anchor/cli/npm-package/anchor.js

#!/usr/bin/env node
const { spawn, spawnSync } = require("child_process");
const path = require("path");
const { arch, platform } = require("os");
const { version } = require("./package.json");

const PACKAGE_VERSION = `anchor-cli ${version}`;
const PACKAGE_ANCHOR_PATH = path.join(__dirname, "anchor");

function getBinaryVersion(location) {
  const result = spawnSync(location, ["--version"]);
  const error =
    (result.error && result.error.toString()) ||
    (result.stderr.length > 0 && result.stderr.toString().trim()) ||
    null;
  return [error, result.stdout && result.stdout.toString().trim()];
}

function runAnchor(location) {
  const args = process.argv.slice(2);
  const anchor = spawn(location, args, { stdio: "inherit" });
  anchor.on("exit", (code, signal) => {
    process.on("exit", () => {
      if (signal) {
        process.kill(process.pid, signal);
      } else {
        process.exit(code);
      }
    });
  });

  process.on("SIGINT", function () {
    anchor.kill("SIGINT");
    anchor.kill("SIGTERM");
  });
}

function tryPackageAnchor() {
  if (arch() !== "x64" || platform() !== "linux") {
    console.error(`Only x86_64 / Linux distributed in NPM package right now.`);
    return false;
  }

  const [error, binaryVersion] = getBinaryVersion(PACKAGE_ANCHOR_PATH);
  if (error !== null) {
    console.error(`Failed to get version of local binary: ${error}`);
    return false;
  }
  if (binaryVersion !== PACKAGE_VERSION) {
    console.error(
      `Package binary version is not correct. Expected "${PACKAGE_VERSION}", found "${binaryVersion}".`
    );
    return false;
  }

  runAnchor(PACKAGE_ANCHOR_PATH);
  return true;
}

function trySystemAnchor() {
  console.error("Trying globally installed anchor.");

  const added = path.dirname(process.argv[1]);
  const directories = process.env.PATH.split(":").filter(
    (dir) => dir !== added
  );
  process.env.PATH = directories.join(":");

  const [error, binaryVersion] = getBinaryVersion("anchor");
  if (error !== null) {
    console.error(`Failed to get version of global binary: ${error}`);
    return;
  }
  if (binaryVersion !== PACKAGE_VERSION) {
    console.error(
      `Globally installed anchor version is not correct. Expected "${PACKAGE_VERSION}", found "${binaryVersion}".`
    );
    return;
  }

  runAnchor("anchor");
}

tryPackageAnchor() || trySystemAnchor();