Support debug build

.vscode/launch.json

@@ -17,7 +17,7 @@
         "<node_internals>/**/*.js"
       ],
       "env": {
-        "SERVER_PATH": "${workspaceFolder}/target/debug/fluent-bit-language-server"
+        "__FLB_LSP_SERVER_DEBUG": "${workspaceFolder}/target/debug/fluent-bit-language-server"
       }
     }
   ]

clients/vscode/src/bootstrap.ts

@@ -0,0 +1,67 @@
+import * as vscode from "vscode";
+import * as os from "os";
+
+export async function bootstrap(
+  context: vscode.ExtensionContext
+): Promise<string> {
+  const path = await getServers(context);
+  if (!path) {
+    throw new Error("fluent-bit-language-server is not available.");
+  }
+
+  console.log("Using server binary at", path);
+
+  // TODO: check validity
+
+  return path;
+}
+
+async function getServers(
+  context: vscode.ExtensionContext
+): Promise<string | undefined> {
+  // check if the server path is configured explicitly
+  const explicitPath = process.env["__FLB_LSP_SERVER_DEBUG"];
+  if (explicitPath) {
+    if (explicitPath.startsWith("~/")) {
+        return os.homedir() + explicitPath.slice("~".length);
+    }
+    return explicitPath;
+  }
+
+  const ext = process.platform === "win32" ? ".exe" : "";
+  const bundled = vscode.Uri.joinPath(context.extensionUri, "server", `fluent-bit-language-server${ext}`);
+  const bundledExists = await fileExists(bundled);
+
+  if (!bundledExists) {
+    await vscode.window.showErrorMessage(
+      "Unfortunately we don't ship binaries for your platform yet. " +
+      "Please build and run the server manually from the source code. " +
+      "Or, please create an issue on repository."
+    );
+    return;
+  }
+}
+
+async function fileExists(uri: vscode.Uri) {
+  return await vscode.workspace.fs.stat(uri).then(
+    () => true,
+    () => false,
+  );
+}
+
+// TODO
+// export function isValidExecutable(path: string, extraEnv: Env): boolean {
+//   log.debug("Checking availability of a binary at", path);
+
+//   const res = spawnSync(path, ["--version"], {
+//       encoding: "utf8",
+//       env: { ...process.env, ...extraEnv },
+//   });
+
+//   if (res.error) {
+//       log.warn(path, "--version:", res);
+//   } else {
+//       log.info(path, "--version:", res);
+//   }
+//   return res.status === 0;
+// }

clients/vscode/src/main.ts

@@ -9,31 +9,15 @@ import {
   LanguageClientOptions,
   ServerOptions,
 } from "vscode-languageclient/node";
-import * as vscode from "vscode";
+import { bootstrap } from "./bootstrap";
 
 let client: LanguageClient;
 
 export async function activate(context: ExtensionContext) {
-  // TODO: bootstrap debug, release
-  // const traceOutputChannel = window.createOutputChannel("fluent-bit language server trace");
-  // const command = process.env.SERVER_PATH || "fluent-bit-language-server";
-
-  // Use bundled server only for now
-  const ext = process.platform === "win32" ? ".exe" : "";
-  const bundled = vscode.Uri.joinPath(context.extensionUri, "server", `fluent-bit-language-server${ext}`);
-  const bundledExists = await fileExists(bundled);
-
-  if (!bundledExists) {
-    await vscode.window.showErrorMessage(
-      "Unfortunately we don't ship binaries for your platform yet." +
-      "Please build and run the server manually from the source code." +
-      "Or, please create an issue on repository."
-    );
-    return;
-  }
+  const path = await bootstrap(context);
 
   const run: Executable = {
-    command: bundled.fsPath,
+    command: path,
     options: {
       env: {
         ...process.env
@@ -70,13 +54,6 @@ export async function activate(context: ExtensionContext) {
   await client.start();
 }
 
-async function fileExists(uri: vscode.Uri) {
-  return await vscode.workspace.fs.stat(uri).then(
-    () => true,
-    () => false,
-  );
-}
-
 export function deactivate(): Thenable<void> | undefined {
   if (!client) {
     return undefined;

fluent-bit-language-server/src/main.rs

@@ -21,5 +21,7 @@ async fn main() {
     })
     .finish();
 
+    // TODO: support other commands (e.g. `--version`)
+
     Server::new(stdin, stdout, socket).serve(service).await;
 }