NAME

Catmandu - a data toolkit

SYNOPSIS

# From the command line

# Convert data from one format to another
$ catmandu convert JSON to CSV  < data.json
$ catmandu convert CSV  to YAML < data.csv
$ catmandu convert MARC to YAML < data.mrc

# Fix data, add, delete, change fields
$ catmandu convert JSON --fix 'move_field(title,my_title)' < data.json
$ catmandu convert JSON --fix all_my_fixes.txt < data.json
# Use a moustache preprocessor on the fix script
$ catmandu convert JSON --fix all_my_fixes.txt --var opt1=foo --var opt2=bar < data.json

# Import data into a database
# Requires: Catmandu::MongoDB and Catmandu::ElasticSearch
$ catmandu import YAML to MongoDB --database_name bibliography < data.yml
$ catmandu import CSV to ElasticSearch --index_name mystuff < data.csv

# Export data from a database
# Requires: Catmandu::MongoDB and Catmandu::ElasticSearch
$ catmandu export MongoDB --database_name bibliography to YAML > data.yml
$ catmandu export ElasticSearch --index_name mystuff to CSV > data.csv

# Copy data from one store to another
$ catmandu copy MongoDB --database_name mydb to ElasticSearch --index_name mydb

# Show the contents of catmandu.yml
$ catmandu config

# Count items in a store
$ catmandu count test1

# Delete items from store
$ catmandu delete test1 --query 'title:"My Rabbit"'

# run a fix script
$ catmandu run myfixes.fix

# or, create an executable fix script
$ cat myfixes.fix
#!/usr/local/bin/catmandu run
do importer(OAI,url:"http://biblio.ugent.be/oai")
    retain(_id)
end
$ chmod 755 myfixes.fix
$ ./myfixes.fix

# From Perl
use Catmandu;

# If you have Catmandu::OAI and Catmandu::MongoDB installed
my $importer = Catmandu->importer('OAI',url => 'https://biblio.ugent.be/oai')
my $store    = Catmandu->store('MongoDB',database_name => 'test');

# Import all the OAI records into MongoDB
$store->add_many($importer);

# Export all the MongoDB records to YAML and apply some fixes
# myfixes.txt:
#   upcase(title.*)
#   remove_field(_metadata)
#   join_field(creator,'; ')
#   join_field(subject,'-- ')
my $fixer    = Catmandu->fixer('myfixes.txt');
my $exporter = Catmandu->exporter('YAML');

$exporter->add_many( $fixer->fix($store) );
$exporter->commit;

DESCRIPTION

Catmandu provides a command line client and a Perl API to ease the export (E) transformation (T) and loading (L) of data into databases or data file, ETL in short.

Most of the daily work processing structured data can be done on the command line executing the catmandu command. With our catmandu command ETL processing is available in a Perl context. Catmandu is different from other ETL tools by its focus on command line processing with much support for dataformats available in (academic) libraries: MARC, MODS, OAI and SRU. But, also generic formats such as JSON, YAML, CVS, Excel, XML, RDF, Atom are supported.

Read :

• Catmandu::Introduction for a primer on the command line capabilities of Catmandu.

• Catmandu::Importer for the basics of importing

• Catmandu::Fix for the basics of transformations

• Catmandu::Exporter for the basics of exporting

• Catmandu::Store for the basics of storing information

• Or, visit our website at http://librecat.org/ and our blog https://librecatproject.wordpress.com/ for many tutorials

The documentation below describes the methods available when including Catmandu as part of a Perl script. For an overview of the command line tool itself read the documentation on catmandu.

USE

To include Catmandu in a Perl script it should be loaded with a use command:

use Catmandu;

By default no methods are imported into the Perl context. To import all or some Catmandu methods, provide them as a list to the use command:

use Catmandu -all;
use Catmandu qw(config store exporter);

Catmandu can load configuration options for exports, importers, fixers via configuration files (see the CONFIG section below). When adding the --load option (optionally with a path) to the use command, these configuration files will be loaded at the start of your script.

use Catmandu -load;
use Catmandu --load => ['/my/config/directory'];

# or use all the options
use Catmandu -all -load => [qw(/config/path' '/another/config/path)];

CLASS METHODS

log

Return the current Log::Any logger.

use Catmandu;
use Log::Any::Adapter;
use Log::Log4perl;

Log::Any::Adapter->set('Log4perl'); # requires Log::Any::Adapter::Log4perl
Log::Log4perl::init('./log4perl.conf');

my $logger = Catmandu->log;
$logger->info("Starting main program");

with log4perl.conf like:

# Send a copy of all logging messages to STDERR
log4perl.rootLogger=DEBUG,STDERR

# Logging specific for your main program
log4perl.category.myprog=INFO,STDERR

# Logging specific for on part of Catmandu
log4perl.category.Catmandu::Fix=DEBUG,STDERR

# Where to send the STDERR output
log4perl.appender.STDERR=Log::Log4perl::Appender::Screen
log4perl.appender.STDERR.stderr=1
log4perl.appender.STDERR.utf8=1

log4perl.appender.STDERR.layout=PatternLayout
log4perl.appender.STDERR.layout.ConversionPattern=%d [%P] - %p %l time=%r : %m%n

default_load_path(['/default/path'])

Returns the default location where Catmandu looks for configuration and lib when called with no argument. Sets the default location if a path is given. The default load path is the script directory or it's parent if the script directory is bin.

load

Load all the configuration options in the catmandu.yml configuration file. See CONFIG below for extended examples of configuration options.

load('/path', '/another/path')

Load all the configuration options stored at alternative paths.

A load path ':up' will search upwards from your program for configuration.

See CONFIG below for extended examples of configuration options.

roots

Returns an ARRAYREF of paths where configuration was found. Note that this list is empty before load.

root

Returns the first path where configuration was found. Note that this is undef before load.

config

Returns the current configuration as a HASHREF.

config($config)

Set a new configuration and reload the environment.

default_store

Return the name of the default store.

store([NAME])

Return an instance of Catmandu::Store. The NAME is a name of a Catmandu::Store or the name of a store configured in a catmandu.yml configuration file. When no NAME is given, the 'default' store in the configuration file will be used.

E.g. if the configuration file 'catmandu.yml' contains:

store:
 default:
  package: ElasticSearch
  options:
    index_name: blog
 test:
  package: Mock

then in your program:

# This will use ElasticSearch
my $store = Catmandu->store('ElasticSearch', index_name => 'blog');

# or because we have a 'default' set in the configuration file

my $store = Catmandu->store('default');

# or because 'default' will be used when no name was provided

my $store = Catmandu->store;

# This will use Mock
my $store = Catmandu->store('test');

Configuration settings can be overwritten by the store command:

my $store2 = Catmandu->store('default', index_name => 'test2');

default_fixer

Return the name of the default fixer.

fixer(NAME)

fixer(FIX,FIX)

fixer([FIX])

Return an instance of Catmandu::Fix. NAME can be the name of a fixer section in a catmandu.yml file. Or, one or more Catmandu::Fix-es can be provided inline.

E.g. if the configuration file 'catmandu.yml' contains:

fixer:
 default:
   - do_this()
   - do_that()

then in your program al these lines below will create the same fixer:

my $fixer = Catmandu->fixer('do_this()', 'do_that()');
my $fixer = Catmandu->fixer(['do_this()', 'do_that()']);
my $fixer = Catmandu->fixer('default');
my $fixer = Catmandu->fixer(); # The default name is 'default'

FIX-es can be also written to a Fix script. E.g. if myfixes.txt contains:

do_this()
do_that()

then the above code will even be equivalent to:

my $fixer = Catmandu->fixer('myfixes.txt');

default_importer

Return the name of the default importer.

default_importer_package

Return the name of the default importer package if no package name is given in the config or as a param.

importer(NAME)

Return an instance of Catmandu::Importer. The NAME is a name of a Catmandu::Importer or the name of a importer configured in a catmandu.yml configuration file. When no NAME is given, the 'default' importer in the configuration file will be used.

E.g. if the configuration file 'catmandu.yml' contains:

importer:
  default:
    package: OAI
    options:
      url: http://www.instute.org/oai/

then in your program all these lines will be equivalent:

my $importer = Catmandu->importer('OAI', url => 'http://www.instute.org/oai/');
my $importer = Catmandu->importer('default');
my $importer = Catmandu->importer(); # The default name is 'default'

Configuration settings can be overwritten by the importer command:

my $importer2 = Catmandu->importer('default', url => 'http://other.institute.org');

default_exporter

Return the name of the default exporter.

default_exporter_package

Return the name of the default exporter package if no package name is given in the config or as a param.

exporter([NAME])

Return an instance of Catmandu::Exporter with name NAME (or the default when no name is given). The NAME is set in the configuration file (see 'importer').

export($data,[NAME])

Export data using a default or named exporter or exporter instance.

Catmandu->export({ foo=>'bar'});

my $importer = Catmandu::Importer::Mock->new;
Catmandu->export($importer, 'YAML', file => '/my/file');
Catmandu->export($importer, 'my_exporter');
Catmandu->export($importer, 'my_exporter', exporter_option => '...' , ...);
Catmantu->export($importer, Catmandu::Exporter::YAML->new);

export_to_string

Export data using a default or named exporter to a string.

my $importer = Catmandu::Importer::Mock->new;
my $yaml = Catmandu->export_to_string($importer, 'YAML');
# is the same as
my $yaml = "";
Catmandu->export($importer, 'YAML', file => \$yaml);

import_from_string

Import data from a string using a default or named importer. Return value should be an array of hashes.

my $json = qq([{"name":"Nicolas"}]);
{
    my $record = Catmandu->import_from_string( $json, "JSON" );
}
# is the same as
{
    my $record = Catmandu->importer('JSON', file => \$json)->to_array()
}

define_importer

Configure a new named importer.

Catmandu->define_importer(books => CSV => (fields => 'title,author,publisher'));
Catmandu->importer(books => (file => 'mybooks.csv'))->each(sub {
    my $book = shift;
    say $book->{title};
});

# this is equivalent to

Catmandu->config->{importer}{books} = {
    package => 'CSV',
    options => {
        fields => 'title,author,publisher',
    },
}

define_exporter

Configure a new named exporter.

Catmandu->define_exporter('books', 'CSV', fix => 'capitalize(title)');
my $csv = Catmandu->export_to_string({title => 'nexus'}, 'books');

# this is equivalent to

Catmandu->config->{exporter}{books} = {
    package => 'CSV',
    options => {
        fix => 'capitalize(title)',
    },
}

define_store

Configure a new named store.

Catmandu->define_store(mydb => MongoDB => (database_name => 'mydb'));
Catmandu->store->bag('books')->get(1234);

# this is equivalent to

Catmandu->config->{store}{mydb} = {
    package => 'MongoDB',
    options => {
        database_name => 'mydb',
    },
}

define_fixer

Configure a new named fixer.

Catmandu->define_fixer('cleanup', [
    'trim(title)',
    'capitalize(title)',
    'remove_field(junk)',
    # ...
]);
Catmandu->fixer('cleanup')->fix($record);

EXPORTS

config

Same as Catmandu->config.

store

Same as Catmandu->store.

importer

Same as Catmandu->importer.

exporter

Same as Catmandu->exporter.

export

Same as Catmandu->export.

export_to_string

Same as Catmandu->export_to_string.

import_from_string

Same as Catmandu->import_from_string.

fixer

Same as Catmandu->fixer.

log

Same as Catmandu->log.

-all/:all

Import everything.

-load/:load

use Catmandu -load;
use Catmandu -load => [];
# is the same as
Catmandu->load;

use Catmandu -load => ['/config/path'];
# is the same as
Catmandu->load('/config/path');

CONFIG

Catmandu configuration options can be stored in files in the root directory of your programming project. The file can be YAML, JSON or Perl and is called catmandu.yml, catmandu.json or catmandu.pl. In this file you can set the default Catmandu stores and exporters to be used. Here is an example of a catmandu.yml file:

store:
  default:
    package: ElasticSearch
    options:
      index_name: myrepository

exporter:
  default:
    package: YAML

Split config

For large configs it's more convenient to split the config into several files. You can do so by having multiple config files starting with catmandu*.

catmandu.general.yml
catmandu.db.yml
...

Split config files are processed and merged by Config::Onion.

Deeply nested config structures

Config files can indicate a path under which their keys will be nested. This makes your configuration more readable by keeping indentation to a minimum.

A config file containing

_prefix:
    foo:
        bar:
baz: 1

will be loaded as

foo:
  bar:
    baz: 1

See Config::Onion for more information on how this works.

SEE ALSO

documentation

http://librecat.org/Catmandu/

command line client

catmandu

core modules

Catmandu::Importer Catmandu::Exporter, Catmandu::Store, Catmandu::Fix, Catmandu::Iterable

extended features

Catmandu::Validator

AUTHOR

Nicolas Steenlant, <nicolas.steenlant at ugent.be>

CONTRIBUTORS

Magnus Enger, magnus at enger.priv.no

Nicolas Franck, nicolas.franck at ugent.be

Patrick Hochstenbach, patrick.hochstenbach at ugent.be

Vitali Peil, vitali.peil at uni-bielefeld.de

Christian Pietsch, christian.pietsch at uni-bielefeld.de

Dave Sherohman, dave.sherohman at ub.lu.se

Jakob Voss, nichtich at cpan.org

Snorri Briem, snorri.briem at ub.lu.se

Johann Rolschewski, jorol at cpan.org

Pieter De Praetere, pieter.de.praetere at helptux.be

Doug Bell

Upsana, me at upasana.me

Stefan Weil

Tom Hukins

QUESTIONS, ISSUES & BUG REPORTS

For any questions on the use of our modules please join our mailing list at:

librecat-dev@lists.uni-bielefeld.de

or send in your bug reports or feature requests to our issue tracker at:

https://github.com/LibreCat/Catmandu/issues

LICENSE AND COPYRIGHT

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.

cpanm Catmandu

perl -MCPAN -e shell
install Catmandu