view roundup/cgi/TAL/TALParser.py @ 6610:db3f0ba75b4a

Change checkpoint_data and restore_connection_on_error to subtransaction checkpoint_data and restore_connection_on_error used to commit() and rollback() the db connection. This causes additional I/O and load. Changed them to use 'SAVEPOINT name' and 'ROLLBACK TO name' to get a faster method for handling errors within a tranaction. One thing to note is that postgresql (unlike SQL std) doesn't overwrite an older savepoint with he same name. It keeps all savepoints but only rolls back to the newest one with a given name. This could be a resource issue. I left a commented out release statement in case somebody runs into an issue due to too many savepoints. I expect it to slow down the import but....
author John Rouillard <rouilj@ieee.org>
date Sat, 29 Jan 2022 11:29:36 -0500
parents 23b8e6067f7c
children
line wrap: on
line source

##############################################################################
#
# 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()

Roundup Issue Tracker: http://roundup-tracker.org/