1. Hacking Movable Type
A guide for developers
Six Apart Ltd.
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2. Developing for Movable Type in 2 Days
• Day 1: The Basics
– Plugin Structure
– The Registry
– ConfiguraEon DirecEves
– Template Tags
– Objects
– Callbacks
• Day 2: Building User Interfaces
– Menus
– New ApplicaEon Screens
– Dialogs
– LisEng Screens
2
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3. Course Prerequisites
• This course requires that you have access to a
working Movable Type installa:on.
• This course also assumes that you are familiar
with basic system administra:on tasks, such
as copying and ediEng files.
• Finally, this course requires knowledge of the
Perl programming language.
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4. About Hacking
• What makes a good programmer?
• Use the source Luke.
• Copy and paste is your friend.
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5. Developing for Movable Type in 2 Days
• Day 1: The Basics
➡ Plugin Structure
– The Registry
– ConfiguraEon DirecEves
– Template Tags
– Objects
– Callbacks
• Day 2: Building User Interfaces
– Menus
– New ApplicaEon Screens
– Dialogs
– LisEng Screens
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6. Plugin Structure
• Your config file
– plugins/MyPlugin/config.yaml
• Your library files
– plugins/MyPlugin/lib/*
• Your templates
– plugins/MyPlugin/tmpl/*
• Your staEc images, javascript and CSS files
– mt-static/plugins/MyPlugin/*
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7. Plugin Structure
• Other important files and directories
– MyPlugin-README.txt
– MyPlugin-LICENSE.txt
– plugins/MyPlugin/t/*
– plugins/MyPlugin/extlib/*
– plugins/MyPlugin/php/*
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8. Plugin Packaging
• Files that really help with the packaging and
distribuEon of an enEre plugin:
– Makefile.PL
– MANIFEST.SKIP
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9. Makefile.PL
use ExtUtils::MakeMaker;
WriteMakefile(
NAME => quot;My Plugin's Display Namequot;,
VERSION => '1.1',
DISTNAME => 'MyPlugin',
);
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10. MANIFEST.SKIP
# version control
bCVS
(^|/).
# CPAN chain files
^MANIFEST
^Makefile
^META.yml$
^blib/
~$
# packages
.zip$
.tar.gz$
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11. CreaEng a Plugin Zip File
These simple sequence of commands:
> perl Makefile.PL
> make manifest
> make zipdist
Will produce the perfect MT Plugin zip file:
• MyPlugin‐1.1.zip
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12. Developing for Movable Type in 2 Days
• Day 1: The Basics
– Plugin Structure
➡ The Registry
– ConfiguraEon DirecEves
– Template Tags
– Objects
– Callbacks
• Day 2: Building User Interfaces
– Menus
– New ApplicaEon Screens
– Dialogs
– LisEng Screens
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13. The Movable Type Registry
• Movable Type is a config‐driven applicaEon.
• The “registry” is where Movable Type stores its
configuraEon.
• Each plugin provides a mini‐registry file, config.yaml,
that defines its feature set.
• The config.yaml file is then merged into Movable
Type’s main registry.
• Every plugin therefore is 50% configuraEon and 50%
code.
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14. config.yaml
name: Fluid App
id: FluidApp
author_link: http://www.majordojo.com/
author_name: Byrne Reese
description: This plugin provides enhanced support for Fluid.
version: 0.90
plugin_link: http://www.majordojo.com/projects/mt-fluid-app.php
applications:
cms:
methods:
fluid_update: $FluidApp::FluidApp::Plugin::cms_update
callbacks:
MT::App::CMS::template_source.header: $FluidApp::…::Plugin::xfrm
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15. Yikes
What is all that?
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16. A YAML Primer
• YAML == “Yet Another Markup Language”
• XML AlternaEve
• Less verbose
• Human readable and writable
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17. XML vs. YAML
<?xml version=quot;1.0quot;>
<address>
<first_name>Byrne</first_name>
<last_name>Reese</last_name>
<email>byrne@majordojo.com</email>
<company>
<name>Six Apart, Ltd.</name>
<street_address>
548 4th Street, San Francisco, CA 94107
</street_address>
</company>
</address>
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18. XML vs. YAML
address:
first_name: Byrne
last_name: Reese
email: byrne@majordojo.com
company:
name: Six Apart, Ltd.
street_address: 548 4th Street,
San Francisco, CA 94107
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19. Your First Plugin
Place this in: plugins/Good4Nothing/config.yaml
name: Good for Nothing Plugin for Movable Type
id: Good4Nothing
key: Good4Nothing
author_link: http://www.yourwebsite.com/
author_name: Your Name Here
description: This plugin is an example plugin.
version: 1.0
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20. Developing for Movable Type in 2 Days
• Day 1: The Basics
– Plugin Structure
– The Registry
➡ Configura:on Direc:ves
– Template Tags
– Objects
– Callbacks
• Day 2: Building User Interfaces
– Menus
– New ApplicaEon Screens
– Dialogs
– LisEng Screens
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21. Adding a Config DirecEve
• What is a configuraEon direcEve?
• When should you use a config direcEve?
• What are the alternaEves?
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22. Adding a Config DirecEve
name: Good for Nothing Plugin for Movable Type
id: Good4Nothing
key: Good4Nothing
author_link: http://www.yourwebsite.com/
author_name: Your Name Here
description: This plugin is an example plugin.
version: 1.0
config_settings:
MyImageURL:
default: http://path.com/images/foo.jpg
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23. Config DirecEve ProperEes
• Registry properEes:
– path
– handler
– alias
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24. Developing for Movable Type in 2 Days
• Day 1: The Basics
– Plugin Structure
– The Registry
– ConfiguraEon DirecEves
➡ Template Tags
– Objects
– Callbacks
• Day 2: Building User Interfaces
– Menus
– New ApplicaEon Screens
– Dialogs
– LisEng Screens
24
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25. Adding a Template Tag
• What is a template tag?
• Where are template tags used?
• What are the various types of template tags?
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26. Adding a Template Tag ‐ config.yaml
name: Good for Nothing Plugin for Movable Type
id: Good4Nothing
key: Good4Nothing
author_link: http://www.yourwebsite.com/
author_name: Your Name Here
description: This plugin is an example plugin.
version: 1.0
config_settings:
MyImageURL:
default: http://path.com/images/foo.jpg
tags:
function:
MyImageURL: $Good4Nothing::Good4Nothing::Plugin::tag
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27. Adding a Template Tag ‐ Handler
# Good for Nothing Plugin for Movable Type
# Author: Your Name Here, your.email@address.com
# Copyright (C) 2008 Your Name Here
# This file is licensed under the Artistic License,
# or the same terms as Perl itself.
package Good4Nothing::Plugin;
use strict;
sub tag {
my ($ctx) = @_;
my $cfg = $ctx->{config};
return $cfg->MyImageURL;
}
1; # Every module must return true
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28. More about Template Tags
• Types of Tags
– funcEon
– block
– modifiers
• CondiEonal Tags
• Loops
• Template Context
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29. More about Template Tags
tags:
function:
'SaySomething': $Example::Example::Plugin::SaySomething
'SayWhatever': $Example::Example::Plugin::SayWhatever
block:
'LoopTenTimes': $Example::Example::Plugin::LoopTenTimes
'IfOdd?': $Example::Example::Plugin::IfOdd
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30. More about Template Tags
# Example: <mt:SaySomething>
sub SaySomething {
my ($ctx, $args) = @_;
return quot;Somethingquot;quot;;
}
# Example: <mt:SayWhatever say=”Hello”>
sub SayWhatever {
my ($ctx, $args) = @_;
# What the person passed in through the
# argument 'say'
my $input = $args->{'say'};
return $input;
}
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31. More about Template Tags
# Example: <mt:LoopTenTimes>...</mt:LoopTenTimes>
sub LoopTenTimes {
my ($ctx, $args, $cond) = @_;
my $out = quot;quot;;
my $builder = $ctx->stash('builder');
my $tokens = $ctx->stash('tokens');
for (my $i = 1; $i <= 10; $i++) {
$ctx->stash(quot;current_loop_numberquot;,$i);
$out .= quot;$i * quot; . $builder->build($ctx,$tokens,$cond);
}
return $out;
}
# Example: <mt:IfOdd>do this</mt:IfOdd>
sub IfOdd {
my ($ctx, $args, $cond) = @_;
my $num = $ctx->stash('current_loop_number');
if ($num % 2 == 0) {
return 0;
} else {
return 1;
}
}
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32. Adding a Tag Modifier
• What is a tag modifier?
• Example modifiers:
– <mt:block capitalize=“1”>abc</block>
– <mt:block ltrim=“1”> foo</mt:block>
– <mt:block regex_replace=“/foo/gi”,”bar”>
foo
</mt:block>
– <mt:block count_words=“1”>Hello World</mt:block>
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33. Adding a Template Tag ‐ config.yaml
name: Good for Nothing Plugin for Movable Type
id: Good4Nothing
key: Good4Nothing
author_link: http://www.yourwebsite.com/
author_name: Your Name Here
description: This plugin is an example plugin.
version: 1.0
config_settings:
MyImageURL:
default: http://path.com/images/foo.jpg
tags:
modifier:
lolcats: $Good4Nothing::Good4Nothing::Plugin::lolcats
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34. Adding a Modifier ‐ Handler
# Good for Nothing Plugin for Movable Type
# Author: Your Name Here, your.email@address.com
# Copyright (C) 2008 Your Name Here
# This file is licensed under the Artistic License,
# or the same terms as Perl itself.
package Good4Nothing::Plugin;
use strict;
sub lolcats {
my ($str, $val, $ctx) = @_;
return quot;CAN I HAZ “. uc($str);
}
1; # Every module must return true
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35. Developing for Movable Type in 2 Days
• Day 1: The Basics
– Plugin Structure
– The Registry
– ConfiguraEon DirecEves
– Template Tags
➡ Objects
– Callbacks
• Day 2: Building User Interfaces
– Menus
– New ApplicaEon Screens
– Dialogs
– LisEng Screens
35
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36. Objects and Data Persistence
• An overview of Movable Type Objects
– MT::Entry
– MT::Comment
– Etc.
• Before and afer a record is modified in the
Movable Type database, an event is fired.
• Plugins can register callbacks for those events.
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37. About MT Objects
• Movable Type’s Data AbstracEon Layer
– Data::ObjectDriver
– MT::ObjectDriver
– MT::Object
• Memcached Support
• Event PropagaEon
• Gegers/Segers
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38. InteracEng with MT::Objects
• MT::MyObject‐>new()
• $obj‐>save()
• MT::MyObject‐>load($terms, $arguments)
• MT::MyObject‐>load_iter($terms, $arguments)
• $obj‐>remove($terms, $arguments)
• MT::MyObject‐>remove_all
• MT::MyObject‐>count($terms)
• MT::MyObject‐>exists($terms)
• $obj‐>clone()
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39. new() and save()
my $foo = MT::Foo->new;
$foo->first_name(’Byrne');
$foo->last_name(‘Reese’);
$foo->save()
or die quot;Saving foo failed: quot;, $foo->errstr;
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40. load()
my @objects = MT::Foo->load(
{
title => quot;Hello Worldquot;,
foo => quot;barquot;,
}, {
sort => 'created_on',
direction => 'ascend',
}
);
foreach my $obj (@objects) {
print $obj->baz();
# do something
}
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41. load_iter()
my $iter = MT::Foo->load_iter(
{
title => quot;Hello Worldquot;,
foo => quot;barquot;,
}, {
sort => 'created_on',
direction => 'ascend',
}
);
while (my $obj = $iter->()) {
print $obj->baz();
# do something
}
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42. load and load_iter OpEons
• sort
• direcEon
• limit
• lastn
• offset
• start_val
• range
• range_incl
• join
• unique
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43. CreaEng Your Own Object
• Schema definiEon
• Registering database indexes
• Record audiEng
• Primary keys
• Meta Data
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44. MT::MyObject
package Example::MyObject;
use strict;
use base qw( MT::Object );
__PACKAGE__->install_properties({
column_defs => {
'id' => 'integer not null auto_increment',
'blog_id' => 'integer',
'some_property' => 'string(100) not null',
},
audit => 1,
indexes => {
id => 1,
},
datasource => 'myplugin_myobject',
primary_key => 'id',
});
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45. MT::Object Database Data Types
• string
• integer
• boolean
• smallint
• dateEme
• blob
• text
• float
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46. Extending ExisEng Objects
• Extending exisEng objects
• schema_version registry property
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47. Extending ExisEng Objects
name: Example Plugin for Movable Type
id: Example
key: Example
description: This plugin is an example plugin
version: 1.0
schema_version: 2
object_types:
entry:
is_featured: smallint
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48. Extending ExisEng Objects
• Which then let’s you do this:
use MT::Entry;
my $entry = MT::Entry->load($id);
$entry->is_featured(1);
$entry->save;
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49. Developing for Movable Type in 2 Days
• Day 1: The Basics
– Plugin Structure
– The Registry
– ConfiguraEon DirecEves
– Template Tags
– Objects
➡ Callbacks
• Day 2: Building User Interfaces
– Menus
– New ApplicaEon Screens
– Dialogs
– LisEng Screens
49
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50. Movable Type Callbacks
• Nomenclature:
– Event, Callback, Fire, Listening
• Event Types
– Object Level
– ApplicaEon Level
– TransformaEon
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51. Object‐Level Callbacks
• Events:
– MT::ObjectName::pre_save
– MT::ObjectName::post_save
– MT::ObjectName::pre_load
– MT::ObjectName::post_load
– MT::ObjectName::pre_remove
– MT::ObjectName::pre_remove_all
– MT::ObjectName::post_remove_all
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52. Adding a Callback ‐ config.yaml
name: Good for Nothing Plugin for Movable Type
id: Good4Nothing
key: Good4Nothing
author_link: http://www.yourwebsite.com/
author_name: Your Name Here
description: This plugin is an example plugin.
version: 1.0
callbacks:
MT::Entry::pre_save: $Example::Example::Plugin::pre_save
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53. Adding a Callback ‐ Handler
package Example::Plugin;
use strict;
sub pre_save {
my ($cb, $obj) = @_;
# $cb - holds a reference to the callback object
# $obj - holds a reference to the object about
# to be saved
# do your thing
if ($error) {
return $cb->error(“Error Message”);
}
}
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54. Exercise: Add a Callback
• Your Mission: Add a record to the Movable
Type AcEvity Log, just afer an entry is saved.
• About Logging:
MT->log({
message => quot;DemoPlugin: an object was saved.quot;,
class => 'system',
level => MT::Log::INFO() });
});
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55. End Day 1
Byrne Reese
byrne@sixapart.com
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