On Thu, 19 Jul 2012, Roman Chyla wrote:
The script must have thought about it somehow :-) Have a great,
undisturbed vacation!
In rev 1363436 of jcc, I implemented support for the simplest version of the
proposal via a new command line flag, off by default, called
--use_full_names.
When --use_full_names is used, the wrapped classes get installed into a
Python module hierarchy that parallels the Java one.
For example:
>>> import lucene
>>> lucene.initVM()
<jcc.JCCEnv object at 0x10029c0f0>
>>> from org.apache.lucene.document import Document
>>> Document()
<Document: Document<>>
>>>
Andi..
roman
On Thu, Jul 19, 2012 at 9:33 AM, Andi Vajda <va...@apache.org> wrote:
On Fri, 13 Jul 2012, Roman Chyla wrote:
Hi,
I was playing with the idea of creating virtual packages, attached is a
working script that illustrates it. I am getting this output:
Dit it work?
No, I haven't forgotten, I'm just on vacation.
Andi..
==================
from org.apache.lucene.search import SearcherFactory; print
SearcherFactory
<type 'SearcherFactory'>
from org.apache.lucene.analysis import Analyzer as Banalyzer; print
Banalyzer
<type 'Analyzer'>
print sys.modules['org'] <module 'org' (built-in)>
print sys.modules['org.apache'] <module 'org.apache' (built-in)>
print sys.modules['org.apache.lucene'] <module 'org.apache.lucene'
(built-in)>
print sys.modules['org.apache.lucene.search'] <module
'org.apache.lucene.search' (built-in)>
Cheers,
roman
On Fri, Jul 13, 2012 at 1:34 PM, Andi Vajda <va...@apache.org> wrote:
On Jul 13, 2012, at 18:33, Roman Chyla <roman.ch...@gmail.com> wrote:
I think this would be great. Let me add little bit more to your
observations (whole night yesterday was spent fighting with renames -
because I was building a project which imports shared lucene and solr
--
there were thousands of same classes, I am not sure it would be possible
without some sort of a flexible rename...)
JCC is a great tool and is used by potentially many projects - so
stripping
"org.apache" seems right for pylucene, but looks arbitrary otherwise
Yes, I forgot to say that there would be a way to declare one or more
mappings so that org.apache.lucene becomes lucene.
Andi..
(unless there is a flexible stripping mechanism). Also, if the full
namespace remains original, then the code written in Python would be
also
executable by Jython, which is IMHO an advantage.
But this being Python, the packages cannot be spread in different
locations
(ie. there can be only one org.apache.lucene.analysis package) - unless
there exists (again) some flexible mechanism which populates the
namespace
with objects that belong there. It may seem an overkill to you, because
for
single projects it would work, but seems perfectly justifiable in case
of
imported shared libraries
I don't know what is your idea for implementing the python packages, but
your last email got me thinking as well - there might be a very simple
way
of getting to the java packages inside Python without too much work.
Let's say the java "org.apache.lucene.search.IndexSearcher" is known to
python as org_apache_lucene_search_IndexSearcher
and users do:
import lucene
lucene.initVM()
initVM() first initiates java VM (and populates the lucene namespace
with
all objects), but then it will call jcc.register_module(self)
A new piece of code inside JCC grabs the lucene module and creates (on
the
fly) python packages -- using types.ModuleType (or new.module()) -- the
new
packages will be inserted into sys.modules
so after lucene.initVM() returns
users can do "from org.apache.lucene.search import IndexSearcher" and
get
lucene.org_apache_lucene_search_IndexSearcher object
and also, when shared libraries are present (let's say 'solr') users do:
import solr
solr.initVM()
The JCC will just update the existing packages and create new ones if
needed (and from this perspective, having fully qualified name is safer
than to have lucene.search.IndexSearcher)
I think this change is totally possible and will not change the way how
extensions are built. Does it have some serious flaw?
I would be of course more than happy to contribute and test.
Best,
roman
On Fri, Jul 13, 2012 at 11:47 AM, Andi Vajda <va...@apache.org> wrote:
On Tue, 10 Jul 2012, Andi Vajda wrote:
I would also like to propose a change, to allow for more flexible
mechanism of generating Python class names. The patch doesn't change
the default pylucene behaviour, but it gives people a way to replace
class names with patterns. I have noticed that there are more
same-name classes from different packages in the new lucene (and it
becomes worse when one has to deal with both lucene and solr).
Another way to fix this is to reproduce the namespace hierarchy used
in
Lucene, following along the Java packages, something I've been
dreading to
do. Lucene just loooooves a really long deeply nested class structure.
I'm not convinced yet it is bad enough to go down that route, though.
Your proposal to use patterns may in fact yield a much more convenient
solution. Thanks !
Rethinking this a bit, I'm prepared to change my mind on this. Your
patterned rename patch shows that we're slowly but surely reaching the
limit of the current setup that consists in throwing all wrapped
classes
under the one global 'lucene' namespace.
Lucene 4.0 has seen a large number of deeply nested classes with
similar
names added since 3.x. Renaming these one by one (or excluding some)
doesn't scale. Using the proposed patterned rename scales more but
makes it
difficult to know what got renamed and how.
Ultimately, the more classes that are like-named, the more classes
would
have instable names from one release to the next as more duplicated
names
are encountered.
What if instead JCC supported the original Java namespaces all the way
to
the Python inteface (still dropping the original 'org.apache' Java
package
tree prefix) ?
The world-rooted style of naming Java classes isn't Pythonic but using
the
second half of the package structure feels right at home in the Python
world.
JCC already re-creates the complete Java package structure in C++ as
namespaces for all the C++ code it generates, for both the JNI wrapper
classes and the C++/Python types. It's only the installation of the
class
names into the Python VM that is done in the flat 'lucene' namespace.
I think it shouldn't be too hard to change the code that installs
classes
to create sub-modules of the lucene module and install classes in these
submodules instead (down to however many levels are in the original).
In other words:
- from lucene import Document
would become
- from lucene.document import Document
One could of course also say:
- import lucene.document.Document as whateverOneLikes
If that proposal isn't mortally flawed somewhere, I'm prepared to drop
support for --rename and replace it with this new Python class/module
layout.
Since this is being talked about in the context of a major PyLucene
release, version 4.0, and that all tests/samples have to be reworked
anyway, this backwards compat break shouldn't be too controversial,
hopefully.
If it is, the old --rename could be preserved for sure, but I'd prefer
simplying the JCC interface than to accrete more to it.
What do you think ?
Andi..
Andi..
I can confirm the test_test_BinaryDocument.py crashes the JVM no
more.
Roman
On Tue, Jul 10, 2012 at 8:54 AM, Andi Vajda <va...@apache.org> wrote:
Hi Roman,
On Mon, 9 Jul 2012, Roman Chyla wrote:
Thanks, I am attaching a new patch that adds the missing test base.
Sorry for the tabs, I was probably messing around with a few
editors
(some of them not configured properly)
I integrated your test class (renaming it to fit the naming scheme
used).
Thanks !
So far, found one serious problem, crashes VM -- see. eg
test/test_BinaryDocument.py - when getting the document using:
reader.document(0)
test/test_BInaryDocument.py doesn't seem to crash the VM but fails
because
of some API changes. I suspect the crash to be some issue related to
using
an older jcc.
I see a comment saying: "couldn't find any combination with
lucene4.0
where
it would raise errors". Most of these unit tests are straight ports
from the
original Java version. If you're stumped about a change, check the
original
Java test, it may have changed too.
Andi..
