added proxy config for complex proxy rules (#907)

* added proxy config for complex proxy rules

* fixed wrong proxy config value assignment and filtered match config

* added basic documentation for proxy-config

* fixed proxy config handling

* added first basic proxy config test

* added minmatch for glob matching

* fixed proxy config handling

* added proxy logging

* fixed proxy config test

* handled proxy all and config with hinting

* fixed proxyAll request handling

Author: i3ene

README.md

@@ -80,12 +80,14 @@ with the provided Dockerfile.
 |`-U` or `--utc` |Use UTC time format in log messages.| |
 |`--log-ip` |Enable logging of the client's IP address |`false` |
 |`-P` or `--proxy` |Proxies all requests which can't be resolved locally to the given url. e.g.: -P http://someurl.com | |
+|`--proxy-options` |Pass proxy [options](https://github.com/http-party/node-http-proxy#options) using nested dotted objects. e.g.: --proxy-options.secure false | |
+|`--proxy-config` |Pass in `.json` configuration file or stringified JSON. e.g.: `./path/to/config.json` | |
 |`--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 |
 |`--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` | 
+|`-C` or `--cert` |Path to ssl cert file |`cert.pem` |
 |`-K` or `--key` |Path to ssl key file |`key.pem` |
 |`-r` or `--robots` | Automatically provide a /robots.txt (The content of which defaults to `User-agent: *\nDisallow: /`)  | `false` |
 |`--no-dotfiles` |Do not show dotfiles| |

bin/http-server

@@ -67,6 +67,7 @@ if (argv.h || argv.help) {
     '  -P --proxy       Fallback proxy if the request cannot be resolved. e.g.: http://someurl.com',
     '  --proxy-all      Send every request to the proxy target instead of serving local files',
     '  --proxy-options  Pass options to proxy using nested dotted objects. e.g.: --proxy-options.secure false',
+    '  --proxy-config   Pass in .json configuration file. e.g.: ./path/to/config.json',
     '  --websocket      Enable websocket proxy',
     '',
     '  --user --username   Username for basic authentication [none]',
@@ -93,6 +94,7 @@ var port = argv.p || argv.port || parseInt(process.env.PORT, 10),
     sslPassphrase = process.env.NODE_HTTP_SERVER_SSL_PASSPHRASE,
     proxy = argv.P || argv.proxy,
     proxyOptions = argv['proxy-options'],
+    proxyConfig = argv['proxy-config'],
     websocket = argv.websocket,
     proxyAll = Boolean(argv['proxy-all']),
     utc = argv.U || argv.utc,
@@ -127,6 +129,12 @@ if (!argv.s && !argv.silent) {
           date, ip, chalk.red(req.method), chalk.red(req.url),
           chalk.red(error.status.toString()), chalk.red(error.message)
         );
+      }
+      else if (req.proxy) {
+        logger.info(
+          '[%s] %s "%s" (%s)-> "%s"',
+          date, ip, chalk.cyan(req.url), chalk.magenta('Proxy'), chalk.cyan(req.proxy.target)
+        );
       } else {
         logger.info(
           '[%s] %s "%s %s" "%s"',
@@ -174,6 +182,7 @@ function listen(port) {
     logFn: logger.request,
     proxy: proxy,
     proxyOptions: proxyOptions,
+    proxyConfig: proxyConfig,
     proxyAll: proxyAll,
     showDotfiles: argv.dotfiles,
     mimetypes: argv.mimetypes,
@@ -236,6 +245,38 @@ function listen(port) {
     }
   }
 
+  if (proxyConfig) {
+    try {
+      if (fs.existsSync(proxyConfig)) {
+        proxyConfig = fs.readFileSync(proxyConfig, 'utf8');
+      }
+      if (typeof proxyConfig === 'string') {
+        proxyConfig = JSON.parse(proxyConfig);
+      }
+      if (typeof proxyConfig !== 'object') {
+        throw new Error('Invalid proxy config');
+      }
+    }
+    catch (err) {
+      logger.info(chalk.red('Error: Invalid proxy config or file'));
+      process.exit(1);
+    }
+    // Proxy file overrides cli config
+    proxy = undefined;
+    proxyOptions = undefined;
+  }
+
+  if (proxyAll && proxyConfig) {
+    logger.info(chalk.red('Error: --proxy-all cannot be used with --proxy-config'));
+    logger.info(
+      '%s\n%s\n%s',
+      chalk.yellow('Hint: Use'),
+      chalk.cyan('"/**": {\n  "target": "your-proxy"\n}'),
+      chalk.yellow('in the proxy config to achieve the same effect.')
+    );
+    process.exit(1);
+  }
+
   if (proxyAll && !proxy) {
     logger.info(chalk.red('Error: --proxy-all requires --proxy to be set'));
     process.exit(1);

doc/http-server.1

@@ -123,6 +123,10 @@ Requires \-\-proxy.
 .BI \-\-proxy\-options
 Pass proxy options using nested dotted objects.
 
+.TP
+.BI \-\-proxy\-config
+Pass in .json configuration file.
+
 .TP
 .BI \-\-user ", " \-\-username " " \fIUSERNAME\fR
 Username for basic authentication.

lib/http-server.js

@@ -7,6 +7,7 @@ var fs = require('fs'),
   httpProxy = require('http-proxy'),
   corser = require('corser'),
   secureCompare = require('secure-compare');
+var { minimatch } = require('minimatch');
 
 //
 // Remark: backwards compatibility for previous
@@ -154,6 +155,43 @@ function HttpServer(options) {
     });
   }
 
+  if (typeof options.proxyConfig === 'object') {
+    var proxy = httpProxy.createProxyServer();
+    before.push(function (req, res, next) {
+      for (var key of Object.keys(options.proxyConfig)) {
+        if (!minimatch(req.url, key)) continue;
+        req.proxy ??= {};
+        var matchConfig = options.proxyConfig[key];
+        
+        if (matchConfig.pathRewrite) {
+          Object.entries(matchConfig.pathRewrite).forEach(rewrite => {
+            req.url = req.url.replace(new RegExp(rewrite[0]), rewrite[1]);
+          });
+        }
+        
+        var configEntries = Object.entries(matchConfig).filter(entry => entry[0] !== "pathRewrite");
+        configEntries.forEach(entry => req.proxy[entry[0]] = entry[1]);
+        break;
+      }
+
+      if (req.proxy) {
+        if (options.logFn) {
+          options.logFn(req, res);
+        }
+        proxy.web(req, res, req.proxy, function (err, req, res) {
+          if (options.logFn) {
+            options.logFn(req, res, {
+              message: err.message,
+              status: res.statusCode });
+          }
+          res.emit('next');
+        });
+      } else {
+        next();
+      }
+    });
+  }
+
   if (!proxyAll) {
     before.push(httpServerCore({
       root: this.root,