Mercurial > hg > commentator
annotate commentator/middleware.py @ 5:451169e51935
work to make cache expiry work
| author | k0s <k0scist@gmail.com> |
|---|---|
| date | Fri, 26 Feb 2010 12:27:25 -0500 |
| parents | d0d8524d9495 |
| children |
| rev | line source |
|---|---|
| 0 | 1 """ |
| 2 request dispatcher: | |
| 3 data persisting across requests should go here | |
| 4 """ | |
| 5 | |
| 6 import os | |
| 7 import re | |
| 5 | 8 import time |
| 0 | 9 |
| 10 from handlers import PostComment | |
|
2
689b9d928dc8
add date, reflect api change of lxmlmiddleware
k0s <k0scist@gmail.com>
parents:
0
diff
changeset
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11 #from model import CouchComments |
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689b9d928dc8
add date, reflect api change of lxmlmiddleware
k0s <k0scist@gmail.com>
parents:
0
diff
changeset
|
12 from model import PickleComments |
| 0 | 13 from genshi.template import TemplateLoader |
| 14 from lxml import etree | |
| 15 from lxmlmiddleware import LXMLMiddleware | |
| 16 from paste.fileapp import FileApp | |
| 17 from pkg_resources import resource_filename | |
| 18 from string import Template | |
| 19 from webob import Request, Response, exc | |
| 20 | |
| 21 class LaxTemplate(Template): | |
| 22 idpattern = r'[_a-z0-9]+' | |
| 23 | |
| 24 class Commentator(LXMLMiddleware): | |
| 25 | |
| 26 ### class level variables | |
| 27 defaults = { 'auto_reload': 'False', | |
| 28 'database': 'commentator', | |
|
2
689b9d928dc8
add date, reflect api change of lxmlmiddleware
k0s <k0scist@gmail.com>
parents:
0
diff
changeset
|
29 'date_format': '%H:%M %m/%d/%Y', |
| 0 | 30 'template_dirs': '', |
| 31 'pattern': '.*', | |
| 32 'path': 'html', | |
| 33 'url': '.comment', | |
| 34 'template': 'comment.html' } | |
| 35 | |
| 36 def __init__(self, app, **kw): | |
| 37 | |
| 38 self.app = app | |
| 39 | |
| 40 # set instance parameters from kw and defaults | |
| 41 for key in self.defaults: | |
| 42 setattr(self, key, kw.get(key, self.defaults[key])) | |
| 43 self.auto_reload = self.auto_reload.lower() == 'true' | |
| 44 | |
| 45 # request handlers | |
| 46 self.handlers = [ PostComment ] | |
| 47 | |
| 48 # template loader | |
| 49 self.template_dirs = self.template_dirs.split() | |
| 50 self.template_dirs.append(resource_filename(__name__, 'templates')) | |
| 51 self.loader = TemplateLoader(self.template_dirs, | |
| 52 auto_reload=self.auto_reload) | |
| 53 | |
| 54 # URL,path | |
| 55 assert '#' in self.pattern | |
| 56 self.url_pattern, self.xpath_pattern = self.pattern.split('#', 1) | |
| 57 assert '->' in self.xpath_pattern | |
| 58 self.xpath_pattern, self.mapping = [i.strip() for i in self.xpath_pattern.split('->')] | |
| 59 | |
| 60 # string template for URL substitution | |
| 61 self.mapping = LaxTemplate(self.mapping) | |
| 62 | |
| 63 # backend: comment storage | |
| 64 self.model = PickleComments(self.database) | |
| 65 | |
| 66 def __call__(self, environ, start_response): | |
| 67 | |
| 68 # get a request object | |
| 69 request = Request(environ) | |
| 70 | |
| 71 # get the path | |
| 72 path = request.path_info.strip('/').split('/') | |
| 73 if path == ['']: | |
| 74 path = [] | |
| 75 request.environ['path'] = path | |
| 76 | |
| 5 | 77 # XXX save the path; not sure why i need to do this |
| 0 | 78 environ['commentator.path_info'] = request.path_info |
| 79 | |
| 80 # match the request to a handler | |
| 81 for h in self.handlers: | |
| 82 handler = h.match(self, request) | |
| 83 if handler is not None: | |
| 84 break | |
| 85 else: | |
| 86 return LXMLMiddleware.__call__(self, environ, start_response) | |
| 87 | |
| 88 # get response | |
| 89 res = handler() | |
| 90 return res(environ, start_response) | |
| 91 | |
|
2
689b9d928dc8
add date, reflect api change of lxmlmiddleware
k0s <k0scist@gmail.com>
parents:
0
diff
changeset
|
92 def manipulate(self, request, response, tree): |
|
689b9d928dc8
add date, reflect api change of lxmlmiddleware
k0s <k0scist@gmail.com>
parents:
0
diff
changeset
|
93 url_match = re.match(self.url_pattern, request.environ['commentator.path_info']) |
| 0 | 94 if not url_match: |
| 95 return tree | |
| 96 | |
| 97 # make string template of the groups | |
| 98 groups_dict = dict([(str(index+1), value) | |
| 99 for index, value in enumerate(url_match.groups())]) | |
| 100 | |
|
3
d0d8524d9495
finish basic API...still doesnt expire results correctly
k0s <k0scist@gmail.com>
parents:
2
diff
changeset
|
101 last_modified = None |
| 5 | 102 commentable = False |
| 0 | 103 for element in tree.findall(self.xpath_pattern): |
| 5 | 104 commentable = True |
| 0 | 105 |
| 106 # get url | |
| 107 str_dict = groups_dict.copy() | |
| 108 for key in element.keys(): | |
| 109 str_dict[key] = element.get(key) | |
| 110 uri = self.mapping.substitute(str_dict) | |
| 111 | |
| 112 # genshi data | |
| 113 data = {} | |
| 114 data['comments'] = self.model.comments(uri) | |
|
3
d0d8524d9495
finish basic API...still doesnt expire results correctly
k0s <k0scist@gmail.com>
parents:
2
diff
changeset
|
115 if data['comments']: |
| 5 | 116 _last_modified = data['comments'][-1]['date'] |
| 117 if last_modified is None: | |
| 118 last_modified = _last_modified | |
| 119 else: | |
| 120 last_modified = max(last_modified, _last_modified) | |
| 0 | 121 data['action'] = '%s/%s' % (uri, self.url) |
|
2
689b9d928dc8
add date, reflect api change of lxmlmiddleware
k0s <k0scist@gmail.com>
parents:
0
diff
changeset
|
122 data['date_format'] = self.date_format |
|
689b9d928dc8
add date, reflect api change of lxmlmiddleware
k0s <k0scist@gmail.com>
parents:
0
diff
changeset
|
123 data['request'] = request |
| 0 | 124 |
| 125 # render template | |
| 126 template = self.loader.load(self.template) | |
| 127 comments = template.generate(**data).render() | |
| 128 comments = etree.fromstring(comments) | |
| 129 element.append(comments) | |
| 130 | |
| 5 | 131 if commentable: |
| 132 response.cache_expires(0) | |
| 133 | |
| 134 if last_modified: # there are comments | |
| 135 page_age = time.mktime(response.last_modified.timetuple()) | |
| 136 comments_age = time.mktime(last_modified.timetuple()) | |
| 137 if comments_age > page_age: | |
| 138 response.last_modified = comments_age | |
| 139 | |
| 0 | 140 return tree |