Add option to pass a proxy

If specified the --proxy option is used as a fallback route handler.

This can be used to run lambdas and a website under the same hostname/port locally.

Author: Iain Collins

README.md

@@ -87,4 +87,5 @@ Here's is a list of the things that happen when `now-lambda` process your `now.j
 ## CLI arguments
 
 * `--config` - path to `now.json` file
-* `--port` - by default the local server listens on port 8004. You can change it via this argument.
+* `--port` - by default the local server listens on port 8004. You can change it via this argument.
+* `--proxy` - a URL to use as a fallback proxy for requests that would otherwise fail (e.g. `http://localhost:3000`)

index.js

@@ -8,7 +8,8 @@ const yargs = require('yargs');
 const NamedRegExp = require('named-regexp-groups');
 const cors = require('cors');
 const extglob = require('extglob');
-const mime = require('mime-types')
+const mime = require('mime-types');
+const request = require('request');
 
 const argv = yargs
   .options({
@@ -21,7 +22,12 @@ const argv = yargs
       type: 'number',
       default: 8004,
       desc: 'The port where the runner is listening for your requests'
-    }
+    },
+    proxy: {
+      type: 'string',
+      default: null,
+      desc: 'A URL to use as a fallback proxy for requests that would otherwise fail (e.g. "http://localhost:3000")'
+    },
   })
   .help()
   .argv;
@@ -132,11 +138,23 @@ if (fs.existsSync(nowConfPath)) {
 
         delete require.cache[require.resolve(handlerFilepath)];
       } else if (fs.existsSync(handlerFilepath)) {
-        console.log(logMessage.join('\n'));
-        sendFile(res, handlerFilepath);
+        if (argv.proxy) {
+          const proxy = request(`${argv.proxy}${req.url}`)
+          req.pipe(proxy)
+          proxy.pipe(res)
+        } else {
+          console.log(logMessage.join('\n'));
+          sendFile(res, handlerFilepath);
+        }
       } else {
-        res.statusCode = 404;
-        res.end(handlerFilepath + ' can not be found.');
+        if (argv.proxy) {
+          const proxy = request(`${argv.proxy}${req.url}`)
+          req.pipe(proxy)
+          proxy.pipe(res)
+        } else {
+          res.statusCode = 404;
+          res.end(handlerFilepath + ' can not be found.');
+        }
       }
     };
 
@@ -158,4 +176,4 @@ if (fs.existsSync(nowConfPath)) {
   });
 } else {
   error('now.json can not be found in ' + nowConfPath);
-}
+}

package.json

@@ -1,6 +1,6 @@
 {
   "name": "now-lambda-runner",
-  "version": "3.3.0",
+  "version": "3.4.0",
   "bin": {
     "now-lambda": "./index.js"
   },
@@ -28,6 +28,7 @@
     "extglob": "3.0.0",
     "mime-types": "2.1.21",
     "named-regexp-groups": "^1.0.3",
+    "request": "^2.88.0",
     "yargs": "12.0.5"
   }
 }