fix: allow _auth to be set via environment

When using legacy auth, the env var `NPM_CONFIG__AUTH` can be used.

Fixes #324

Author: shaneog

README.md

@@ -53,9 +53,10 @@ Both the [token](https://docs.npmjs.com/getting-started/working_with_tokens) and
 | `NPM_USERNAME`          | Npm username created via [npm adduser](https://docs.npmjs.com/cli/adduser) or on [npmjs.com](https://www.npmjs.com)           |
 | `NPM_PASSWORD`          | Password of the npm user.                                                                                                     |
 | `NPM_EMAIL`             | Email address associated with the npm user                                                                                    |
-| `NPM_CONFIG_USERCONFIG` | Path to non-default .npmrc file                                                                                                 |
+| `NPM_CONFIG_USERCONFIG` | Path to non-default .npmrc file                                                                                               |
+| `NPM_CONFIG__AUTH`      | Npm `_auth` configuration parameter set as an [environment variable](https://docs.npmjs.com/cli/v7/using-npm/config)          |
 
-Use either `NPM_TOKEN` for token authentication or `NPM_USERNAME`, `NPM_PASSWORD` and `NPM_EMAIL` for legacy authentication
+Use either `NPM_TOKEN` for token authentication or `NPM_USERNAME`, `NPM_PASSWORD` and `NPM_EMAIL` (or alternatively `NPM_CONFIG__AUTH` and `NPM_EMAIL`) for legacy authentication
 
 ### Options
 

lib/set-npmrc-auth.js

@@ -9,7 +9,7 @@ const getError = require('./get-error');
 module.exports = async (
   npmrc,
   registry,
-  {cwd, env: {NPM_TOKEN, NPM_CONFIG_USERCONFIG, NPM_USERNAME, NPM_PASSWORD, NPM_EMAIL}, logger}
+  {cwd, env: {NPM_TOKEN, NPM_CONFIG__AUTH, NPM_CONFIG_USERCONFIG, NPM_USERNAME, NPM_PASSWORD, NPM_EMAIL}, logger}
 ) => {
   logger.log('Verify authentication for registry %s', registry);
   const {configs, ...rcConfig} = rc(
@@ -35,6 +35,12 @@ module.exports = async (
       `${currentConfig ? `${currentConfig}\n` : ''}_auth = \${LEGACY_TOKEN}\nemail = \${NPM_EMAIL}`
     );
     logger.log(`Wrote NPM_USERNAME, NPM_PASSWORD and NPM_EMAIL to ${npmrc}`);
+  } else if (NPM_CONFIG__AUTH && NPM_EMAIL) {
+    await outputFile(
+      npmrc,
+      `${currentConfig ? `${currentConfig}\n` : ''}_auth = \${NPM_CONFIG__AUTH}\nemail = \${NPM_EMAIL}`
+    );
+    logger.log(`Wrote NPM_CONFIG__AUTH and NPM_EMAIL to ${npmrc}`);
   } else if (NPM_TOKEN) {
     await outputFile(
       npmrc,

test/set-npmrc-auth.test.js

@@ -48,6 +48,19 @@ test.serial('Set auth with "NPM_USERNAME", "NPM_PASSWORD" and "NPM_EMAIL"', asyn
   t.deepEqual(t.context.log.args[1], [`Wrote NPM_USERNAME, NPM_PASSWORD and NPM_EMAIL to ${npmrc}`]);
 });
 
+test.serial('Set auth with "NPM_CONFIG__AUTH" and "NPM_EMAIL"', async (t) => {
+  process.env.HOME = tempy.directory();
+  const cwd = tempy.directory();
+  process.chdir(cwd);
+  const npmrc = tempy.file({name: '.npmrc'});
+  const env = {NPM_CONFIG__AUTH: 'npm_config__auth', NPM_EMAIL: 'npm_email'};
+
+  await require('../lib/set-npmrc-auth')(npmrc, 'http://custom.registry.com', {cwd, env, logger: t.context.logger});
+
+  t.is((await readFile(npmrc)).toString(), `_auth = \${NPM_CONFIG__AUTH}\nemail = \${NPM_EMAIL}`);
+  t.deepEqual(t.context.log.args[1], [`Wrote NPM_CONFIG__AUTH and NPM_EMAIL to ${npmrc}`]);
+});
+
 test.serial('Preserve home ".npmrc"', async (t) => {
   process.env.HOME = tempy.directory();
   const cwd = tempy.directory();
@@ -147,6 +160,22 @@ test.serial('Throw error if "NPM_TOKEN" is missing', async (t) => {
   t.is(error.code, 'ENONPMTOKEN');
 });
 
+test.serial('Throw error if "NPM_EMAIL" is missing when used with "NPM_CONFIG__AUTH"', async (t) => {
+  process.env.HOME = tempy.directory();
+  const cwd = tempy.directory();
+  process.chdir(cwd);
+  const npmrc = tempy.file({name: '.npmrc'});
+  const env = {NPM_CONFIG__AUTH: 'npm_config__auth'};
+
+  const [error] = await t.throwsAsync(
+    require('../lib/set-npmrc-auth')(npmrc, 'http://custom.registry.com', {cwd, env, logger: t.context.logger})
+  );
+
+  t.is(error.name, 'SemanticReleaseError');
+  t.is(error.message, 'No npm token specified.');
+  t.is(error.code, 'ENONPMTOKEN');
+});
+
 test.serial('Emulate npm config resolution if "NPM_CONFIG_USERCONFIG" is set', async (t) => {
   process.env.HOME = tempy.directory();
   const cwd = tempy.directory();