feat(ncu-config): add support for partially encrypted config files

bin/ncu-config.js

@@ -1,10 +1,14 @@
 #!/usr/bin/env node
 
+import * as readline from 'node:readline/promises';
+import { stdin as input, stdout as output } from 'node:process';
+
 import yargs from 'yargs';
 import { hideBin } from 'yargs/helpers';
 
 import {
-  getConfig, updateConfig, GLOBAL_CONFIG, PROJECT_CONFIG, LOCAL_CONFIG
+  getConfig, updateConfig, GLOBAL_CONFIG, PROJECT_CONFIG, LOCAL_CONFIG,
+  encryptValue
 } from '../lib/config.js';
 import { setVerbosityFromEnv } from '../lib/verbosity.js';
 
@@ -13,10 +17,15 @@ setVerbosityFromEnv();
 const args = yargs(hideBin(process.argv))
   .completion('completion')
   .command({
-    command: 'set <key> <value>',
+    command: 'set <key> [<value>]',
     desc: 'Set a config variable',
     builder: (yargs) => {
       yargs
+        .option('encrypt', {
+          describe: 'Store the value encrypted using gpg',
+          alias: 'x',
+          type: 'boolean'
+        })
         .positional('key', {
           describe: 'key of the configuration',
           type: 'string'
@@ -61,8 +70,6 @@ const args = yargs(hideBin(process.argv))
   .conflicts('global', 'project')
   .help();
 
-const argv = args.parse();
-
 function getConfigType(argv) {
   if (argv.global) {
     return { configName: 'global', configType: GLOBAL_CONFIG };
@@ -73,9 +80,19 @@ function getConfigType(argv) {
   return { configName: 'local', configType: LOCAL_CONFIG };
 }
 
-function setHandler(argv) {
+async function setHandler(argv) {
   const { configName, configType } = getConfigType(argv);
   const config = getConfig(configType);
+  if (!argv.value) {
+    const rl = readline.createInterface({ input, output });
+    argv.value = await rl.question('What value do you want to set? ');
+    rl.close();
+  } else if (argv.encrypt) {
+    console.warn('Passing sensitive config value via the shell is discouraged');
+  }
+  if (argv.encrypt) {
+    argv.value = await encryptValue(argv.value);
+  }
   console.log(
     `Updating ${configName} configuration ` +
     `[${argv.key}]: ${config[argv.key]} -> ${argv.value}`);
@@ -96,6 +113,8 @@ function listHandler(argv) {
   }
 }
 
+const argv = await args.parse();
+
 if (!['get', 'set', 'list'].includes(argv._[0])) {
   args.showHelp();
 }

lib/auth.js

@@ -3,7 +3,7 @@ import { ClientRequest } from 'node:http';
 
 import ghauth from 'ghauth';
 
-import { clearCachedConfig, getMergedConfig, getNcurcPath } from './config.js';
+import { clearCachedConfig, encryptValue, getMergedConfig, getNcurcPath } from './config.js';
 
 export default lazy(auth);
 
@@ -83,7 +83,12 @@ async function auth(
         'see https://github.com/nodejs/node-core-utils/blob/main/README.md.\n');
       const credentials = await tryCreateGitHubToken(githubAuth);
       username = credentials.user;
-      token = credentials.token;
+      try {
+        token = await encryptValue(credentials.token);
+      } catch (err) {
+        console.warn('Failed encrypt token, storing unencrypted instead');
+        token = credentials.token;
+      }
       const json = JSON.stringify({ username, token }, null, 2);
       fs.writeFileSync(getNcurcPath(), json, {
         mode: 0o600 /* owner read/write */

lib/config.js

@@ -4,6 +4,7 @@ import os from 'node:os';
 import { readJson, writeJson } from './file.js';
 import { existsSync, mkdtempSync, rmSync } from 'node:fs';
 import { spawnSync } from 'node:child_process';
+import { forceRunAsync, runSync } from './run.js';
 
 export const GLOBAL_CONFIG = Symbol('globalConfig');
 export const PROJECT_CONFIG = Symbol('projectConfig');
@@ -32,6 +33,46 @@ export function clearCachedConfig() {
   mergedConfig = null;
 }
 
+export async function encryptValue(input) {
+  console.warn('Spawning gpg to encrypt the config value');
+  return forceRunAsync(
+    process.env.GPG_BIN || 'gpg',
+    ['--default-recipient-self', '--encrypt', '--armor'],
+    {
+      captureStdout: true,
+      ignoreFailure: false,
+      spawnArgs: { input }
+    }
+  );
+}
+
+function setOwnProperty(target, key, value) {
+  return Object.defineProperty(target, key, {
+    __proto__: null,
+    configurable: true,
+    enumerable: true,
+    value
+  });
+}
+function addEncryptedPropertyGetter(target, key, input) {
+  if (input?.startsWith?.('-----BEGIN PGP MESSAGE-----\n')) {
+    return Object.defineProperty(target, key, {
+      __proto__: null,
+      configurable: true,
+      get() {
+        console.warn(`The config value for ${key} is encrypted, spawning gpg to decrypt it...`);
+        const value = runSync(process.env.GPG_BIN || 'gpg', ['--decrypt'], { input });
+        setOwnProperty(target, key, value);
+        return value;
+      },
+      set(newValue) {
+        addEncryptedPropertyGetter(target, key, newValue) ||
+            setOwnProperty(target, key, newValue);
+      }
+    });
+  }
+}
+
 export function getConfig(configType, dir) {
   const configPath = getConfigPath(configType, dir);
   const encryptedConfigPath = configPath + '.gpg';
@@ -44,7 +85,11 @@ export function getConfig(configType, dir) {
     }
   }
   try {
-    return readJson(configPath);
+    const json = readJson(configPath);
+    for (const [key, val] of Object.entries(json)) {
+      addEncryptedPropertyGetter(json, key, val);
+    }
+    return json;
   } catch (cause) {
     throw new Error('Unable to parse config file ' + configPath, { cause });
   }

test/unit/auth.test.js

@@ -21,14 +21,16 @@ describe('auth', async function() {
   it('asks for auth data if no ncurc is found', async function() {
     await runAuthScript(
       undefined,
-      [FIRST_TIME_MSG, MOCKED_TOKEN]
+      [FIRST_TIME_MSG, MOCKED_TOKEN],
+      /^Spawning gpg to encrypt the config value\r?\nError: spawn do-not-exist ENOENT(?:.*\n)+Failed encrypt token, storing unencrypted instead\r?\n$/
     );
   });
 
   it('asks for auth data if ncurc is invalid json', async function() {
     await runAuthScript(
       { HOME: 'this is not json' },
-      [FIRST_TIME_MSG, MOCKED_TOKEN]
+      [FIRST_TIME_MSG, MOCKED_TOKEN],
+      /^Spawning gpg to encrypt the config value\r?\nError: spawn do-not-exist ENOENT(?:.*\n)+Failed encrypt token, storing unencrypted instead\r?\n$/
     );
   });
 
@@ -117,7 +119,7 @@ describe('auth', async function() {
 function runAuthScript(
   ncurc = {}, expect = [], error = '', fixture = 'run-auth-github') {
   return new Promise((resolve, reject) => {
-    const newEnv = { HOME: undefined, XDG_CONFIG_HOME: undefined };
+    const newEnv = { HOME: undefined, XDG_CONFIG_HOME: undefined, GPG_BIN: 'do-not-exist' };
     if (ncurc.HOME === undefined) ncurc.HOME = ''; // HOME must always be set.
     for (const envVar in ncurc) {
       if (ncurc[envVar] === undefined) continue;
@@ -154,8 +156,9 @@ function runAuthScript(
     });
     proc.on('close', () => {
       try {
-        assert.strictEqual(stderr, error);
-        assert.strictEqual(expect.length, 0);
+        if (typeof error === 'string') assert.strictEqual(stderr, error);
+        else assert.match(stderr, error);
+        assert.deepStrictEqual(expect, []);
         if (newEnv.HOME) {
           fs.rmSync(newEnv.HOME, { recursive: true, force: true });
         }