Merge pull request #1 from chetan1/master

Merge in Chetan's code

README.md

@@ -1 +1,23 @@
-## Coming soon!
+# Middleware for proxying and manipulating images
+
+This module allows you to manipulate and convert images on the fly.
+
+It provides:
+
+  * Resizing of images
+  * Conversion of images to grayscale
+  * Conversion of images into different formats
+
+
+## Installation
+
+    npm install connect-image-proxy
+
+
+## Usage
+
+  * Resize: hostname/route/?url=[url]&resize=1&height=[height]&width=[width]
+  * Grayscale: hostname/route/?url=[url]&grayscale=1
+  * Conversion [JPG, PNG, GIF]: hostname/route/?url=[url]&format=[format]
+  * Conversion + Grayscale + Resize: hostname/route/?url=[url]&format=png&grayscale=1&resize=1&height=[height]&width=[width]
+

examples/app.js

@@ -0,0 +1,20 @@
+var image_proxy = require('./../image-proxy');
+
+var express = require('express');
+var app = express.createServer();
+
+app.configure(function(){
+  app.set('view engine', 'jade');
+  app.set('views', __dirname + '/views');
+  app.set('view options', { layout: false, pretty: true});
+  app.use("/images", express.static(__dirname + '/public'));
+});
+
+
+app.get('/image', image_proxy.run);
+
+app.get('/test', function(req, res){
+    res.render('test.jade');
+});
+
+app.listen(3000);

examples/views/test.jade

@@ -0,0 +1,14 @@
+<h2>Original Image<h2>
+<img src="../image/?url=http%3A%2F%2Flocalhost%3A3000%2Fimages%2Ftest.jpg" />
+
+<h2>Resize<h2>
+<img src="../image/?url=http%3A%2F%2Flocalhost%3A3000%2Fimages%2Ftest.jpg&resize=1&height=120" />
+
+<h2>Grayscale<h2>
+<img src="../image/?url=http%3A%2F%2Flocalhost%3A3000%2Fimages%2Ftest.jpg&grayscale=1" />
+
+<h2>PNG Conversion<h2>
+<img src="../image/?url=http%3A%2F%2Flocalhost%3A3000%2Fimages%2Ftest.jpg&format=png" />
+
+<h2>Resize + Grayscale + GIF Conversion<h2>
+<img src="../image/?url=http%3A%2F%2Flocalhost%3A3000%2Fimages%2Ftest.jpg&format=gif&resize=1&height=210&grayscale=1" />

image-proxy.js

@@ -0,0 +1,103 @@
+var fs            = require('fs'),
+path              = require('path'),
+mime              = require('mime'),
+url               = require('url'),
+http              = require('http'),
+gm                = require('gm');
+
+var run = function(req, res){
+
+    var remoteUrl = decodeURI(req.param('url'));
+    var urlObject = url.parse(remoteUrl);
+    var options = urlObject;
+    var fileExt = path.extname(remoteUrl);
+    var urlHost = urlObject.hostname;
+
+    if(urlObject.port != undefined)
+         urlHost += ":"+urlObject.port;
+
+    if(urlHost != req.headers.host)
+        throw('Error: Only local proxy allowed.' +  urlHost + "  " + req.headers.host);
+
+    http.get(options, function(res) {
+
+        var localFile = getRandomFileName(fileExt);
+        var file = fs.createWriteStream(localFile);
+
+        res.on('data', function(data) {
+            file.write(data);
+        }).on('end', function() {
+
+            file.end();
+
+            if(!validateMime(localFile))
+                throw "Error: Unsupported file type.";
+
+            var outputImage = gm(localFile);
+
+            if(req.param('resize') == 1)
+            {
+                var newWidth = req.param('width');
+                var newHeight = req.param('height');
+
+                if(newHeight == null && newWidth == null)
+                    throw("Atleast one parameter from height or width should be defined.");
+                else
+                {
+                    outputImage = outputImage.resize(newWidth, newHeight);
+                }
+            }
+
+            if(req.param('grayscale') == 1)
+            {
+                outputImage = outputImage.type('grayscale');
+            }
+
+            if(req.param('format') != undefined)
+            {
+                outputImage = outputImage.setFormat(req.param('format'));
+                imageType = req.param('format');
+            }
+
+            fs.unlink(localFile, function (err) {
+              if (err) throw err;
+            });
+
+            outputImage.stream(renderImage);
+        });
+
+    }).on('error', function(e) {
+        throw('File cannot be downloaded: ' + e.message)
+    });
+
+    function renderImage(err, stdout, stderr) {
+
+        res.setHeader('Content-type', 'image/' + fileExt.substring(1));
+
+        stdout.on('data', function(chunk) {
+            res.write(chunk);
+        });
+        stdout.on('end', function() {
+            res.end();
+        });
+    }
+
+};
+
+function validateMime(name)
+{
+    var type = mime.lookup(name);
+    var validTypes = ['image/jpeg', 'image/png', 'image/gif', 'image/jpg'];
+
+    if(validTypes.indexOf(type) == -1)
+        return false;
+    else
+        return true;
+}
+
+function getRandomFileName(ext)
+{
+    return __dirname + "/temp/" + Math.floor(Math.random()*100000000) + ext;
+}
+
+exports.run = run;

package.json

@@ -0,0 +1,38 @@
+{
+  "name": "connect-image-proxy",
+  "version": "0.0.1",
+
+  "description": "Middleware for proxying and manipulating images.",
+  "keywords": ["images", "proxy", "graphicsmagick", "express", "middleware", "connect", "server-side"],
+
+  "homepage": "https://github.com/mysociety/node-connect-image-proxy",
+  "bugs": {
+    "url" : "https://github.com/mysociety/node-connect-image-proxy/issues"
+  },
+
+  "contributors": [
+    "Edmund von der Burg <evdb@mysociety.org> (http://www.mysociety.org/)",
+    "Chetan Bansal <chetan1@gmail.com>"
+  ],
+
+  "main": "connect-image-proxy",
+
+  "repository": {
+    "type": "git",
+    "url": "http://github.com/mysociety/node-connect-image-proxy.git"
+  },
+
+  "dependencies": {
+    "gm":      ">= 1.3.0",
+    "mime": "1.2.4"
+  },
+
+  "devDependencies": {
+     "express":  ">=2 <3",
+     "jade":  ">= 0.25.0"
+  },
+
+  "engines": {
+    "node": "*"
+  }
+}