Add software acknowledgments, link to them from About window

scripts/generate-acknowledgments.js

@@ -0,0 +1,109 @@
+/* eslint-disable no-console */
+const assert = require('assert');
+const fs = require('fs');
+const { join } = require('path');
+const pMap = require('p-map');
+const prettier = require('prettier');
+
+const {
+  dependencies = {},
+  optionalDependencies = {},
+} = require('../package.json');
+
+const SKIPPED_DEPENDENCIES = new Set(['ringrtc', 'zkgroup']);
+
+const rootDir = join(__dirname, '..');
+const nodeModulesPath = join(rootDir, 'node_modules');
+const destinationPath = join(rootDir, 'ACKNOWLEDGMENTS.md');
+
+function isLicenseFileName(fileName) {
+  return /^licen[s|c]e/i.test(fileName);
+}
+
+async function getMarkdownForDependency(dependencyName) {
+  let licenseBody;
+
+  // fs-xattr is an optional dependency that may fail to install (on Windows, most
+  //   commonly), so we have a special case for it here. We may need to do something
+  //   similar for new optionalDependencies in the future.
+  if (dependencyName === 'fs-xattr') {
+    licenseBody = 'License: MIT';
+  } else {
+    const dependencyRootPath = join(nodeModulesPath, dependencyName);
+
+    const licenseFileName = (
+      await fs.promises.readdir(dependencyRootPath)
+    ).find(isLicenseFileName);
+
+    if (licenseFileName) {
+      const licenseFilePath = join(dependencyRootPath, licenseFileName);
+      licenseBody = (
+        await fs.promises.readFile(licenseFilePath, 'utf8')
+      ).trim();
+    } else {
+      const packageJsonPath = join(dependencyRootPath, 'package.json');
+      const { license } = JSON.parse(
+        await fs.promises.readFile(packageJsonPath)
+      );
+      if (!license) {
+        throw new Error(`Could not find license for ${dependencyName}`);
+      }
+      licenseBody = `License: ${license}`;
+    }
+  }
+
+  return [
+    `## ${dependencyName}`,
+    '',
+    ...licenseBody.split(/\r?\n/).map(line => {
+      const trimmed = line.trim();
+      if (trimmed) {
+        return `    ${trimmed}`;
+      }
+      return trimmed;
+    }),
+  ].join('\n');
+}
+
+async function main() {
+  assert.deepStrictEqual(
+    Object.keys(optionalDependencies),
+    ['fs-xattr'],
+    'Unexpected optionalDependencies when generating acknowledgments file. To ensure that this file is generated deterministically, make sure to special-case it the acknowledgments generation script.'
+  );
+
+  const dependencyNames = [
+    ...Object.keys(dependencies),
+    ...Object.keys(optionalDependencies),
+  ]
+    .filter(name => !SKIPPED_DEPENDENCIES.has(name))
+    .sort();
+
+  const markdownsForDependency = await pMap(
+    dependencyNames,
+    getMarkdownForDependency,
+    // Without this, we may run into "too many open files" errors.
+    { concurrency: 100 }
+  );
+
+  const unformattedOutput = [
+    '# Acknowledgments',
+    '',
+    'Signal Desktop makes use of the following open source projects.',
+    '',
+    markdownsForDependency.join('\n\n'),
+  ].join('\n');
+
+  const prettierConfig = await prettier.resolveConfig(destinationPath);
+  const output = prettier.format(unformattedOutput, {
+    ...prettierConfig,
+    filepath: destinationPath,
+  });
+
+  await fs.promises.writeFile(destinationPath, output);
+}
+
+main().catch(err => {
+  console.error(err);
+  process.exit(1);
+});