Frozen Perl 2010

It's been a long week, culminating today in Frozen Perl 2010, a Perl conference for and by Perl hackers, here in the Twin Cities. I gave two talks at today's conference, one on Swish3 and the other on Devel::NYTProf and Search::Tools. Both talks seemed well-received.

In the process of preparing the talks I also released a few new, related modules to CPAN this week:

Search::OpenSearch

OpenSearch server glue for KinoSearch and Swish-e 2.x via SWISH::Prog. There's a demo Plack app and ExtJS, using both search engines as part of the slides for my Swish3 talk.

I think OpenSearch is very cool and look forward to doing more with that spec, including adding more features (e.g. facets) to Search::OpenSearch.

Search::Query

Search::Query now has support for SQL and SWISH Dialects. I hope to add KinoSearch and Xapian dialects soon. The Search::Query::Parser now has (undocumented and experimental) support for range queries, so that you can say:

foo=( 1..4 )

and that'll be expanded to

foo=( 1 OR 2 OR 3 OR 4 )

when the Dialect query object is stringified. Handy for things like ranges of dates, which is how I am using it as $work.

Search::Tools, SWISH::API::*

New releases of these older modules as well, with some bug fixes and refactoring to support the Search::Query.

So, yes. A busy week.

I enjoyed hearing other folks' talks today at Frozen Perl. There was a good variety: pack/unpack, Unicode, i18n and best practice-related presentations. I met some new people, renewed friendships with folks I already knew, and drank lots of free coffee. The cookies were good too.

File under projects/swish Sat Feb 6 23:27:19 CT 2010

SWISH::Prog::KSx and SWISH::Prog::Xapian on CPAN

Uploaded first pass at both implementations this last week. The announcement to the Swish-e list just went out.

File under projects/swish Mon Nov 30 22:19:26 CT 2009

SWISH::3 on CPAN

After 4 years of learning how to glue Perl and C together with XS and many sleepless nights, I have released SWISH::3 to the CPAN.

<cue the sound of scattered applause>

Mostly this is a triumph of longevity rather than quality code. It's taken me this long to get something workable.

File under projects/swish Fri Nov 20 22:02:44 CT 2009

swish_xapian

The Xapian backend for Swish3 has been getting some love lately. The swish_xapian command line tool has most of the features now that swish-e v2.x does.

I've posted about it on the Swish-e wiki.

File under projects/swish Wed Nov 18 23:22:11 CT 2009

Building Swish3 on OS X 10.6

I just wasted many hours trying to figure out why libswish3 failed to pass all tests on 10.6.

This link explains what I figured out to be true the hard way:

If I forced 32bit compile all is well:

While I would like to figure out how to compile as a native 64bit app, my MacBook has too many libs from before the 10.5 to 10.6 upgrade to trust that all the dep chain is 64bit compat.

The error I was seeing was the noxious BAD_ADDRESS error which traced back to some libxml2 hash features. Red herring. Of course, I had to recompile libxml2 with the -m32 as well so that everything was 32bit compatible. Took me hours before I noticed that the older working version on the same box was about half the size of the new version... which triggered the ol' 32-vs-64-bit thing in my brain.

Update: In the end this was a bug in libswish3 with confusing naming of some variables. But the 64-bit thing was a Good Thing To Realize.

File under projects/swish Mon Oct 5 23:05:50 CT 2009

Roy Tennant Interview

Roy resurrected the Swish-e project nearly 10 years ago. There's a nice interview with him out recently, in which he says "there really isn't anything I can't do with Perl and my favorite indexing tool, Swish-e" -- which is exactly my experience too.

Thanks, Roy.

File under projects/swish Sat Mar 28 21:14:16 CT 2009

Xapian, KinoSearch

I'm starting in (again) on KS and Xapian backends for SWISH::Prog, using libswish3.

I just downloaded the latest Xapian release (1.0.10) and latest KS from svn. I started the build process for Xapian first, then svn up'd KS and started the KS build. The KS build finished, and all tests passed, before Xapian even finished its build. That could be due to the speed of the gcc vs g++ compilers. Dunno. It was just a startling thing to notice.

Now back to writing code...

File under projects/swish Tue Dec 30 20:15:45 CT 2008

Swish3 Status 19 Sept 2008

A long hiatus for a full summer and then some contract work.

Some benchmarks of the latest tokenization algorithm shows that pure-ASCII tokenization is about 20% faster and UTF-8 tokenization is about 2% slower. So I'll take it.

Benchmark was performed by using perl/docmaker.pl to generate 100 random "docs" in both encodings (ASCII and random UTF-8) and then timed using swish_lint with and without the -t option.

Also recently fixed some failing tests on Linux and a memory warning.

File under projects/swish Fri Sep 19 05:33:31 CT 2008

Tests

Swish3 has a lot more tests that Swish-e (not counting Josh Rabinowitz's excellent testing package). And as of tonight all Swish3 tests are passing under both Linux 2.6 (CentOS 5) and OS X 10.4. \o/

File under projects/swish Thu Sep 18 22:54:29 CT 2008

Years pass, code grows, expectations ... ?

It's the OSCON time of year again. A couple of years ago I was in a hotel in Portland OR, coding up a KinoSearch implementation of Swish3. That was then. Two years later, Swish3 is really no further on, except that it has been largely refactored and is a much more stable, yet alpha, project.

Just remembering that tonight as I update the Perl bindings of Swish3 to use the new tokenization routines. It's the kind of project that moves in fits and starts. I would have liked to have finished it years ago, but it would not be as good, since many of the refactorings I have made over the last couple of years have been the direct result of coding strategies I have learned in my $job(s) and other FOSS projects.

And I find I like my life this way, chipping away at building a better mousetrap while I sip New Belgium beer and listen to Robert Plant and Alison Krauss. Sure, it's a sultry July evening, and my entire life occasionally floats through my mind like a grainy day at the beach, but hey: you only get this chance once, and building a better mousetrap is not a bad way to pass some idle moments.

File under projects/swish Thu Jul 24 21:46:09 CT 2008

Swish3 Status 19 April 2008

There's been quite a bit of activity in the last month.

• The C++ Xapian example now can search as well as index, and there are Perl equivalents using Search::Xapian checked into svn as well. The C++ code will read/write the swish.xml header; the Perl does not (yet).
• The meta/prop id unique check now uses a hash for quick look up.
• The test suite for libswish3 is totally restructured. Now using Perl's Test::Harness and added a slew of new meta/prop tests. Alongside that were additions to the NamedBuffer debugging output to print each substring in the buffer.
• Several new string-related utility functions for converting ints to strings and back. Also a new config hash for configration options that use a StringList instead of a simple string.
• Fixed some mem leaks in the example .c programs and added more info to the swish_lint usage() output (including reminders about the various SWISH_DEBUG* env var values).

There are still several parser features yet to be implemented to support the Swish-e 2.4 config options, but those will likely take a backseat to getting a working swish3 Perl script running with SWISH::Prog and SWISH::Prog::Xapian.

File under projects/swish Sat Apr 19 22:42:14 CT 2008

Swish3 Status 30 March 2008

More progress with Swish3.

• There is now a swish_xapian.cpp C++ example for using libswish3 with a Xapian backend. All that is complete is the indexing portion; still TODO is the search part. Still, a significant thing that it was so easy to build a search engine.
• The swish.xml header format is complete and can now read/write the header file. Need to add that part to the swish_xapian.cpp example.
• Squashed some long-standing memory leaks when using the filehandle functions.

Little by little.

File under projects/swish Sun Mar 30 22:03:48 CT 2008

Swish3 Status 2008-03-15

I've finally gotten back to Swish3 development after several months away. Hard to believe I've been working on this project for something close to 3 years now.

Lately I have been focusing on the following things:

Header file format

Because Swish3 will have multiple IR backends, it is important that there be a consistent index metadata file that describes the MetaNames, Properties, and tokenizing information, just like the Swish2 header does. Just as with the config file format, it makes sense to define the header file format as XML, since we already have a robust XML parser for free. To make it simple, I have defined the header file XML schema to be the same as the config file schema. In short, you configure Swish3 by creating a header file. The "real" header file will be more strict about explicitly naming all the expected attribute values, numbering the MetaName/Property ids, etc. But the idea is simple: a single XML schema.

I have written the code to read header/config file format and create a swish_Config object. There's also code for merging 2 swish_Config objects together, so that you can define a config file to override an existing header file.

Still TODO is the code for writing the header file.

The Perl bindings have been updated to reflect the new swish_Config API. This required a great deal of reworking and thinking about the Perl API. I had to rewrite things a few times to get a workable solution. The key Perl mantra is "objects on demand." I.e., do not define any Perl objects that wrap C pointers and try to keep them on the XS side. Instead, create all Perl objects "just in time" as part of the get_* method call. This makes reference counting much simpler.

MetaNames and PropertyNames

These now have their own C API with swish_MetaName and swish_Property structs. These relate directly to the header file format and swish_Config. There will end up being a separate PropertyName API for search results. I still think we're going to have to port the Swish2 PropertyNames storage/retrieval code to Swish3 and have a backend-indepedent index.prop file. The issue with this is going to be scaling. One other thought I've had is storing properties in a SQLite db. That route won't allow for presorted properties, but does have the advantage of being much more transparent and de-buggable.

SWISH::Prog

I have moved the SWISH::Prog svn tree to svn.swish-e.org from peknet.com. I also moved SWISH::Filter (and likely will eventually move SWISH::API::More and its cousins).

SWISH::Prog will form the framework for the Perl implementation of Swish3. I know there are some folks who don't like the idea of Swish3 being so Perl-centric. To that I can say only, tough luck. :)

Seriously though, my perspective is that there will be multiple Swish3 implementations. The one I am working on is in Perl using SWISH::Prog. There's nothing to stop someone from implementing one in C or C++ or Java or whatever. libswish3 provides the parsing/tokenizing piece missing from other IR projects, and it is a library for the very reason that implementing a Swish3 program should be language-neutral. If you can link against a C library, then you can write a Swish3 program. The header file API is well documented; the backend is supposed to be pluggable. It's all about the API.

I do intend to write a swish_xapian.cpp program eventually, showing how to implement a C++ Swish3 program with Xapian. That could be the fallback program if you really don't want to use Perl.

Documentation

I've stared a swish_intro.7 and swish_migration.7 set of docs. swish_intro will outline the aggregator/normalizer/analyzer/indexer/searcher philosophy and the outline of the libswish3 API. swish_migration will discuss differences in Swish2 vs Swish3 and how you can convert your config files and move to using Swish3.

File under projects/swish Sat Mar 15 22:23:14 CT 2008

Xapian 1.0 Released

Announced this morning.

Now if only I could find time to finish the swishx Swish3 example program...

File under projects/swish Fri May 18 09:00:48 CT 2007

Open Source Search Tools

I was answering an email tonight from the hyperestraier list about Xapian and Lucene and KinoSearch, and as I was googling around to find all the email threads I remembered being a part of on the topic, it was interesting to see intersections I hadn't remembered, like how the same people (like me) keep popping up around these tools.

There are some folks who just need to implement a search engine for their website/company/intranet. These are the sysadmin types who just need something that works so that they can move on to the next project.

Then there are folks working in the IR field itself who are trying to build the Next Big Search Thing, following in google tradition. Good luck to them. They'll need it.

Then there are folks like me, who are a little OCD over things like IR and search. I consider the developers of the projects I list above in that camp. It's a good camp to be in.

Open source search tools have come a long way and there is really some good momentum now in implementing multiple terabyte, high volume search projects using open source technology. I like working in IR at a time like this. Hopeful. Almost. :)

File under projects/swish Fri May 11 20:56:58 CT 2007

Swish3 Original Email

Was looking back through my email related to Swish3 and found the original thread in which I describe the idea to the developer list.

The historian in me thought it would be good to preserve that link somewhere. And I notice that original post was over 18 months ago. A (relatively) long time.

File under projects/swish Sat Apr 14 20:36:52 CT 2007

Tokenizing

Marvin's got some good remarks on Perl's UTF-8 regexp vis-a-vis tokenizing strings. His remarks are timely, as I have been spending/wasting time lately in libswish3's C tokenizing functions. My goal was to replace them with Perl regexp matching, but that may have been pre-mature given Marvin's remarks.

File under projects/swish Thu Mar 15 21:18:11 CT 2007