image-checker.py: Fix python 3 compatibility (#105)

Move from using wget library to direct calls to urllib, doesn't add too
much additional complexity to the code. Also handle HTTP errors as
script errors instead of terminating abnormally.

Fixes #104

test/image-checker.py

@@ -10,11 +10,21 @@
 import os
 import re
 import sys
-import tempfile
-import wget  # pip install wget
 import yaml  # pip install pyyaml
+import io
+
+if sys.version_info >= (3, 0):
+    from urllib.error import URLError
+    from urllib.request import Request, urlopen
+else:
+    from urllib2 import URLError, Request, urlopen
 
 DISALLOWED_CHARS_REGEX = re.compile('[^a-z0-9_-]')
+HEADERS = {
+    "User-Agent":
+        "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) "
+        "Chrome/35.0.1916.153 Safari/537.36 SE 2.X MetaSr 1.0"
+}
 
 
 def load_yaml(filename):
@@ -84,11 +94,6 @@ def check_yaml(yaml_filename, resize=False):
     out = "Checking {}".format(yaml_filename)
     sys.stdout.write(out)
 
-    # monkey patch
-    wget.ulib.URLopener.version = (
-        "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) "
-        "Chrome/35.0.1916.153 Safari/537.36 SE 2.X MetaSr 1.0")
-
     data = load_yaml(yaml_filename)
 
     urls_checked = set()
@@ -103,43 +108,46 @@ def check_yaml(yaml_filename, resize=False):
             urls_checked.add(url)
 
             sys.stdout.write('.')
-            download = wget.download(url, tempfile.gettempdir(), bar=None)
 
-            # Square images work best. Image can't be larger than 128px in
-            # width or height, and must be smaller than 64K in file size.
+            try:
+                download = urlopen(Request(url=url, headers=HEADERS))
+                body = download.read()
+                download.close()
 
-            if os.path.getsize(download) > 65536:
-                error = ("Error: must be smaller than 64K in file size: "
-                         "{}").format(url)
-                errors.append(error)
+                # Square images work best. Image can't be larger than 128px in
+                # width or height, and must be smaller than 64K in file size.
+                if len(body) > 65536:
+                    error = ("Error: must be smaller than 64K in file size: "
+                             "{}").format(url)
+                    errors.append(error)
 
-            with open(download, "rb") as f:
-                try:
+                with io.BytesIO(body) as f:
                     # Is it an image?
                     im = Image.open(f)
                     if im.width > 128 or im.height > 128:
-
                         if resize:
                             outfile = resize_image(im, yaml_filename, url)
                             message = "Info: resized {} to {}".format(
-                                    url, outfile)
+                                url, outfile)
                             resized.append(message)
 
                         error = ("Error: image can't be larger than 128px "
                                  "in width or height: {} {}".format(
-                                    im.size, url))
+                                     im.size, url))
                         errors.append(error)
 
                     elif im.width != im.height:
                         warning = ("Warning: square images work best: "
                                    "{} {}".format(im.size, url))
                         warnings.append(warning)
-                except IOError:
-                    error = "Error: cannot open as image: {}".format(url)
-                    errors.append(error)
-                    f.close()
-
-            os.remove(download)
+            except URLError as e:
+                error = "Error: cannot fetch image: {} ({})".format(url,
+                                                                    e.reason)
+                errors.append(error)
+            except IOError as e:
+                error = "Error: cannot open as image: {}: {}".format(url,
+                                                                     e.strerror)
+                errors.append(error)
 
     print()
     print()

test/requirements.txt

@@ -1,3 +1,2 @@
 pillow
 pyyaml
-wget