fix: fail fast on --password without --user (#937)

* fix: fail fast on `--password` without `--user`

When passing a password without a username, http-server will launch
successfully but the first request with an Authorization header will
crash the server. This behavior is very inconvenient. This commit makes
it fail fast instead so you know there's a problem before you log out of
SSH or walk out of the house or office. Also alised `--user` to
`--username` for added convenience.

Resolves #935

* doc: update documentation for `--username` flag

Author: KernelDeimos

README.md

@@ -81,7 +81,7 @@ with the provided Dockerfile.
 |`-P` or `--proxy` |Proxies all requests which can't be resolved locally to the given url. e.g.: -P http://someurl.com | |
 |`--proxy-all` |Forward every request to the proxy target instead of serving local files|`false`|
 |`--proxy-options` |Pass proxy [options](https://github.com/http-party/node-http-proxy#options) using nested dotted objects. e.g.: --proxy-options.secure false |
-|`--username` |Username for basic authentication | |
+|`--user` or `--username` |Username for basic authentication | |
 |`--password` |Password for basic authentication | |
 |`-S`, `--tls` or `--ssl` |Enable secure request serving with TLS/SSL (HTTPS)|`false`|
 |`-C` or `--cert` |Path to ssl cert file |`cert.pem` | 

bin/http-server

@@ -13,7 +13,8 @@ var chalk     = require('chalk'),
 var argv = require('minimist')(process.argv.slice(2), {
   alias: {
     tls: 'ssl',
-    header: 'H'
+    header: 'H',
+    user: 'username',
   },
   boolean: ['proxy-all']
 });
@@ -68,8 +69,8 @@ if (argv.h || argv.help) {
     '  --proxy-options  Pass options to proxy using nested dotted objects. e.g.: --proxy-options.secure false',
     '  --websocket      Enable websocket proxy',
     '',
-    '  --username   Username for basic authentication [none]',
-    '               Can also be specified with the env variable NODE_HTTP_SERVER_USERNAME',
+    '  --user --username   Username for basic authentication [none]',
+    '                      Can also be specified with the env variable NODE_HTTP_SERVER_USERNAME',
     '  --password   Password for basic authentication [none]',
     '               Can also be specified with the env variable NODE_HTTP_SERVER_PASSWORD',
     '',

doc/http-server.1

@@ -118,7 +118,7 @@ Requires \-\-proxy.
 Pass proxy options using nested dotted objects.
 
 .TP
-.BI \-\-username " " \fIUSERNAME\fR
+.BI \-\-user ", " \-\-username " " \fIUSERNAME\fR
 Username for basic authentication.
 Can also be specified with the environment variable NODE_HTTP_SERVER_USERNAME.
 Defaults to none.

lib/http-server.js

@@ -93,6 +93,10 @@ function HttpServer(options) {
   }
 
   if (options.username || options.password) {
+    if (!options.username || !options.password) {
+      throw new Error('Basic authentication requires both username and password to be specified');
+    }
+
     before.push(function (req, res) {
       var credentials = auth(req);