More refactoring - move various less core stuff into utils etc

4 files changed, 303 insertions, 0 deletions

diff --git a/djangorestframework/utils/__init__.py b/djangorestframework/utils/__init__.py
new file mode 100644
index 00000000..9dc769be
--- /dev/null
+++ b/djangorestframework/utils/__init__.py
@@ -0,0 +1,158 @@
+from django.utils.encoding import smart_unicode
+from django.utils.xmlutils import SimplerXMLGenerator
+from django.core.urlresolvers import resolve
+from django.conf import settings
+
+from djangorestframework.compat import StringIO
+
+import re
+import xml.etree.ElementTree as ET
+
+
+#def admin_media_prefix(request):
+#    """Adds the ADMIN_MEDIA_PREFIX to the request context."""
+#    return {'ADMIN_MEDIA_PREFIX': settings.ADMIN_MEDIA_PREFIX}
+
+MSIE_USER_AGENT_REGEX = re.compile(r'^Mozilla/[0-9]+\.[0-9]+ \([^)]*; MSIE [0-9]+\.[0-9]+[a-z]?;[^)]*\)(?!.* Opera )')
+
+def as_tuple(obj):
+    """Given obj return a tuple"""
+    if obj is None:
+        return ()
+    elif isinstance(obj, list):
+        return tuple(obj)
+    elif isinstance(obj, tuple):
+        return obj
+    return (obj,)
+
+  
+def url_resolves(url):
+    """Return True if the given URL is mapped to a view in the urlconf, False otherwise."""
+    try:
+        resolve(url)
+    except:
+        return False
+    return True
+
+
+# From http://www.koders.com/python/fidB6E125C586A6F49EAC38992CF3AFDAAE35651975.aspx?s=mdef:xml
+#class object_dict(dict):
+#    """object view of dict, you can 
+#    >>> a = object_dict()
+#    >>> a.fish = 'fish'
+#    >>> a['fish']
+#    'fish'
+#    >>> a['water'] = 'water'
+#    >>> a.water
+#    'water'
+#    >>> a.test = {'value': 1}
+#    >>> a.test2 = object_dict({'name': 'test2', 'value': 2})
+#    >>> a.test, a.test2.name, a.test2.value
+#    (1, 'test2', 2)
+#    """
+#    def __init__(self, initd=None):
+#        if initd is None:
+#            initd = {}
+#        dict.__init__(self, initd)
+#
+#    def __getattr__(self, item):
+#        d = self.__getitem__(item)
+#        # if value is the only key in object, you can omit it
+#        if isinstance(d, dict) and 'value' in d and len(d) == 1:
+#            return d['value']
+#        else:
+#            return d
+#
+#    def __setattr__(self, item, value):
+#        self.__setitem__(item, value)
+
+
+# From xml2dict
+class XML2Dict(object):
+
+    def __init__(self):
+        pass
+
+    def _parse_node(self, node):
+        node_tree = {}
+        # Save attrs and text, hope there will not be a child with same name
+        if node.text:
+            node_tree = node.text
+        for (k,v) in node.attrib.items():
+            k,v = self._namespace_split(k, v)
+            node_tree[k] = v
+        #Save childrens
+        for child in node.getchildren():
+            tag, tree = self._namespace_split(child.tag, self._parse_node(child))
+            if  tag not in node_tree: # the first time, so store it in dict
+                node_tree[tag] = tree
+                continue
+            old = node_tree[tag]
+            if not isinstance(old, list):
+                node_tree.pop(tag)
+                node_tree[tag] = [old] # multi times, so change old dict to a list       
+            node_tree[tag].append(tree) # add the new one      
+
+        return  node_tree
+
+
+    def _namespace_split(self, tag, value):
+        """
+           Split the tag  '{http://cs.sfsu.edu/csc867/myscheduler}patients'
+             ns = http://cs.sfsu.edu/csc867/myscheduler
+             name = patients
+        """
+        result = re.compile("\{(.*)\}(.*)").search(tag)
+        if result:
+            value.namespace, tag = result.groups()    
+        return (tag, value)
+
+    def parse(self, file):
+        """parse a xml file to a dict"""
+        f = open(file, 'r')
+        return self.fromstring(f.read()) 
+
+    def fromstring(self, s):
+        """parse a string"""
+        t = ET.fromstring(s)
+        unused_root_tag, root_tree = self._namespace_split(t.tag, self._parse_node(t))
+        return root_tree
+
+
+def xml2dict(input):
+    return XML2Dict().fromstring(input)
+
+
+# Piston:
+class XMLRenderer():
+    def _to_xml(self, xml, data):
+        if isinstance(data, (list, tuple)):
+            for item in data:
+                xml.startElement("list-item", {})
+                self._to_xml(xml, item)
+                xml.endElement("list-item")
+
+        elif isinstance(data, dict):
+            for key, value in data.iteritems():
+                xml.startElement(key, {})
+                self._to_xml(xml, value)
+                xml.endElement(key)
+
+        else:
+            xml.characters(smart_unicode(data))
+
+    def dict2xml(self, data):
+        stream = StringIO.StringIO() 
+
+        xml = SimplerXMLGenerator(stream, "utf-8")
+        xml.startDocument()
+        xml.startElement("root", {})
+
+        self._to_xml(xml, data)
+
+        xml.endElement("root")
+        xml.endDocument()
+        return stream.getvalue()
+
+def dict2xml(input):
+    return XMLRenderer().dict2xml(input)
diff --git a/djangorestframework/utils/breadcrumbs.py b/djangorestframework/utils/breadcrumbs.py
new file mode 100644
index 00000000..1e604efc
--- /dev/null
+++ b/djangorestframework/utils/breadcrumbs.py
@@ -0,0 +1,30 @@
+from django.core.urlresolvers import resolve
+from djangorestframework.utils.description import get_name
+
+def get_breadcrumbs(url):
+    """Given a url returns a list of breadcrumbs, which are each a tuple of (name, url)."""
+    
+    def breadcrumbs_recursive(url, breadcrumbs_list):
+        """Add tuples of (name, url) to the breadcrumbs list, progressively chomping off parts of the url."""
+        
+        try:
+            (view, unused_args, unused_kwargs) = resolve(url)
+        except:
+            pass
+        else:
+            if callable(view):
+                breadcrumbs_list.insert(0, (get_name(view), url))
+        
+        if url == '':
+            # All done
+            return breadcrumbs_list
+    
+        elif url.endswith('/'):
+            # Drop trailing slash off the end and continue to try to resolve more breadcrumbs
+            return breadcrumbs_recursive(url.rstrip('/'), breadcrumbs_list)
+    
+        # Drop trailing non-slash off the end and continue to try to resolve more breadcrumbs
+        return breadcrumbs_recursive(url[:url.rfind('/') + 1], breadcrumbs_list)
+
+    return breadcrumbs_recursive(url, [])
+
diff --git a/djangorestframework/utils/description.py b/djangorestframework/utils/description.py
new file mode 100644
index 00000000..f7145c0f
--- /dev/null
+++ b/djangorestframework/utils/description.py
@@ -0,0 +1,37 @@
+"""Get a descriptive name and description for a view,
+based on class name and docstring, and override-able by 'name' and 'description' attributes"""
+import re
+
+def get_name(view):
+    """Return a name for the view.
+    
+    If view has a name attribute, use that, otherwise use the view's class name, with 'CamelCaseNames' converted to 'Camel Case Names'."""
+    if getattr(view, 'name', None) is not None:
+        return view.name
+
+    if getattr(view, '__name__', None) is not None:
+        name = view.__name__
+    elif getattr(view, '__class__', None) is not None:  # TODO: should be able to get rid of this case once refactoring to 1.3 class views is complete
+        name = view.__class__.__name__
+    else:
+        return ''
+
+    return re.sub('(((?<=[a-z])[A-Z])|([A-Z](?![A-Z]|$)))', ' \\1', name).strip()
+
+def get_description(view):
+    """Provide a description for the view.
+
+    By default this is the view's docstring with nice unindention applied."""
+    if getattr(view, 'description', None) is not None:
+        return getattr(view, 'description')
+
+    if getattr(view, '__doc__', None) is not None:
+        whitespace_counts = [len(line) - len(line.lstrip(' ')) for line in view.__doc__.splitlines()[1:] if line.lstrip()]
+
+        if whitespace_counts:
+            whitespace_pattern = '^' + (' ' * min(whitespace_counts))
+            return re.sub(re.compile(whitespace_pattern, re.MULTILINE), '', view.__doc__)
+
+        return view.__doc__
+    
+    return ''
\ No newline at end of file
diff --git a/djangorestframework/utils/mediatypes.py b/djangorestframework/utils/mediatypes.py
new file mode 100644
index 00000000..92d9264c
--- /dev/null
+++ b/djangorestframework/utils/mediatypes.py
@@ -0,0 +1,78 @@
+"""
+Handling of media types, as found in HTTP Content-Type and Accept headers.
+
+See http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.7
+"""
+
+from django.http.multipartparser import parse_header
+
+
+class MediaType(object):
+    def __init__(self, media_type_str):
+        self.orig = media_type_str
+        self.media_type, self.params = parse_header(media_type_str)
+        self.main_type, sep, self.sub_type = self.media_type.partition('/')
+
+    def match(self, other):
+        """Return true if this MediaType satisfies the constraint of the given MediaType."""
+        for key in other.params.keys():
+            if key != 'q' and other.params[key] != self.params.get(key, None):
+                return False
+
+        if other.sub_type != '*' and other.sub_type != self.sub_type:
+            return False
+
+        if other.main_type != '*' and other.main_type != self.main_type:
+            return False
+
+        return True
+
+    def precedence(self):
+        """
+        Return a precedence level for the media type given how specific it is.
+        """
+        if self.main_type == '*':
+            return 1
+        elif self.sub_type == '*':
+            return 2
+        elif not self.params or self.params.keys() == ['q']:
+            return 3
+        return 4
+
+    def quality(self):
+        """
+        Return a quality level for the media type.
+        """
+        try:
+            return Decimal(self.params.get('q', '1.0'))
+        except:
+            return Decimal(0)
+    
+    def score(self):
+        """
+        Return an overall score for a given media type given it's quality and precedence.
+        """
+        # NB. quality values should only have up to 3 decimal points
+        # http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.9
+        return self.quality * 10000 + self.precedence
+
+    def is_form(self):
+        """
+        Return True if the MediaType is a valid form media type as defined by the HTML4 spec.
+        (NB. HTML5 also adds text/plain to the list of valid form media types, but we don't support this here)
+        """
+        return self.media_type == 'application/x-www-form-urlencoded' or \
+               self.media_type == 'multipart/form-data'
+    
+    def as_tuple(self):
+        return (self.main_type, self.sub_type, self.params)
+
+    def __repr__(self):
+        return "<MediaType %s>" % (self.as_tuple(),)
+
+    def __str__(self):
+        return unicode(self).encode('utf-8')
+
+    def __unicode__(self):
+        return self.orig
+