Mercurial > p > roundup > code
view roundup/cgi/TAL/XMLParser.py @ 5710:0b79bfcb3312
Add support for making an idempotent POST. This allows retrying a POST
that was interrupted. It involves creating a post once only (poe) url
/rest/data/<class>/@poe/<random_token>. This url acts the same as a
post to /rest/data/<class>. However once the @poe url is used, it
can't be used for a second POST.
To make these changes:
1) Take the body of post_collection into a new post_collection_inner
function. Have post_collection call post_collection_inner.
2) Add a handler for POST to rest/data/class/@poe. This will return a
unique POE url. By default the url expires after 30 minutes. The
POE random token is only good for a specific user and is stored in
the session db.
3) Add a handler for POST to rest/data/<class>/@poe/<random token>.
The random token generated in 2 is validated for proper class (if
token is not generic) and proper user and must not have expired.
If everything is valid, call post_collection_inner to process the
input and generate the new entry.
To make recognition of 2 stable (so it's not confused with
rest/data/<:class_name>/<:item_id>), removed @ from
Routing::url_to_regex.
The current Routing.execute method stops on the first regular
expression to match the URL. Since item_id doesn't accept a POST, I
was getting 405 bad method sometimes. My guess is the order of the
regular expressions is not stable, so sometime I would get the right
regexp for /data/<class>/@poe and sometime I would get the one for
/data/<class>/<item_id>. By removing the @ from the url_to_regexp,
there was no way for the item_id case to match @poe.
There are alternate fixes we may need to look at. If a regexp matches
but the method does not, return to the regexp matching loop in
execute() looking for another match. Only once every possible match
has failed should the code return a 405 method failure.
Another fix is to implement a more sophisticated mechanism so that
@Routing.route("/data/<:class_name>/<:item_id>/<:attr_name>", 'PATCH')
has different regexps for matching <:class_name> <:item_id> and
<:attr_name>. Currently the regexp specified by url_to_regex is used
for every component.
Other fixes:
Made failure to find any props in props_from_args return an empty
dict rather than throwing an unhandled error.
Make __init__ for SimulateFieldStorageFromJson handle an empty json
doc. Useful for POSTing to rest/data/class/@poe with an empty
document.
Testing:
added testPostPOE to test/rest_common.py that I think covers
all the code that was added.
Documentation:
Add doc to rest.txt in the "Client API" section titled: Safely
Re-sending POST". Move existing section "Adding new rest endpoints" in
"Client API" to a new second level section called "Programming the
REST API". Also a minor change to the simple rest client moving the
header setting to continuation lines rather than showing one long
line.
| author | John Rouillard <rouilj@ieee.org> |
|---|---|
| date | Sun, 14 Apr 2019 21:07:11 -0400 |
| parents | 14a61eabcea8 |
| children |
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############################################################################## # # Copyright (c) 2001, 2002 Zope Corporation and Contributors. # All Rights Reserved. # # This software is subject to the provisions of the Zope Public License, # Version 2.0 (ZPL). A copy of the ZPL should accompany this distribution. # THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED # WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED # WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS # FOR A PARTICULAR PURPOSE # ############################################################################## # Modifications for Roundup: # 1. commented out zLOG references # 2. use roundup.anypy.urllib_ """ Generic expat-based XML parser base class. """ #import zLOG class XMLParser: ordered_attributes = 0 handler_names = [ "StartElementHandler", "EndElementHandler", "ProcessingInstructionHandler", "CharacterDataHandler", "UnparsedEntityDeclHandler", "NotationDeclHandler", "StartNamespaceDeclHandler", "EndNamespaceDeclHandler", "CommentHandler", "StartCdataSectionHandler", "EndCdataSectionHandler", "DefaultHandler", "DefaultHandlerExpand", "NotStandaloneHandler", "ExternalEntityRefHandler", "XmlDeclHandler", "StartDoctypeDeclHandler", "EndDoctypeDeclHandler", "ElementDeclHandler", "AttlistDeclHandler" ] def __init__(self, encoding=None): self.parser = p = self.createParser() # Make sure we don't get fed unicode strings in Python 2 as we # can't handle those if hasattr(self.parser, 'returns_unicode'): self.parser.returns_unicode = False if self.ordered_attributes: try: self.parser.ordered_attributes = self.ordered_attributes except AttributeError: #zLOG.LOG("TAL.XMLParser", zLOG.INFO, # "Can't set ordered_attributes") self.ordered_attributes = 0 for name in self.handler_names: method = getattr(self, name, None) if method is not None: try: setattr(p, name, method) except AttributeError: #zLOG.LOG("TAL.XMLParser", zLOG.PROBLEM, # "Can't set expat handler %s" % name) pass def createParser(self, encoding=None): global XMLParseError try: from Products.ParsedXML.Expat import pyexpat XMLParseError = pyexpat.ExpatError return pyexpat.ParserCreate(encoding, ' ') except ImportError: from xml.parsers import expat XMLParseError = expat.ExpatError return expat.ParserCreate(encoding, ' ') def parseFile(self, filename): self.parseStream(open(filename)) def parseString(self, s): self.parser.Parse(s, 1) def parseURL(self, url): import roundup.anypy.urllib_ self.parseStream(roundup.anypy.urllib_.urlopen(url)) def parseStream(self, stream): self.parser.ParseFile(stream) def parseFragment(self, s, end=0): self.parser.Parse(s, end)
