Merge pull request #126 from gadget-inc/fix-atomic-write

Write files to disk atomically so they are never empty

Author: airhorns

package.json

@@ -45,6 +45,7 @@
     "globby": "^11.1.0",
     "lodash": "^4.17.20",
     "pkg-dir": "^5.0.0",
+    "write-file-atomic": "^6.0.0",
     "yargs": "^16.2.0"
   },
   "devDependencies": {
@@ -55,6 +56,7 @@
     "@types/jest": "^27.4.0",
     "@types/lodash": "^4.14.194",
     "@types/node": "^18.11.9",
+    "@types/write-file-atomic": "^4.0.3",
     "@types/yargs": "^15.0.14",
     "eslint": "^8.40.0",
     "eslint-plugin-jest": "^27.2.1",

pnpm-lock.yaml

@@ -1,4 +1,5 @@
 import type { Config, Options } from "@swc/core";
+import writeFileAtomic from "write-file-atomic";
 import { transformFile } from "@swc/core";
 import findRoot from "find-root";
 import * as fs from "fs/promises";
@@ -163,7 +164,7 @@ export class SwcCompiler implements Compiler {
 
     const destination = path.join(this.outDir, filename).replace(this.workspaceRoot, "");
     await fs.mkdir(path.dirname(destination), { recursive: true });
-    await fs.writeFile(destination, output.code);
+    await writeFileAtomic(destination, output.code);
     const file = { filename, root, destination, config };
 
     this.compiledFiles.addFile(file);

src/SwcCompiler.ts

@@ -1,7 +1,7 @@
 // have to use a module import like this so we can re-access imported properties as they might change, see https://github.com/nodejs/node/issues/36531
 import { promises as fs } from "fs";
 import type { MessagePort } from "worker_threads";
-import workerThreads, { MessageChannel, receiveMessageOnPort, Worker } from "worker_threads";
+import workerThreads, { MessageChannel, receiveMessageOnPort, threadId, Worker } from "worker_threads";
 import { log } from "./utils";
 
 log.debug("syncworker file boot", { isMainThread: workerThreads.isMainThread, hasWorkerData: !!workerThreads.workerData });
@@ -52,7 +52,7 @@ export class SyncWorker {
       transferList: [port2],
     });
 
-    log.debug("booted syncworker worker", { filename: __filename, scriptPath, threadId: this.worker.threadId });
+    log.debug("booted syncworker worker", { filename: __filename, scriptPath, childWorkerThreadId: this.worker.threadId });
 
     this.worker.on("error", (error) => {
       log.error("[wds] Internal error", error);
@@ -82,7 +82,7 @@ export class SyncWorker {
 
     const sharedBufferView = new Int32Array(call.sharedBuffer);
 
-    log.debug("calling syncworker", call);
+    log.debug("calling syncworker", { thisThreadId: threadId, childWorkerThreadId: this.worker.threadId, call });
     this.port.postMessage(call);
 
     // synchronously wait for worker thread to get back to us

src/SyncWorker.ts

@@ -2,8 +2,9 @@ import { promises as fs } from "fs";
 import { defaults } from "lodash";
 import path from "path";
 import type { ProjectConfig } from "./Options";
+import { threadId } from "worker_threads";
 
-const logPrefix = `[wds pid=${process.pid}]`;
+const logPrefix = `[wds pid=${process.pid} thread=${threadId}]`;
 export const log = {
   debug: (...args: any[]) => process.env["WDS_DEBUG"] && console.warn(logPrefix, ...args),
   info: (...args: any[]) => console.warn(logPrefix, ...args),