Argument store added to updateEntityProperties.
This argument determines if an entity should be stored in the data model after its properties are updated.
It may be useful, for example, along with tasks (Task Queue API). One may want to make some modifications to an entity during execution of a task, but the developer is sure that at least one new task, which also wants to modify the entity, will be queued, so he or she can just update the entity without saving the changes to the data model, set the entity in memcache and the following task (which is to be executed very shortly) is to retrive the current entity from the memcache (without any expensive calls to the actual data model).
import os
import re
from webob import Request, Response
from webob import exc
from tempita import HTMLTemplate
VIEW_TEMPLATE = HTMLTemplate("""\
<html>
<head>
<title>{{page.title}}</title>
</head>
<body>
<h1>{{page.title}}</h1>
{{if message}}
<div style="background-color: #99f">{{message}}</div>
{{endif}}
<div>{{page.content|html}}</div>
<hr>
<a href="{{req.url}}?action=edit">Edit</a>
</body>
</html>
""")
EDIT_TEMPLATE = HTMLTemplate("""\
<html>
<head>
<title>Edit: {{page.title}}</title>
</head>
<body>
{{if page.exists}}
<h1>Edit: {{page.title}}</h1>
{{else}}
<h1>Create: {{page.title}}</h1>
{{endif}}
<form action="{{req.path_url}}" method="POST">
<input type="hidden" name="mtime" value="{{page.mtime}}">
Title: <input type="text" name="title" style="width: 70%" value="{{page.title}}"><br>
Content: <input type="submit" value="Save">
<a href="{{req.path_url}}">Cancel</a>
<br>
<textarea name="content" style="width: 100%; height: 75%" rows="40">{{page.content}}</textarea>
<br>
<input type="submit" value="Save">
<a href="{{req.path_url}}">Cancel</a>
</form>
</body></html>
""")
class WikiApp(object):
view_template = VIEW_TEMPLATE
edit_template = EDIT_TEMPLATE
def __init__(self, storage_dir):
self.storage_dir = os.path.abspath(os.path.normpath(storage_dir))
def __call__(self, environ, start_response):
req = Request(environ)
action = req.params.get('action', 'view')
page = self.get_page(req.path_info)
try:
try:
meth = getattr(self, 'action_%s_%s' % (action, req.method))
except AttributeError:
raise exc.HTTPBadRequest('No such action %r' % action).exception
resp = meth(req, page)
except exc.HTTPException, e:
resp = e
return resp(environ, start_response)
def get_page(self, path):
path = path.lstrip('/')
if not path:
path = 'index'
path = os.path.join(self.storage_dir)
path = os.path.normpath(path)
if path.endswith('/'):
path += 'index'
if not path.startswith(self.storage_dir):
raise exc.HTTPBadRequest("Bad path").exception
path += '.html'
return Page(path)
def action_view_GET(self, req, page):
if not page.exists:
return exc.HTTPTemporaryRedirect(
location=req.url + '?action=edit')
if req.cookies.get('message'):
message = req.cookies['message']
else:
message = None
text = self.view_template.substitute(
page=page, req=req, message=message)
resp = Response(text)
if message:
resp.delete_cookie('message')
else:
resp.last_modified = page.mtime
resp.conditional_response = True
return resp
def action_view_POST(self, req, page):
submit_mtime = int(req.params.get('mtime') or '0') or None
if page.mtime != submit_mtime:
return exc.HTTPPreconditionFailed(
"The page has been updated since you started editing it")
page.set(
title=req.params['title'],
content=req.params['content'])
resp = exc.HTTPSeeOther(
location=req.path_url)
resp.set_cookie('message', 'Page updated')
return resp
def action_edit_GET(self, req, page):
text = self.edit_template.substitute(
page=page, req=req)
return Response(text)
class Page(object):
def __init__(self, filename):
self.filename = filename
@property
def exists(self):
return os.path.exists(self.filename)
@property
def title(self):
if not self.exists:
# we need to guess the title
basename = os.path.splitext(os.path.basename(self.filename))[0]
basename = re.sub(r'[_-]', ' ', basename)
return basename.capitalize()
content = self.full_content
match = re.search(r'<title>(.*?)</title>', content, re.I|re.S)
return match.group(1)
@property
def full_content(self):
f = open(self.filename, 'rb')
try:
return f.read()
finally:
f.close()
@property
def content(self):
if not self.exists:
return ''
content = self.full_content
match = re.search(r'<body[^>]*>(.*?)</body>', content, re.I|re.S)
return match.group(1)
@property
def mtime(self):
if not self.exists:
return None
else:
return os.stat(self.filename).st_mtime
def set(self, title, content):
dir = os.path.dirname(self.filename)
if not os.path.exists(dir):
os.makedirs(dir)
new_content = """<html><head><title>%s</title></head><body>%s</body></html>""" % (
title, content)
f = open(self.filename, 'wb')
f.write(new_content)
f.close()
if __name__ == '__main__':
import optparse
parser = optparse.OptionParser(
usage='%prog --port=PORT'
)
parser.add_option(
'-p', '--port',
default='8080',
dest='port',
type='int',
help='Port to serve on (default 8080)')
parser.add_option(
'--wiki-data',
default='./wiki',
dest='wiki_data',
help='Place to put wiki data into (default ./wiki/)')
options, args = parser.parse_args()
print 'Writing wiki pages to %s' % options.wiki_data
app = WikiApp(options.wiki_data)
from wsgiref.simple_server import make_server
httpd = make_server('localhost', options.port, app)
print 'Serving on http://localhost:%s' % options.port
try:
httpd.serve_forever()
except KeyboardInterrupt:
print '^C'