Update with querystring modifier support

This is related to tripviss#22

app.js

@@ -55,6 +55,7 @@ app.use((err, req, res, next) => {
   res.status(err.status || 500);
   res.json({
     error: err.message,
+    stack: err.stack,
   });
 });
 

src/image.js

@@ -36,7 +36,7 @@ function Image(request) {
   this.parseImage(request);
 
   // determine the requested modifications
-  this.modifiers = modifiers.parse(request.path);
+  this.modifiers = modifiers.parse(request.path, null, null, request.query);
 
   // pull the various parts needed from the request params
   this.parseUrl(request);
@@ -61,8 +61,8 @@ Image.validOutputFormats = ['jpeg', 'png', 'webp'];
 Image.prototype.parseImage = function(request){
   const parts = request.path.split('/');
   this.image = _.last(parts);
-  this.format = request.query.format;
-  this.outputFormat = request.query.outputFormat;
+  this.format = request.query.format || '';
+  this.outputFormat = request.query.outputFormat || '';
 };
 
 // Determine the file path for the requested image

src/lib/modifiers.js

@@ -287,9 +287,9 @@ var limitMaxDimension = function(mods, env){
 // Exposed method to parse an incoming URL for modifiers, can add a map of
 // named (preset) modifiers if need be (mostly just for unit testing). Named
 // modifiers are usually added via config json file in root of application.
-exports.parse = function(requestUrl, namedMods, envOverride){
+exports.parse = function(requestUrl, namedMods, envOverride, query) {
   // override 'env' for testing
-  if(typeof envOverride !== 'undefined'){
+  if(envOverride != null) {
     env = _.clone(envOverride);
   } else {
     env = _.clone(environment);
@@ -308,12 +308,12 @@ exports.parse = function(requestUrl, namedMods, envOverride){
 
   // set the mod keys and defaults
   mods = {
-    action: 'original',
-    height: null,
-    width: null,
-    gravity: gravity.default,
-    crop: crop.default,
-    quality: quality.default,
+    action: query.action || 'original',
+    height: !isNaN(+query.height) ? +query.height : null,
+    width: !isNaN(+query.width) ? +query.width : null,
+    gravity: query.gravity || gravity.default,
+    crop: query.crop || crop.default,
+    quality: query.quality || quality.default,
     hasModStr: false
   };