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diff --git a/ipsilon/util/http.py b/ipsilon/util/http.py
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+++ b/ipsilon/util/http.py
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+# Copyright (C) 2015 Ipsilon project Contributors, for license see COPYING
+
+import cherrypy
+import fnmatch
+
+
+def require_content_type(required=None, absent_ok=True, debug=False):
+    '''CherryPy Tool that validates request Content-Type.
+
+    This is a CherryPy Tool that checks the Content-Type in a request and
+    raises HTTP Error 415 "Unsupported Media Type" if it does not match.
+
+    The tool accepts a glob style pattern or list of patterns (see fnmatch)
+    and verifies the Content-Type in the request matches at least one of
+    the patterns, if not a HTTP Error 415 "Unsupported Media Type" is raised.
+
+    If absent_ok is False and if the request does not contain a
+    Content-Type header a HTTP Error 415 "Unsupported Media Type" is
+    raised.
+
+    The tool may be deployed use any of the standard methods for
+    invoking CherryPy tools, for example as a decorator:
+
+    @cherrypy.tools.require_content_type(required='text/xml')
+    def POST(self, *args, **kwargs):
+        pass
+
+    :param required: May be a single string or a list of strings. Each
+           string is interpreted as a glob style pattern (see fnmatch).
+           The Content-Type must match at least one pattern.
+
+    :param absent_ok: Boolean specifying if the Content-Type header
+           must be present or if it is OK to be absent.
+
+    '''
+    if required is None:
+        return
+
+    if isinstance(required, basestring):
+        required = [required]
+
+    content_type = cherrypy.request.body.content_type.value
+    pattern = None
+    match = False
+    if content_type:
+        for pattern in required:
+            if fnmatch.fnmatch(content_type, pattern):
+                match = True
+                break
+    else:
+        if absent_ok:
+            return
+
+    if debug:
+        cherrypy.log('require_content_type: required=%s, absent_ok=%s '
+                     'content_type=%s match=%s pattern=%s' %
+                     required, absent_ok, content_type, match, pattern)
+
+    if not match:
+        acceptable = ', '.join(['"%s"' % x for x in required])
+        if content_type:
+            content_type = '"%s"' % content_type
+        else:
+            content_type = 'not specified'
+        message = ('Content-Type must match one of following patterns [%s], '
+                   'but the Content-Type was %s' %
+                   (acceptable, content_type))
+        raise cherrypy.HTTPError(415, message=message)