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view roundup/cgi/TAL/README.txt @ 5525:bb7865241f8a
Make CSV import/export compatible across Python versions (also RDBMS journals) (issue 2550976, issue 2550975).
The roundup-admin export and import commands are used for migrating
between different database backends. It is desirable that they should
be usable also for migrations between Python 2 and Python 3, and in
some cases (e.g. with the anydbm backend) this may be required.
To be usable for such migrations, the format of the generated CSV
files needs to be stable, meaning the same as currently used with
Python 2. The export process uses repr() to produce the fields in the
CSV files and eval() to convert them back to Python data structures.
repr() of strings with non-ASCII characters produces different results
for Python 2 and Python 3.
This patch adds repr_export and eval_import functions to
roundup/anypy/strings.py which provide the required operations that
are just repr() and eval() in Python 2, but are more complicated in
Python 3 to use data representations compatible with Python 2. These
functions are then used in the required places for export and import.
repr() and eval() are also used in storing the dict of changed values
in the journal for the RDBMS backends. It is similarly desirable that
the database be compatible between Python 2 and Python 3, so that
export and import do not need to be used for a migration between
Python versions for non-anydbm back ends. Thus, this patch changes
rdbms_common.py in the places involved in storing journals in the
database, not just in those involved in import/export.
Given this patch, import/export with non-ASCII characters appear based
on some limited testing to work across Python versions, and an
instance using the sqlite backend appears to be compatible between
Python versions without needing import/export, *if* the sessions/otks
databases (which use anydbm) are deleted when changing Python version.
| author | Joseph Myers <jsm@polyomino.org.uk> |
|---|---|
| date | Sun, 02 Sep 2018 23:48:04 +0000 |
| parents | b9988e118055 |
| children |
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TAL - Template Attribute Language --------------------------------- This is an implementation of TAL, the Zope Template Attribute Language. For TAL, see the Zope Presentation Templates ZWiki: http://dev.zope.org/Wikis/DevSite/Projects/ZPT/FrontPage It is not a Zope product nor is it designed exclusively to run inside of Zope, but if you have a Zope checkout that includes Products/ParsedXML, its Expat parser will be used. Prerequisites ------------- You need: - A recent checkout of Zope2; don't forget to run the wo_pcgi.py script to compile everything. (See above -- this is now optional.) - A recent checkout of the Zope2 product ParsedXML, accessible throught <Zope2>/lib/python/Products/ParsedXML; don't forget to run the setup.py script to compiles Expat. (Again, optional.) - Python 1.5.2; the driver script refuses to work with other versions unless you specify the -n option; this is done so that I don't accidentally use Python 2.x features. - Create a .path file containing proper module search path; it should point the <Zope2>/lib/python directory that you want to use. How To Play ----------- (Don't forget to edit .path, see above!) The script driver.py takes an XML file with TAL markup as argument and writes the expanded version to standard output. The filename argument defaults to tests/input/test01.xml. Regression test --------------- There are unit test suites in the 'tests' subdirectory; these can be run with tests/run.py. This should print the testcase names plus progress info, followed by a final line saying "OK". It requires that ../unittest.py exists. There are a number of test files in the 'tests' subdirectory, named tests/input/test<number>.xml and tests/input/test<number>.html. The Python script ./runtest.py calls driver.main() for each test file, and should print "<file> OK" for each one. These tests are also run as part of the unit test suites, so tests/run.py is all you need. What's Here ----------- DummyEngine.py simple-minded TALES execution engine TALInterpreter.py class to interpret intermediate code TALGenerator.py class to generate intermediate code XMLParser.py base class to parse XML, avoiding DOM TALParser.py class to parse XML with TAL into intermediate code HTMLTALParser.py class to parse HTML with TAL into intermediate code HTMLParser.py HTML-parsing base class driver.py script to demonstrate TAL expansion timer.py script to time various processing phases setpath.py hack to set sys.path and import ZODB __init__.py empty file that makes this directory a package runtest.py Python script to run file-comparison tests ndiff.py helper for runtest.py to produce diffs tests/ drectory with test files and output tests/run.py Python script to run all tests Author and License ------------------ This code is written by Guido van Rossum (project lead), Fred Drake, and Tim Peters. It is owned by Digital Creations and can be redistributed under the Zope Public License. TO DO ----- (See also http://www.zope.org/Members/jim/ZPTIssueTracker .) - Need to remove leading whitespace and newline when omitting an element (either through tal:replace with a value of nothing or tal:condition with a false condition). - Empty TAL/METAL attributes are ignored: tal:replace="" is ignored rather than causing an error. - HTMLTALParser.py and TALParser.py are silly names. Should be HTMLTALCompiler.py and XMLTALCompiler.py (or maybe shortened, without "TAL"?) - Should we preserve case of tags and attribute names in HTML?