NAME
Catalyst::Plugin::AutoCRUD - Instant AJAX web front-end for DBIx::Class
VERSION
version 2.123270
PURPOSE
You have a database, and wish to have a basic web interface supporting
Create, Retrieve, Update, Delete and Search, with little effort. This
module is able to create such interfaces on the fly. They are a bit
whizzy and all Web 2.0-ish.
* See the demo at: <http://demo.autocrud.pl/>
SYNOPSIS
If you already have a Catalyst app with DBIx::Class models configured:
use Catalyst qw(AutoCRUD); # <-- add the plugin name here in MyApp.pm
Now load your app in a web browser, but add "/autocrud" to the URL path.
Alternatively, to connect to an external database if you have the
DBIX::Class schema available, use the "ConfigLoader" plugin with the
following config:
<Model::AutoCRUD::DBIC>
schema_class My::Database::Schema
connect_info dbi:Pg:dbname=mydbname;host=mydbhost.example.com;
connect_info username
connect_info password
<connect_info>
AutoCommit 1
</connect_info>
</Model::AutoCRUD::DBIC>
If you don't have the DBIx::Class schema available, just omit the
"schema_class" option (and have DBIx::Class::Schema::Loader installed).
DESCRIPTION
This module contains an application which will automatically construct a
web interface for a database on the fly. The web interface supports
Create, Retrieve, Update, Delete and Search operations.
The interface is not written to static files on your system, and uses
AJAX to act upon the database without reloading your web page (much like
other Web 2.0 applications, for example Google Mail).
Almost all the information required by the plugin is retrieved from the
DBIx::Class ORM frontend to your database, which it is expected that you
have already set up (although see "USAGE", below). This means that any
change in database schema ought to be reflected immediately in the web
interface after a page refresh.
USAGE
Read Me First
* If you get stuck, read the Troubleshooting documentation.
* DBIx::Class users should read DBIx::Class Tips.
* This plugin provides no user-based access authentication or
authorization. Please take care when deploying, and consider who
will have access. It is possible to restrict the add/update/delete
operations on data. See "TIPS AND TRICKS" for other suggestions.
Scenario 1: Plugin to an existing Catalyst App
This mode is for when you have written your Catalyst application, but
the Views are catering for the users and as an admin you'd like a more
direct, secondary web interface to the database.
package AutoCRUDUser;
use Catalyst qw(AutoCRUD);
__PACKAGE__->setup;
1;
Adding "Catalyst::Plugin::AutoCRUD" as a plugin to your Catalyst
application, as above, causes it to scan your existing Models. If any of
them are built using Catalyst::Model::DBIC::Schema, they are
automatically loaded.
This mode of operation works even if you have more than one database.
You will be offered a Home screen to select the database, and then
another menu to select the table within that.
Remember that the pages available from this plugin will be located under
the "/autocrud" path of your application. Use the "basepath" option if
you want to override this.
Scenario 2: Frontend for an existing "DBIx::Class::Schema" based class
In this mode, "Catalyst::Plugin::AutoCRUD" is running standalone, in a
sense as the Catalyst application itself. Your main application file
looks almost the same as in Scenario 1, except you'll need the
"ConfigLoader" plugin:
package AutoCRUDUser;
use Catalyst qw(ConfigLoader AutoCRUD);
__PACKAGE__->setup;
1;
For the configuration, you need to tell AutoCRUD which package contains
the "DBIx::Class" schema, and also provide database connection
parameters.
<Model::AutoCRUD::DBIC>
schema_class My::Database::Schema
connect_info dbi:Pg:dbname=mydbname;host=mydbhost.example.com;
connect_info username
connect_info password
<connect_info>
AutoCommit 1
</connect_info>
</Model::AutoCRUD::DBIC>
The "Model::AutoCRUD::DBIC" section must look (and be named) exactly
like that above, except you should of course change the "schema_class"
value and the values within "connect_info".
Remember that the pages available from this plugin will be located under
the "/autocrud" path if your application. Use the "basepath" option if
you want to override this.
"DBIx::Class" setup
You will of course need the "DBIx::Class" schema to be created and
installed on your system. The recommended way to do this quickly is to
use the excellent DBIx::Class::Schema::Loader module which connects to
your database and writes "DBIx::Class" Perl modules for it.
Pick a suitable namespace for your schema, which is not related to this
application. For example "DBIC::Database::Foo::Schema" for the "Foo"
database (in the configuration example above we used
"My::Database::Schema"). Then use the following command-line
incantation:
perl -MDBIx::Class::Schema::Loader=make_schema_at,dump_to_dir:. -e \
'make_schema_at("DBIC::Database::Foo::Schema", { debug => 1, naming => 'current' }, \
["dbi:Pg:dbname=foodb;host=mydbhost.example.com","user","pass" ])'
This will create a directory (such as "DBIC") which you need to move
into your Perl Include path (one of the paths shown at the end of "perl
-V").
Scenario 3: Lazy loading a "DBIx::Class" schema
If you're in such a hurry that you can't create the "DBIx::Class"
schema, as shown in the previous section, then
"Catalyst::Plugin::AutoCRUD" is able to do this on the fly, but it will
slow the application's startup just a little.
The application file and configuration are very similar to those in
Scenario two, above, except that you omit the "schema_class"
configuration option because you want AutoCRUD to generate that on the
fly (rather than reading an existing one from disk).
package AutoCRUDUser;
use Catalyst qw(ConfigLoader AutoCRUD);
__PACKAGE__->setup;
1;
<Model::AutoCRUD::DBIC>
connect_info dbi:Pg:dbname=mydbname;host=mydbhost.example.com;
connect_info username
connect_info password
<connect_info>
AutoCommit 1
</connect_info>
</Model::AutoCRUD::DBIC>
When AutoCRUD loads it will connect to the database and use the
DBIx::Class::Schema::Loader module to reverse engineer its schema. To
work properly you'll need the very latest version of that module (at
least 0.05, or the most recent development release from CPAN).
The other drawback to this scenario (other than the slower operation) is
that you have no ability to customize how foreign, related records are
shown. A related record will simply be represented as something
approximating the name of the foreign table, the names of the primary
keys, and associated values (e.g. id(5)).
TIPS AND TRICKS
Displaying Unicode
It is essential that you load the Catalyst::Plugin::Unicode::Encoding
plugin to ensure proper decoding/encoding of incoming request parameters
and the outgoing body response respectively. This is done in your
"MyApp.pm":
use Catalyst qw/ -Debug ConfigLoader Unicode::Encoding AutoCRUD /;
Additionally, when connecting to the database, add a flag to the
connection parameters, specific to your database engine, that enables
Unicode. See the following link for more details:
* <https://metacpan.org/module/DBIx::Class::Manual::Cookbook#Using-Uni
code>
Representing related records
When the web interface wants to display a column which references
another table, you can make things look much better by adding a custom
render method to your "DBIx::Class" Result Classes (i.e. the class files
for each table).
First, the plugin will look for a method called "display_name" and use
that. Here is an example which could be added to your Result Class files
below the line which reads "DO NOT MODIFY THIS OR ANYTHING ABOVE", and
in this case returns the data from the "title" column:
sub display_name {
my $self = shift;
return $self->title || '';
}
Failing the existence of a "display_name" method, the plugin attempts to
stringify the row object. Using stringification is not recommended,
although some people like it. Here is an example of a stringification
handler:
use overload '""' => sub {
my $self = shift;
return $self->title || '';
}, fallback => 1;
If all else fails the plugin prints the best hint it can to describe the
foreign row. This is something approximating the name of the foreign
table, the names of the primary keys, and associated values. It's better
than stringifying the object the way Perl does, anyway.
Textfields and Textareas
When the plugin creates a web form for adding or editing, it has to
choose whether to show a Textfield or Textarea for text-type fields. If
you have set a "size" option in add_columns() within the Schema, and
this is less than or equal to 40, a Textfield is used. Otherwise, if the
"size" option is larger than 40 or not set, then an auto-expanding,
scrollable Textarea is used.
Column names with spaces
The plugin will handle most tricky names, but you should remember to
pass some required extra quoting hints to DBIx::Class when it makes a
connection to your database:
# most databases:
{ quote_char => q{`}, name_sep => q{.} }
# SQL Server:
{ quote_char => [qw/[ ]/], name_sep => q{.} }
For more information see the DBIx::Class::Storage::DBI manual page or
ask on the DBIx::Class mail list.
Database IO filters
Buried within one of the modules in this application are some filters
which are applied to data of certain types as it enters or leaves the
database. If you find a particular data type is not being rendered
correctly, please drop the author a line at the email address below,
explaining what you'd like to see instead.
Relocating AutoCRUD to another URL path
If you want to use this application as a plugin with another Catalyst
system, it should work fine, but you probably want to serve pages under
a different path on your web site. To that end, the plugin by default
places its pages under a path part of ".../autocrud/". You can change
this by adding the following option to your configuration file:
<Plugin::AutoCRUD>
basepath admin
</Plugin::AutoCRUD>
In the above example, the path ".../admin/" will contain the AutoCRUD
application, and all generated links in AutoCRUD will also make use of
that path. Remember this is added to the "base" of your Cataylst
application which, depending on your web server configuration, might
also have a leading path.
To have the links based at the root of your application (which was the
default behaviour of "CatalystX::ListFramework::Builder", set this
variable to an empty string in your configuration:
<Plugin::AutoCRUD>
basepath ""
</Plugin::AutoCRUD>
Using your own ExtJS libraries
The plugin will use copies of the ExtJS libraries hosted in the CacheFly
content delivery network out there on the Internet. Under some
circumstances you'll want to use your own hosted copy, for instance if
you are serving HTTPS (because browsers will warn about mixed HTTP and
HTTPS content).
In which case, you'll need to download the ExtJS Javascript Library
(version 2.2+ recommended), from this web page:
<http://www.sencha.com/products/extjs/download/>.
Install it to your web server in a location that it is able to serve as
static content. Make a note of the path used in a URL to retrieve this
content, as it will be needed in the application configuration file,
like so:
<Plugin::AutoCRUD>
extjs2 /static/javascript/extjs-2
</Plugin::AutoCRUD>
Use the "extjs2" option as shown above to specify the URL path to the
libraries. This will be used in the templates in some way like this:
<script type="text/javascript" src="[% c.config.extjs2 %]/ext-all.js" />
Changing the HTML Character Set
The default HTML "charset" used by this module is "utf-8". If you wish
to override this, then set the "html_charset" parameter, as below:
<Plugin::AutoCRUD>
html_charset iso-8859-1
</Plugin::AutoCRUD>
Simple read-only non-JavaScript Frontend
All table views will default to the full-featured ExtJS based frontend.
If you would prefer to see a simple read-only non-JavaScript interface,
then append "/browse" to your URL.
This simpler frontend uses HTTP GET only, supports paging and sorting,
and will obey any column filtering and renaming as set in your "SITES
CONFIGURATION" file.
Overriding built-in Templates
The whole site is built from Perl Template Toolkit templates, and it is
possible to override these shipped templates with your own files. This
goes for both general files (CSS, top-level TT wrapper) as well as the
site files mentioned in the next section.
To add these override paths, include the following directive in your
configuration file:
<Plugin::AutoCRUD>
tt_path /path/to/my/local/templates
</Plugin::AutoCRUD>
This "tt_path" directive can be included multiple times to set a list of
override paths, which will be processed in the order given.
Within the specified directory you should mirror the file structure
where the overridden templates have come from, including the frontend
name. For example:
extjs2
extjs2/wrapper
extjs2/wrapper/footer.tt
skinny
skinny/wrapper
skinny/wrapper/footer.tt
If you want to override any of the CSS used in the app, copy the
"head.tt" template from whichever "site" you are using, edit, and
install in a local "tt_path" set with this directive.
SITES CONFIGURATION
It's possible to have multiple views of the source data, tailored in
various ways. For example you might choose to hide some tables, or
columns within tables, rename headings of columns, or disable updates or
deletes.
This is all achieved through the "sites" configuration. Altering the
default site simply allows for control of column naming, hiding, etc.
Creating a new site allows you to present alternate configurations of
the same source data.
Altering the Default Site
When using this plugin out of the box you're already running within the
default site, which unsurprisingly is called "default". To override
settings in this, create the following configuration stub, and fill it
in with any of the options listed below:
<Plugin::AutoCRUD>
<sites>
<default>
# override settings here
</default>
</sites>
</Plugin::AutoCRUD>
Configuration Options for Sites
In general, when you apply a setting to something at a higher level
(say, a database), it *percolates* down to the child sections (i.e. the
tables). For example, setting "delete_allowed no" on a database will
prevent records from any table within that from being deleted.
Some of the options are *global* for a site, others apply to the
database or table within it. To specify an option for one or the other,
use the database and table names *as they appear in the URL path*:
<Plugin::AutoCRUD>
<sites>
<default>
# global settings for the site, here
<mydb>
# override settings here
<sometable>
# and/or override settings here
</sometable
</mydb>
</default>
</sites>
</Plugin::AutoCRUD>
Options
update_allowed [ yes* | no ]
This can be applied to either a database or a table; if applied to a
database it percolates to all the tables, unless the table has a
different setting.
The default is to allow updates to be made to existing records. Set
this to a value of "no" to prevent this operation from being
permitted. Widgets will also be removed from the user interface so
as not to confuse users.
<Plugin::AutoCRUD>
<sites>
<default>
update_allowed no
</default>
</sites>
</Plugin::AutoCRUD>
create_allowed [ yes* | no ]
This can be applied to either a database or a table; if applied to a
database it percolates to all the tables, unless the table has a
different setting.
The default is to allow new records to be created. Set this to a
value of "no" to prevent this operation from being allowed. Widgets
will also be removed from the user interface so as not to confuse
users.
<Plugin::AutoCRUD>
<sites>
<default>
create_allowed no
</default>
</sites>
</Plugin::AutoCRUD>
delete_allowed [ yes* | no ]
This can be applied to either a database or a table; if applied to a
database it percolates to all the tables, unless the table has a
different setting.
The default is to allow deletions of records in the tables. Set this
to a value of "no" to prevent deletions from being allowed. Widgets
will also be removed from the user interface so as not to confuse
users.
<Plugin::AutoCRUD>
<sites>
<default>
delete_allowed no
</default>
</sites>
</Plugin::AutoCRUD>
columns \@column_names
This option achieves two purposes. First, you can re-order the set
of columns as they are displayed to the user. Second, by omitting
columns from this list you can hide them from the main table views.
Provide a list of the column names (as the data source knows them)
to this setting. This option must appear at the table level of your
site config hierarchy. In "Config::General" format, this would look
something like:
<Plugin::AutoCRUD>
<sites>
<default>
<mydb>
<thetable>
columns id
columns title
columns length
</thetable>
</mydb>
</default>
</sites>
</Plugin::AutoCRUD>
Any columns existing in the table, but not mentioned there, will not
be displayed in the main table. They'll still appear in the record
edit form, as some fields are required by the database schema so
cannot be hidden. Columns will be displayed in the same order that
you list them in the configuration.
headings { col => title, ... }
You can alter the title given to any column in the user interface,
by providing a hash mapping of column names (as the data source
knows them) to titles you wish displayed to the user. This option
must appear at the table level of your site config hierarchy. In
"Config::General" format, this would look something like:
<Plugin::AutoCRUD>
<sites>
<default>
<mydb>
<thetable>
<headings>
id Key
title Name
length Time
</headings>
</thetable>
</mydb>
</default>
</sites>
</Plugin::AutoCRUD>
Any columns not included in the hash mapping will use the default
title (i.e. what the plugin works out for itself). To hide a column
from view, use the "columns" option, described above.
hidden [ yes | no* ]
If you don't want a database to be offered to the user, or likewise
a particular table, then set this option to "yes". By default, all
databases and tables are shown in the user interface.
<Plugin::AutoCRUD>
<sites>
<default>
<mydb>
<secrettable>
hidden yes
</secrettable>
</mydb>
</default>
</sites>
</Plugin::AutoCRUD>
This can be applied to either a database or table; if applied to a
database it overrides all child tables, even if a table has a
different setting.
frontend [ extjs2 | skinny | ... ]
With this option you can swap out the set of templates used to
generate the web front-end, and completely change its look and feel.
Currently you have two choices: either "extjs2" which is the default
and provides the standard full-featured ExtJS2 frontend, or "skinny"
which is a read-only non-JavaScript alternative supporting listing,
paging and sorting only.
Set the frontend in your site config at its top level. Note that you
cannot set the frontend on a per-database or per-table basis, only
per-site:
<Plugin::AutoCRUD>
<sites>
<default>
frontend skinny
</default>
</sites>
</Plugin::AutoCRUD>
Be aware that setting the frontend to "skinny" does not restrict
create or update access to your database via the AJAX API. For that,
you still should set the *_allowed options listed above, as
required.
Creating a New Site
You can create a new site by adding it to the "sites" section of your
configuration:
<Plugin::AutoCRUD>
<sites>
<mysite>
# local settings here
</mysite>
</sites>
</Plugin::AutoCRUD>
You'll notice that a non-default site is active because the path in your
URLs changes to a more RPC-like verbose form, mentioning the site,
database and table:
from this:
.../autocrud/mydb/thetable # (i.e. site == default)
to this:
.../autocrud/site/mysite/schema/mydb/source/thetable
So let's say you've created a dumbed down site for your users which is
read-only (i.e. "update_allowed no" and "delete_allowed no"), and called
the site "simplesite" in your configuration. You need to give the
following URL to users:
.../autocrud/site/simplesite
You could also then place an access control on this path part in your
web server (e.g. Apache) which is different from the default site
itself.
INSTANT DEMO APPLICATIONS
Automagic Loading
If you want to run an instant demo of this module, with minimal
configuration, then a simple application for that is shipped with this
distribution. For this to work, you must have:
* The very latest version of DBIx::Class::Schema::Loader installed on
your system (at least 0.05, or the most recent release from CPAN).
* SQLite3 and the accompanying DBD module, if you want to use the
shipped demo database.
Go to the "examples/sql/" directory of this distribution and run the
"bootstrap_sqlite.pl" perl script. This will create an SQLite file.
Now change to the "examples/demo/" directory and start the demo
application like so:
demo> perl ./server.pl
Visit "http://localhost:3000" in your browser as instructed at the end
of the output from this command.
To use your own database rather than the SQLite demo, edit
"examples/demo/demo.conf" so that it contains the correct "dsn",
username, and password for your database. Upon restarting the
application you should see your own data source instead.
Row Display Names
An alternate application exists which demonstrates use of the
"display_name" method on a DBIx::Class Row, to give row entries
"friendly names". Follow all the instructions above but instead run the
following server script:
demo> perl ./server_with_display_name.pl
Other Features
Finally, the kitchen sink of other features supported by this module are
demonstrated in a separate application. This contains many tables, each
of which highlights one or more aspects of a relational database backend
being rendered in AutoCRUD.
Follow all the instructions above, but instead run the following server
script:
demo> perl ./server_other_features.pl
TROUBLESHOOTING
See Catalyst::Plugin::AutoCRUD::Manual::Troubleshooting.
LIMITATIONS
See Catalyst::Plugin::AutoCRUD::Manual::Limitations.
SEE ALSO
CatalystX::CRUD and CatalystX::CRUD:YUI are two distributions which
allow you to create something similar but with full customization, and
the ability to add more features. So, you trade effort for flexibility
and power.
ACKNOWLEDGEMENTS
Without the initial work on "CatalystX::ListFramework" by Andrew Payne
and Peter Edwards this package would not exist. If you are looking for
something like this module but without the dependency on Javascript,
please do check out CatalystX::ListFramework.
AUTHOR
Oliver Gorwits <oliver@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2012 by Oliver Gorwits.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.