feat: add unix domain socket utils (#110)

Author: pi0

README.md

@@ -22,6 +22,9 @@ import {
   checkPort,
   getRandomPort,
   waitForPort,
+  getSocketAddress,
+  isSocketSupported,
+  cleanSocket
 } from "get-port-please";
 
 // CommonJS
@@ -30,6 +33,9 @@ const {
   checkPort,
   getRandomPort,
   waitForPort,
+  getSocketAddress,
+  isSocketSupported,
+  cleanSocket
 } = require("get-port-please");
 ```
 

src/index.ts

@@ -1,3 +1,4 @@
 export * from "./types";
 export * from "./get-port";
 export * from "./unsafe-ports";
+export * from "./socket";

src/socket.ts

@@ -0,0 +1,95 @@
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { Server } from "node:net";
+import { rm } from "node:fs/promises";
+
+export interface GetSocketOptions {
+  /* Human readable prefix for the socket name */
+  name: string;
+
+  /**
+   * Use process ID in the socket name.
+   */
+  pid?: boolean;
+
+  /**
+   * Use a random number in the socket name.
+   *
+   */
+  random?: boolean;
+}
+
+let _nodeMajorVersion: number | undefined;
+let _isSocketSupported: boolean | undefined;
+
+/**
+ * Generates a socket address based on the provided options.
+ */
+export function getSocketAddress(opts: GetSocketOptions): string {
+  const parts = [
+    opts.name,
+    opts.pid ? process.pid : undefined,
+    opts.random ? Math.round(Math.random() * 10_000) : undefined,
+  ].filter(Boolean);
+
+  const socketName = `${parts.join("-")}.sock`;
+
+  // Windows: pipe
+  if (process.platform === "win32") {
+    return join(String.raw`\\.\pipe`, socketName);
+  }
+
+  // Linux: abstract namespace
+  // Fallback to a regular file socket on older Node.js versions to avoid issues
+  if (process.platform === "linux") {
+    if (_nodeMajorVersion === undefined) {
+      _nodeMajorVersion = +process.versions.node.split(".")[0];
+    }
+    if (_nodeMajorVersion >= 20) {
+      return `\0${socketName}`;
+    }
+  }
+
+  // Unix socket
+  return join(tmpdir(), socketName);
+}
+
+/**
+ * Test if the current environment supports sockets.
+ */
+export async function isSocketSupported(): Promise<boolean> {
+  if (_isSocketSupported !== undefined) {
+    return _isSocketSupported;
+  }
+  if (globalThis.process?.versions?.webcontainer) {
+    // Seems broken: https://stackblitz.com/edit/stackblitz-starters-1y68uhvu
+    return false;
+  }
+
+  const socketAddress = getSocketAddress({ name: "get-port", random: true });
+  const server = new Server();
+  try {
+    await new Promise<void>((resolve, reject) => {
+      server.on("error", reject);
+      server.listen(socketAddress, resolve);
+    });
+    _isSocketSupported = true;
+    return true;
+  } catch {
+    _isSocketSupported = false;
+    return false;
+  } finally {
+    if (server.listening) {
+      server.close();
+      await cleanSocket(socketAddress);
+    }
+  }
+}
+
+export async function cleanSocket(path: string): Promise<void> {
+  if (!path || path[0] === "\0" || path.startsWith(String.raw`\\.\pipe`)) {
+    // Abstract namespace sockets or invalid paths
+    return;
+  }
+  return rm(path, { force: true, recursive: true }).catch(console.error);
+}

test/socket.test.ts

@@ -0,0 +1,12 @@
+import { describe, test, expect } from "vitest";
+import { isSocketSupported, getSocketAddress } from "../src";
+
+describe("socket", () => {
+  test("isSocketSupported", async () => {
+    expect(await isSocketSupported()).toBe(true);
+  });
+  test("getSocketAddress", async () => {
+    const addr = getSocketAddress({ name: "test", pid: true, random: true });
+    expect(addr).toMatch(/test-\d+-\d+\.sock/);
+  });
+});