The tutorial includes references to various now more-or-less standard documents, or collections thereof, pertaining to Perl, databases and utf8.
]]>If you're in a hurry, jump to my latest (6th) Perl + jQuery tutorial.
In short: I don't use the clever jQuery add-on taconite because it supports only commands (verbs) and I needed conditional execution (an 'if').
Nevertheless, I pinched-er-adapted the idea to unilaterally update some parts of the DOM, and to conditionally update other parts.
Happy reading...
Here's an image displaying various options re SQL joins.
Wish I'd see this years, nay, decades, ago.
This is because I put the text of the entry in MT's 'Extended', and now I've just added this stuff to 'Body'.
Also, the 5th tut is on Autocomplete.
So... I've put some jQuery tutorials on-line.
I hope you have less pain with jQuery than I am having. I will stick to it, because it's certainly noticeably better than YUI.
OK. After a bit of pain I've set up an empty database for the
MusicBrainz database.
In particular, where they say 'sudo cpan Carton' you probably want 'cpanm Carton'.
This exercise was because, astonishingly, one of the users of my module GraphViz2 had doubts about it handling 149 tables spread over 4 schema.
The version of dbi.schema.pl shipped with GraphViz2 V 2.07 needed a patch to handle multiple schema, but after fixing that, you can view the SVG in all its ghastly glory.
Firstly, set up you env vars thusly:
env | grep DBI
DBI_PASS=musicbrainz
DBI_DSN=dbi:Pg:dbname=musicbrainz_db
DBI_SCHEMA=musicbrainz,cover_art_archive,report,statistics
DBI_USER=musicbrainz
Then the command is:
dbi.schema.pl svg musicbrainz.svg > musicbrainz.log
Further, you can download this set of files:
o musicbrainz.svg (size: 257,156 bytes)
o musicbrainz.log (output of dbi.schema.pl, containing the DOT file)
o dbi.schema.pl (patched)
o tables.log (the list of 149 tables as output by Pg's psql)
here.
I'll release a new GraphViz2 shortly.
1: COUNT
2: KEY_SEQ
3: FKTABLE_NAME
4: PKCOLUMN_NAME
5: FKCOLUMN_NAME
6: UPDATE_RULE
7: DELETE_RULE
8: UNKNOWN
If anyone can explain the last item, or offer corrections, please advise.
He and I have both had great difficulty getting GraphViz2 to properly display the schema of this database. He's using Strawberry Perl, and I'm using Perl under Debian.
Among the various problems are files marked as ISO-8859-1 but containing UTF8 data, and the Postgres data using the string syntax N'...'. AFAICS my Postgres V 8 (printed) manuals don't use this. Perhaps the original Chinook data was prepared by someone using Postgres V 9.
So, I've created Postgres and SQLite files to simplify installation of the Chinook data.
Download the Postgres data from here, and the SQLite data from here.
See create.pg.sh and create.sqlite.sh for the installation steps.
Note also that Postgres' psql and SQLite's sqlite3 both fail to handle UTF8 files starting with a BOM, so I've rigged the code in both cases to generate a deliberate syntax error when the reader attaches the BOM to the first non-comment token.
Recall also this quotation "Both Oracle and SQLite.org ship a program called sqlite3. They are not compatible. Which one are you using? I use the one from the SQLite.org." from the docs for my module WWW::Scraper::Wikipedia::ISO3166.
Lastly, my test files assume you're using GraphViz2 V 2.07.
I'm re-writing App::Office::Contacts, and making many internal changes.
Externally, little will change. (See also: Famous Last Words.)
The point of this post is to solicit feedback: If you're interested in these modules, or are worried about the changes, comment below, or email me directly.
Hopefully, however, no-one is using the module, so exactly the same number of people will be affected...
Some details:
Internal changes include:
o Switch from CGI::Application to CGI::Snapp
o Switch from CGI::Session to Data::Session
o Switch from Log::Dispatch to Log::Handler
o Switch from YUI to jQuery
o Restructure the class hierarchy
o For MySQL users, adopt engine=innodb
o Additions to the people table: facebook_id and twitter_id
o Old fields in the people table now ignored: broadcasts, communication_types
External changes:
o The appearance of each input form will be a bit different, mainly due to adopting jQuery
Future changes:
o I am aware the lack of sites/addresses (per org, per person) is a deficiency. That will be rectified shortly.
The companion modules App::Office::Contacts::Donations and App::Office::Contacts::Import::vCards will of course change to match.
]]>Yes, it's true:
Cheers
Here's a list of 30 url mappers I'd like to treat as per the list of 122 class builders. Please comment re adds or deletes, evaluation criteria, whatever.
Catalyst::Dispatcher
CGI::Application::Plugin::ActionDispatch
CGI::Application::Plugin::REST
CGI::Application::Plugin::Routes
CGI::Application::URIMapping
Dancer::Plugin::Dispatcher
Dancer::Route
Forward::Routes
HTTP::Router::Route
Jifty::Dispatcher
Mojolicious::Routes
Path::Dispatcher
Path::Router
Pickles::Dispatcher
Pinwheel::Mapper
Plack::App::Path::Router
Plack::App::Path::Router::PSGI
Plack::App::URLMap
PlackX::RouteBuilder
REST::Application::Routes
Router::Dumb
Router::Generic
Router::Simple
Routes::Tiny
Scaffold::Routes
Silki::Action::REST
Sleep::Routes
Web::API::Mapper
Web::Dispatcher::Simple
Web::Simple
Omitted: Apache-specific, FCGI-specific, Engine X-specific.
Here's a list of class builders which I'd like to turn into a task to assess them (I'd mentor it) for Google's code-in. If you have any suggestions (add, delete), please do so in the comments.
Assessment would include features, outstanding bugs, reviews, date of last update, whatever. Perhaps even speed.
accessors
accessors::fast
App::Benchmark::Accessors (Benchmarks the other modules)
Attribute::Property
AutoCode::AccessorMaker
Badger
Basset::Object
Class::Accessor
Class::Accessor::Assert
Class::Accessor::Chained
Class::Accessor::Children
Class::Accessor::Class
Class::Accessor::Classy
Class::Accessor::Complex
Class::Accessor::Constructor
Class::Accessor::Contextual
Class::Accessor::FactoryTyped
Class::Accessor::Fast
Class::Accessor::Fast::Contained
Class::Accessor::Fast::GXS
Class::Accessor::Fast::WithBuilder
Class::Accessor::Fast::XS
Class::Accessor::Grouped
Class::Accessor::Installer
Class::Accessor::Lite
Class::Accessor::Lite::Lazy
Class::Accessor::Lvalue
Class::Accessor::Named
Class::Accessor::Ref
Class::Accessor::Tiny
Class::Accessor::WithDefault
Class::AccessorMaker
Class::Adapter::Builder
Class::Attrib
Class::AutoAccess
Class::AutoClass
Class::Axelerator
Class::Builder
Class::Class
Class::Classgen
Class::Closure
Class::Colon
Class::Constructor
Class::Contract
Class::Data::Accessor
Class::Data::Inheritable
Class::Declare
Class::Delegate
Class::Delegation
Class::Dot
Class::Easy
Class::Field
Class::Fields (Obsolete)
Class::Frame
Class::Framework
Class::Generate
Class::Gomor
Class::Holon
Class::Hook
Class::InsideOut
Class::Light
Class::MakeMethods
Class::MakeMethods::Emulator::AccessorFast
Class::Maker
Class::Member
Class::Meta
Class::Meta::AccessorBuilder
Class::Meta::Express
Class::MethodMaker
Class::Monkey
Class::MOS (Special case)
Class::NamedParms
Class::ObjectTemplate
Class::Prototyped
Class::Root
Class::Scaffold::Accessor
Class::SelfMethods (Deprecated)
Class::Std
Class::Struct
Class::StructTemplate
Class::Tangram
Class::Template
Class::Trigger
Class::Virtual
Class::XSAccessor
Class::XSAccessor::Compat
classes
CodeGen::PerlBean
Data::AsObject
EntityModel::Class::Accessor
Hash::FieldHash
Hash::Objectify
Hash::Util::FieldHash
HTML::Mason::MethodMaker
Lexical::Attributes
Loompa
M
Mo
Moo
Moos
Moose (The heavy-weight one of the pack)
Moose::Tiny
Moose::Micro
MooseX::EasyAcc
MooseX::FollowPBP
MooseX::SemiAffordanceAccessor
Mouse
Object::Accessor
Object::Accessor::XS
Object::Botox
Object::Generic
Object::InsideOut
Object::Simple
Object::Tiny
Object::Tiny::Lvalue
OOP::Perlish::Class::Accessor
OOPS
Package::New
Reindeer
Simple::Accessor
Sub::Auto
Sub::Mage
I've released GraphViz2::Marpa::PathUtils V 1.01, which now offers an algorithm that performs auto-detection of clusters in Graphviz *.gv files, via the find_clusters() method.
Download, or read the docs at the usual place:
Peruse the demo.
The most complex input file I tested ran foul of a bug in Graphviz itself, which I've reported. I am using Graphviz V 2.26.3, and the bug has been kindly confirmed by Ryan Schimdt in 2.28.0 and 2.29.20121022.0445 on OS X. So, that image is not yet on the demo page.
Note: An option in the code allows outputting the resultant *.gv file, hence making it available for further processing, and the format of the (optional) output image (svg, png, ...) is also an option (which is passed to 'dot').
Note: Nodes and edges using ports are not yet supported.
Thanx to Ron Newman (on the Graphviz mailing list) for the suggestion to implement this (despite the complexity of the code I had to write :-).
Lastly, the previous algorithm in the module (in V 1.00), accessed via the find_fixed_length_paths() method, finds all paths of a given length starting from a given node. Demo output is included in the above URL.
]]>I wanted to title this post: The Tree::Hugger Chronicles: Tree, etc, but that was too long.
Anyway, I mention Forest only to say I won't mention it further.
I've become co-maint (or accidentally, owner) of various Tree-ish modules, so I thought I mention what's up. Each module is followed by an extract from the CHANGES file.
o Tree: I've just released V 1.03:
- Rename Tree::Binary to Tree::Binary2 so it no longer clashes with the Tree::Binary shipped in the Tree-Binary distro. MetaCPAN was getting confused, and automatically redirected links from this module's Tree:Binary to the other one.
o Tree:Binary: No activity.
o Tree::DAG_Node. I've just released V 1.06:
- Pre-emptive apologies for any changes which are not back-compat. No such problems are expected, but the introduction of new methods may disconcert some viewers.
- Fix RT#78858, reported by Gene Boggs. Audit code for similar problems.
- Fix RT#79506. reported by Ron Savage.
- Rename ChangeLog to CHANGES, and add Changelog.ini.
- Replace all uses of cyclicity_fault() and Carp::croak with die.
- Remove unused methods: decommission_root(), cyclicity_allowed(), cyclicity_fault(), inaugurate_root(), no_cyclicity() and _update_links(). OK - cyclicity_fault() was called once. It just died.
- Add methods: format_node(), hashref2string(), is_root(), node2string(), tree2string().
tree2string($opts, $node) - unlike draw_ascii_tree() - can optionally print the tree starting at any node. Override format_node(), hashref2string(), and node2string() if desired.
- Reformat the POD big-time.
- Add Build.PL.
- Re-write Makefile.PL.
- Remove use vars(@ISA $Debug $VERSION). Replace latter 2 with 'our ...'.
- Rename t/00_about_verbose.t to t/about.perl.t.
- Add scripts/cut.and.paste.subtrees.pl. Warning: Some trees get into an infinite loop.
- Add t/cut.and.paste.subtrees.t. Warning: Some trees get into an infinite loop.
- Document the options (discouraged by Sean) supported in the call to new($hashref).
o Tree::Persist. No activity.
In fact I'm not yet co-maint of this, due to a typo by $name_elided who removed himself as owner rather than make me co-maint.
A fix from the CPAN admins is taking so long I decided to volunteer to become an admin rather than complain, but that matter is still up in the air. Perhaps nothing will come of it.
Also, as I release updates, I'm adding some common POD to each. Just a See Also so far, with a little FAQ.
And why do this? Well, I've been doing a lot of work which required a tree data structure, will parsing Graphviz *.gv files, and ended up using Tree::DAG_Node after switching back and forth between it and Tree, because the former is so good. But I'm aware it was criticised for having no meaningful tests, so I wrote a test which cuts-and-pastes a few sub-trees. But be warned, such code can easily get into an infinite loop, so don't copy it mindlessly.
As for the Graphviz work, that deserves a separate blog entry.
Neither I nor Sean Burke can get a response from David, bit if anyone knows him, please let him know I'd like to take co-maint of Tree::DAG_Node in order to fix bugs.
So, I'll ask the CPAN admins on Friday to do that if I don't hear from him beforehand.
If he doesn't want me to be co-maint, I'll fork the code...
]]>If you're using AT&T's Graphviz and you're interested in finding fixed length paths thru your graphs, there's a new module to help.
You'll need Marpa, and GraphViz2, and GraphViz2::Marpa. These will be installed as pre-reqs.
Then all you need is GraphViz2::Marpa::PathUtils, after it hits CPAN.
You can start reading the docs here.
Cheers
