No Upscale filter

.gitignore

@@ -29,3 +29,5 @@ opencv
 /debian/thumbor.prerm.debhelper
 /debian/thumbor.substvars
 /debian/tmp/
+.ropeproject/
+.venv

thumbor/config.py

@@ -211,6 +211,7 @@
         'thumbor.filters.convolution',
         'thumbor.filters.blur',
         'thumbor.filters.extract_focal',
+        'thumbor.filters.no_upscale',
     ],
     'List of filters that thumbor will allow to be used in generated images. All of them must be ' +
     'full names of python modules (python must be able to import it)', 'Filters')

thumbor/filters/__init__.py

@@ -14,6 +14,7 @@
 STRIP_QUOTE = re.compile(r"^'(.+)'$")
 PHASE_POST_TRANSFORM = 'post_transform'
 PHASE_PRE_LOAD = 'pre-load'
+PHASE_AFTER_LOAD = 'after-load'
 
 
 def filter_method(*args, **kwargs):

thumbor/filters/no_upscale.py

@@ -0,0 +1,25 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# thumbor imaging service
+# https://github.com/globocom/thumbor/wiki
+
+# Licensed under the MIT license:
+# http://www.opensource.org/licenses/mit-license
+# Copyright (c) 2011 globo.com timehome@corp.globo.com
+
+
+import thumbor.filters
+from thumbor.filters import BaseFilter, filter_method
+
+
+class Filter(BaseFilter):
+    phase = thumbor.filters.PHASE_AFTER_LOAD
+
+    @filter_method()
+    def no_upscale(self):
+        image_size = self.engine.size
+        if self.context.request.width > image_size[0]:
+            self.context.request.width = image_size[0]
+        if self.context.request.height > image_size[1]:
+            self.context.request.height = image_size[1]

thumbor/handlers/__init__.py

@@ -87,13 +87,16 @@ def callback(normalized, buffer=None, engine=None):
                 engine = self.context.request.engine
                 engine.load(buffer, req.extension)
 
-            self.normalize_crops(normalized, req, engine)
+            def transform():
+                self.normalize_crops(normalized, req, engine)
 
-            if req.meta:
-                self.context.request.engine = JSONEngine(engine, req.image_url, req.meta_callback)
+                if req.meta:
+                    self.context.request.engine = JSONEngine(engine, req.image_url, req.meta_callback)
 
-            after_transform_cb = functools.partial(self.after_transform, self.context)
-            Transformer(self.context).transform(after_transform_cb)
+                after_transform_cb = functools.partial(self.after_transform, self.context)
+                Transformer(self.context).transform(after_transform_cb)
+
+            self.filters_runner.apply_filters(thumbor.filters.PHASE_AFTER_LOAD, transform)
 
         self._fetch(self.context.request.image_url, self.context.request.extension, callback)
 

thumbor/thumbor.conf

@@ -168,6 +168,7 @@ ALLOW_UNSAFE_URL = True
     #'thumbor.filters.rotate',
     #'thumbor.filters.format',
     #'thumbor.filters.max_bytes',
+    #'thumbor.filters.no_upscale',
 
     ## can only be applied if there are already points for the image being served
     ## this means that either you are using the local face detector or the image