Mercurial > p > roundup > code
view roundup/cgi/TAL/TALParser.py @ 6565:2c2dbfc332ba
Try to handle multiple connections better.
The session database is a hot spot. When multiple requests (e.g. 20)
come in at the same time session database contention can get great.
The original code didn't retry session database access when the open
failed. This resulted in errors at the client.
The second pass delayed 0.01 seconds and retried. It was better but we
still had multiple second stalls. I think the first request got in,
everybody else backed up and then retried at the same time. Again they
stepped on each other. With logging I would see many counters go all
the way to low single digits or to -1 indicating falure.
This pass uses randomint to generate delays from 0-.125 seconds in 5ms
increments. This performs better in testing. I rarely saw a counter
less than 13 (2 failed retries). Current logging starts after 6
failures and counts down until success or failure.
| author | John Rouillard <rouilj@ieee.org> |
|---|---|
| date | Thu, 16 Dec 2021 20:02:00 -0500 |
| parents | 23b8e6067f7c |
| 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. # ############################################################################## """ Parse XML and compile to TALInterpreter intermediate code. """ from .XMLParser import XMLParser from .TALDefs import XML_NS, ZOPE_I18N_NS, ZOPE_METAL_NS, ZOPE_TAL_NS from .TALGenerator import TALGenerator class TALParser(XMLParser): ordered_attributes = 1 def __init__(self, gen=None): # Override XMLParser.__init__(self) if gen is None: gen = TALGenerator() self.gen = gen self.nsStack = [] self.nsDict = {XML_NS: 'xml'} self.nsNew = [] def getCode(self): return self.gen.getCode() def getWarnings(self): return () def StartNamespaceDeclHandler(self, prefix, uri): self.nsStack.append(self.nsDict.copy()) self.nsDict[uri] = prefix self.nsNew.append((prefix, uri)) def EndNamespaceDeclHandler(self, prefix): self.nsDict = self.nsStack.pop() def StartElementHandler(self, name, attrs): if self.ordered_attributes: # attrs is a list of alternating names and values attrlist = [] for i in range(0, len(attrs), 2): key = attrs[i] value = attrs[i+1] attrlist.append((key, value)) else: # attrs is a dict of {name: value} attrlist = sorted(attrs.items()) # Sorted for definiteness name, attrlist, taldict, metaldict, i18ndict \ = self.process_ns(name, attrlist) attrlist = self.xmlnsattrs() + attrlist self.gen.emitStartElement(name, attrlist, taldict, metaldict, i18ndict) def process_ns(self, name, attrlist): taldict = {} metaldict = {} i18ndict = {} fixedattrlist = [] name, namebase, namens = self.fixname(name) for key, value in attrlist: key, keybase, keyns = self.fixname(key) ns = keyns or namens # default to tag namespace item = key, value if ns == 'metal': metaldict[keybase] = value item = item + ("metal",) elif ns == 'tal': taldict[keybase] = value item = item + ("tal",) elif ns == 'i18n': assert 0, "dealing with i18n: " + repr((keybase, value)) i18ndict[keybase] = value item = item + ('i18n',) fixedattrlist.append(item) if namens in ('metal', 'tal', 'i18n'): taldict['tal tag'] = namens return name, fixedattrlist, taldict, metaldict, i18ndict def xmlnsattrs(self): newlist = [] for prefix, uri in self.nsNew: if prefix: key = "xmlns:" + prefix else: key = "xmlns" if uri in (ZOPE_METAL_NS, ZOPE_TAL_NS, ZOPE_I18N_NS): item = (key, uri, "xmlns") else: item = (key, uri) newlist.append(item) self.nsNew = [] return newlist def fixname(self, name): if ' ' in name: uri, name = name.split(' ') prefix = self.nsDict[uri] prefixed = name if prefix: prefixed = "%s:%s" % (prefix, name) ns = 'x' if uri == ZOPE_TAL_NS: ns = 'tal' elif uri == ZOPE_METAL_NS: ns = 'metal' elif uri == ZOPE_I18N_NS: ns = 'i18n' return (prefixed, name, ns) return (name, name, None) def EndElementHandler(self, name): name = self.fixname(name)[0] self.gen.emitEndElement(name) def DefaultHandler(self, text): self.gen.emitRawText(text) def test(): import sys p = TALParser() file = "tests/input/test01.xml" if sys.argv[1:]: file = sys.argv[1] p.parseFile(file) program, macros = p.getCode() from .TALInterpreter import TALInterpreter from .DummyEngine import DummyEngine engine = DummyEngine(macros) TALInterpreter(program, macros, engine, sys.stdout, wrap=0)() if __name__ == "__main__": test()
