Initial import

ebook_converter/utils/resources.py

@@ -0,0 +1,106 @@
+#!/usr/bin/env python2
+# vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
+
+__license__   = 'GPL v3'
+__copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'
+__docformat__ = 'restructuredtext en'
+
+
+import sys, os
+
+from calibre import config_dir
+from polyglot.builtins import builtins
+
+
+user_dir = os.path.join(config_dir, 'resources')
+
+
+class PathResolver(object):
+
+    def __init__(self):
+        self.locations = [sys.resources_location]
+        self.cache = {}
+
+        def suitable(path):
+            try:
+                return os.path.exists(path) and os.path.isdir(path) and \
+                       os.listdir(path)
+            except:
+                pass
+            return False
+
+        self.default_path = sys.resources_location
+
+        dev_path = os.environ.get('CALIBRE_DEVELOP_FROM', None)
+        self.using_develop_from = False
+        if dev_path is not None:
+            dev_path = os.path.join(os.path.abspath(
+                os.path.dirname(dev_path)), 'resources')
+            if suitable(dev_path):
+                self.locations.insert(0, dev_path)
+                self.default_path = dev_path
+                self.using_develop_from = True
+
+        self.user_path = None
+        if suitable(user_dir):
+            self.locations.insert(0, user_dir)
+            self.user_path = user_dir
+
+    def __call__(self, path, allow_user_override=True):
+        path = path.replace(os.sep, '/')
+        key = (path, allow_user_override)
+        ans = self.cache.get(key, None)
+        if ans is None:
+            for base in self.locations:
+                if not allow_user_override and base == self.user_path:
+                    continue
+                fpath = os.path.join(base, *path.split('/'))
+                if os.path.exists(fpath):
+                    ans = fpath
+                    break
+
+            if ans is None:
+                ans = os.path.join(self.default_path, *path.split('/'))
+
+            self.cache[key] = ans
+
+        return ans
+
+    def set_data(self, path, data=None):
+        self.cache.pop((path, True), None)
+        fpath = os.path.join(user_dir, *path.split('/'))
+        if data is None:
+            if os.path.exists(fpath):
+                os.remove(fpath)
+        else:
+            base = os.path.dirname(fpath)
+            if not os.path.exists(base):
+                os.makedirs(base)
+            with open(fpath, 'wb') as f:
+                f.write(data)
+
+
+_resolver = PathResolver()
+
+
+def get_path(path, data=False, allow_user_override=True):
+    fpath = _resolver(path, allow_user_override=allow_user_override)
+    if data:
+        with open(fpath, 'rb') as f:
+            return f.read()
+    return fpath
+
+
+def get_image_path(path, data=False, allow_user_override=True):
+    if not path:
+        return get_path('images', allow_user_override=allow_user_override)
+    return get_path('images/'+path, data=data, allow_user_override=allow_user_override)
+
+
+def set_data(path, data=None):
+    return _resolver.set_data(path, data)
+
+
+builtins.__dict__['P'] = get_path
+builtins.__dict__['I'] = get_image_path