcher(globPattern: rootUri + "/" + $0)
+            }
+        } else {
+            watchers = nil
+        }
+        return InitializeBuildResponse(
+            displayName: "sourcekit-bazel-bsp",
+            version: sourcekitBazelBSPVersion,
+            bspVersion: "2.2.0",
+            capabilities: BuildServerCapabilities(
+                compileProvider: .init(languageIds: capabilities.languageIds),
+                testProvider: .init(languageIds: capabilities.languageIds),
+                runProvider: .init(languageIds: capabilities.languageIds),
+                debugProvider: .init(languageIds: capabilities.languageIds),
+                inverseSourcesProvider: true,
+                dependencySourcesProvider: true,
+                resourcesProvider: true,
+                outputPathsProvider: false,  // FIXME: Not sure if we need this or not
+                buildTargetChangedProvider: true,
+                canReload: true,
+            ),
+            dataKind: InitializeBuildResponseDataKind.sourceKit,
+            data: SourceKitInitializeBuildResponseData(
+                indexDatabasePath: initializedConfig.indexDatabasePath,
+                indexStorePath: initializedConfig.indexStorePath,
+                outputPathsProvider: nil,  // FIXME: Not sure if we need this or not
+                prepareProvider: true,
+                sourceKitOptionsProvider: true,
+                watchers: watchers,
+            ).encodeToLSPAny()
+        )
+    }
+}

Sources/SourceKitBazelBSP/RequestHandlers/ShutdownHandler.swift

@@ -0,0 +1,58 @@
+// Copyright (c) 2025 Spotify AB.
+//
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+import BuildServerProtocol
+import Foundation
+import LanguageServerProtocol
+
+/// Handles the `build/shutdown` and `onBuildExit` messages.
+///
+/// According to the BSP spec, the server should first receive the `build/shutdown` request,
+/// and then the `onBuildExit` notification. We then exit with different codes depending on
+/// whether the LSP followed the spec correctly or not.
+final class ShutdownHandler {
+
+    private var didAskToShutdown = false
+    private var terminateHandler: ((Int32) -> Void)
+
+    init(terminateHandler: ((Int32) -> Void)? = nil) {
+        self.terminateHandler =
+            terminateHandler ?? { code in
+                safeTerminate(code)
+            }
+    }
+
+    func buildShutdown(
+        _ request: BuildShutdownRequest,
+        _ id: RequestID
+    ) throws -> VoidResponse {
+        didAskToShutdown = true
+        return VoidResponse()
+    }
+
+    func onBuildExit(_ notification: OnBuildExitNotification) throws {
+        terminateHandler(didAskToShutdown ? 0 : 1)
+    }
+}
+
+func safeTerminate(_ code: Int32) {
+    // Use _Exit to avoid running static destructors due to https://github.com/swiftlang/swift/issues/55112.
+    // (Copied from sourcekit-lsp)
+    _Exit(code)
+}

…Handlers/BuildTargetSourcesHandler.swift …ers/_old/BuildTargetSourcesHandler.swiftSources/SourceKitBazelBSP/MessageHandler/RequestHandlers/BuildTargetSourcesHandler.swift renamed to Sources/SourceKitBazelBSP/RequestHandlers/_old/BuildTargetSourcesHandler.swift Sources/SourceKitBazelBSP/MessageHandler/RequestHandlers/BuildTargetSourcesHandler.swift renamed to Sources/SourceKitBazelBSP/RequestHandlers/_old/BuildTargetSourcesHandler.swift

@@ -24,7 +24,7 @@ import Foundation
 /// Used to bootstrap the connection to sourcekit-lsp, so that later we can create the
 /// more complete `InitializedServerConfig` struct containing all information
 /// needed to operate the server.
-package struct BaseServerConfig {
+package struct BaseServerConfig: Equatable {
     let bazelWrapper: String
     let targets: [String]
     let indexFlags: [String]