Added StandardCacheManagers product to trunk.

AcceleratedHTTPCacheManager.py

@@ -0,0 +1,306 @@
+##############################################################################
+# 
+# Zope Public License (ZPL) Version 1.0
+# -------------------------------------
+# 
+# Copyright (c) Digital Creations.  All rights reserved.
+# 
+# This license has been certified as Open Source(tm).
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+# 
+# 1. Redistributions in source code must retain the above copyright
+#    notice, this list of conditions, and the following disclaimer.
+# 
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions, and the following disclaimer in
+#    the documentation and/or other materials provided with the
+#    distribution.
+# 
+# 3. Digital Creations requests that attribution be given to Zope
+#    in any manner possible. Zope includes a "Powered by Zope"
+#    button that is installed by default. While it is not a license
+#    violation to remove this button, it is requested that the
+#    attribution remain. A significant investment has been put
+#    into Zope, and this effort will continue if the Zope community
+#    continues to grow. This is one way to assure that growth.
+# 
+# 4. All advertising materials and documentation mentioning
+#    features derived from or use of this software must display
+#    the following acknowledgement:
+# 
+#      "This product includes software developed by Digital Creations
+#      for use in the Z Object Publishing Environment
+#      (http://www.zope.org/)."
+# 
+#    In the event that the product being advertised includes an
+#    intact Zope distribution (with copyright and license included)
+#    then this clause is waived.
+# 
+# 5. Names associated with Zope or Digital Creations must not be used to
+#    endorse or promote products derived from this software without
+#    prior written permission from Digital Creations.
+# 
+# 6. Modified redistributions of any form whatsoever must retain
+#    the following acknowledgment:
+# 
+#      "This product includes software developed by Digital Creations
+#      for use in the Z Object Publishing Environment
+#      (http://www.zope.org/)."
+# 
+#    Intact (re-)distributions of any official Zope release do not
+#    require an external acknowledgement.
+# 
+# 7. Modifications are encouraged but must be packaged separately as
+#    patches to official Zope releases.  Distributions that do not
+#    clearly separate the patches from the original work must be clearly
+#    labeled as unofficial distributions.  Modifications which do not
+#    carry the name Zope may be packaged in any form, as long as they
+#    conform to all of the clauses above.
+# 
+# 
+# Disclaimer
+# 
+#   THIS SOFTWARE IS PROVIDED BY DIGITAL CREATIONS ``AS IS'' AND ANY
+#   EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+#   PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL DIGITAL CREATIONS OR ITS
+#   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+#   USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+#   ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+#   OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+#   OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+#   SUCH DAMAGE.
+# 
+# 
+# This software consists of contributions made by Digital Creations and
+# many individuals on behalf of Digital Creations.  Specific
+# attributions are listed in the accompanying credits file.
+# 
+##############################################################################
+'''
+Accelerated HTTP cache manager --
+  Adds caching headers to the response so that downstream caches will
+  cache according to a common policy.
+
+$Id$
+'''
+
+from OFS.Cache import Cache, CacheManager
+from OFS.SimpleItem import SimpleItem
+import time
+import Globals
+from Globals import HTMLFile
+import urlparse, httplib
+from urllib import quote
+from string import lower, join, split
+
+
+def http_date(value, format='%a, %d %b %Y %H:%M:%S GMT'):
+    return time.strftime(format, time.gmtime(value))
+
+
+class AcceleratedHTTPCache (Cache):
+    # Note the need to take thread safety into account.
+    # Also note that objects of this class are not persistent,
+    # nor do they use acquisition.
+    def __init__(self):
+        self.hit_counts = {}
+
+    def initSettings(self, kw):
+        # Note that we lazily allow AcceleratedHTTPCacheManager
+        # to verify the correctness of the internal settings.
+        self.__dict__.update(kw)
+
+    def ZCache_invalidate(self, ob):
+        # Note that this only works for default views of objects.
+        phys_path = os.getPhysicalPath()
+        if self.hit_counts.has_key(phys_path):
+            del self.hit_counts[phys_path]
+        ob_path = quote(join(phys_path, '/'))
+        results = []
+        for url in self.notify_urls:
+            if not url:
+                continue
+            # Send the PURGE request to each HTTP accelerator.
+            if lower(url[:7]) == 'http://':
+                u = url
+            else:
+                u = 'http://' + url
+            (scheme, host, path, params, query, fragment
+             ) = urlparse.urlparse(u)
+            if path[-1:] == '/':
+                p = path[:-1] + ob_path
+            else:
+                p = path + ob_path
+            h = httplib.HTTP(host)
+            h.putrequest('PURGE', p)
+            h.endheaders()
+            errcode, errmsg, headers = h.getreply()
+            h.getfile().read()  # Mandatory for httplib?
+            results.append('%s %s' % (errcode, errmsg))
+        return 'Server response(s): ' + join(results, ';')
+
+    def ZCache_get(self, ob, view_name, keywords, mtime_func, default):
+        return default
+
+    def ZCache_set(self, ob, data, view_name, keywords, mtime_func):
+        # Note the blatant ignorance of view_name, keywords, and
+        # mtime_func.  Standard HTTP accelerators are not able to make
+        # use of this data.
+        REQUEST = ob.REQUEST
+        RESPONSE = REQUEST.RESPONSE
+        anon = 1
+        u = REQUEST.get('AUTHENTICATED_USER', None)
+        if u is not None:
+            if u.getUserName() != 'Anonymous User':
+                anon = 0
+        phys_path = ob.getPhysicalPath()
+        if self.hit_counts.has_key(phys_path):
+            hits = self.hit_counts[phys_path]
+        else:
+            self.hit_counts[phys_path] = hits = [0,0]
+        if anon:
+            hits[0] = hits[0] + 1
+        else:
+            hits[1] = hits[1] + 1
+
+        if not anon and self.anonymous_only:
+            return
+        # Set HTTP Expires and Cache-Control headers
+        seconds=self.interval
+        expires=http_date(time.time() + seconds)
+        # RESPONSE.setHeader('Last-Modified', http_date(time.time()))
+        RESPONSE.setHeader('Cache-Control', 'max-age=%d' % seconds)
+        RESPONSE.setHeader('Expires', expires)
+
+
+caches = {}
+PRODUCT_DIR = split(__name__, '.')[-2]
+
+class AcceleratedHTTPCacheManager (CacheManager, SimpleItem):
+    ' '
+
+    __ac_permissions__ = (
+        ('View management screens', ('getSettings',
+                                     'manage_main',
+                                     'manage_stats',
+                                     'getCacheReport',
+                                     'sort_link')),
+        ('Change cache managers', ('manage_editProps',), ('Manager',)),
+        )
+
+    manage_options = (
+        {'label':'Properties', 'action':'manage_main',
+         'help':(PRODUCT_DIR, 'Accel.stx'),},
+        {'label':'Statistics', 'action':'manage_stats',
+         'help':(PRODUCT_DIR, 'Accel.stx'),},
+        ) + CacheManager.manage_options + SimpleItem.manage_options
+
+    meta_type = 'Accelerated HTTP Cache Manager'
+
+    def __init__(self, ob_id):
+        self.id = ob_id
+        self.title = ''
+        self._settings = {'anonymous_only':1,
+                          'interval':3600,
+                          'notify_urls':()}
+        self.__cacheid = '%s_%f' % (id(self), time.time())
+
+    def getId(self):
+        ' '
+        return self.id
+
+    ZCacheManager_getCache__roles__ = ()
+    def ZCacheManager_getCache(self):
+        cacheid = self.__cacheid
+        try:
+            return caches[cacheid]
+        except KeyError:
+            cache = AcceleratedHTTPCache()
+            cache.initSettings(self._settings)
+            caches[cacheid] = cache
+            return cache
+
+    def getSettings(self):
+        ' '
+        return self._settings.copy()  # Don't let DTML modify it.
+
+    manage_main = HTMLFile('propsAccel', globals())
+
+    def manage_editProps(self, title, settings=None, REQUEST=None):
+        ' '
+        if settings is None:
+            settings = REQUEST
+        self.title = str(title)
+        self._settings = {
+            'anonymous_only':settings['anonymous_only'] and 1 or 0,
+            'interval':int(settings['interval']),
+            'notify_urls':tuple(settings['notify_urls']),}
+        cache = self.ZCacheManager_getCache()
+        cache.initSettings(self._settings)
+        if REQUEST is not None:
+            return self.manage_main(
+                self, REQUEST, manage_tabs_message='Properties changed.')
+
+    manage_stats = HTMLFile('statsAccel', globals())
+
+    def _getSortInfo(self):
+        """
+        Returns the value of sort_by and sort_reverse.
+        If not found, returns default values.
+        """
+        req = self.REQUEST
+        sort_by = req.get('sort_by', 'anon')
+        sort_reverse = int(req.get('sort_reverse', 1))
+        return sort_by, sort_reverse        
+
+    def getCacheReport(self):
+        """
+        Returns the list of objects in the cache, sorted according to
+        the user's preferences.
+        """
+        sort_by, sort_reverse = self._getSortInfo()
+        c = self.ZCacheManager_getCache()
+        rval = []
+        for path, (anon, auth) in c.hit_counts.items():
+            rval.append({'path': join(path, '/'),
+                         'anon': anon,
+                         'auth': auth})
+        if sort_by:
+            rval.sort(lambda e1, e2, sort_by=sort_by:
+                      cmp(e1[sort_by], e2[sort_by]))
+            if sort_reverse:
+                rval.reverse()
+        return rval
+
+    def sort_link(self, name, id):
+        """
+        Utility for generating a sort link.
+        """
+        # XXX This ought to be in a library or something.
+        sort_by, sort_reverse = self._getSortInfo()
+        url = self.absolute_url() + '/manage_stats?sort_by=' + id
+        newsr = 0
+        if sort_by == id:
+            newsr = not sort_reverse
+        url = url + '&sort_reverse=' + (newsr and '1' or '0')
+        return '<a href="%s">%s</a>' % (url, name)
+
+
+Globals.default__class_init__(AcceleratedHTTPCacheManager)
+
+
+manage_addAcceleratedHTTPCacheManagerForm = HTMLFile('addAccel', globals())
+
+def manage_addAcceleratedHTTPCacheManager(self, id, REQUEST=None):
+    ' '
+    self._setObject(id, AcceleratedHTTPCacheManager(id))
+    if REQUEST is not None:
+        return self.manage_main(self, REQUEST)
+
+# FYI good resource: http://www.web-caching.com/proxy-caches.html