bionic (3) Catmandu::Introduction.3pm.gz

NAME

       Catmandu::Introduction - An Introduction to Catmandu data processing toolkit

Introduction

       Catmandu is a data processing toolkit developed as part of the LibreCat <http://librecat.org> project.
       Catmandu provides the command line client catmandu and a suite of tools to ease the import, storage,
       retrieval, export and transformation of data. For instance, to transform a CSV file into JSON use the
       command:

           $ catmandu convert JSON to CSV < data.json

       Or, to store a YAML file into an ElasticSearch database type (requires Catmandu::ElasticSearch):

           $ catmandu import YAML to ElasticSearch --index_name demo < test.yml

       To export all the data from an Solr search engine into JSON type (requires Catmandu::Solr):

           $ catmandu export Solr --url http://localhost:8983/solr to JSON

       With Catmandu one can import OAI-PMH records in your application (requires Catmandu::OAI):

           $ catmandu convert OAI --url http://biblio.ugent.be/oai --set allFtxt

       and export records into formats such as JSON, YAML, CSV, XLS, RDF and many more.

       Catmandu also provides a small scripting language to manipulate data, extract parts of your dataset and
       transform records. For instance, rename fields  with the 'move_field' Fix command:

           $ catmandu convert JSON --fix 'move_field(title,my_title)' < data.json

       In the example above, we renamed all the 'title' fields in the dataset into the 'my_title' field.

       One can also work on deeply nested data. E.g. create a deeply nested data structure with the 'move_field'
       Fix command:

           $ catmandu convert JSON --fix 'move_field(title,my.deeply.nested.title)' < data.json

       In this example we moved the field 'title' into the field 'my', which contains a (sub)field 'deeply',
       which contains a (sub)field 'nested'.

       Catmandu was originally created by librarians for librarians. We process a lot of metadata especially
       library metadata in formats such as MARC, MAB2 and MODS. With the following command we can extract data
       from a marc record and to store it into the title field (requires Catmandu::MARC):

           $ catmandu convert MARC --fix 'marc_map(245,title)' < data.mrc

       Or, in case only the 245a subfield is needed write:

           $ catmandu convert MARC --fix 'marc_map(245a,title)' < data.mrc

       When processing data a lot of Fix commands could be required. It wouldn't be very practical to type them
       all on the command line. By creating a Fix script which contains all the fix commands complicated data
       transformations can be created. For instance, if the file "myfixes.txt" contains:

            marc_map(245a,title)
            marc_map(100a,author.$append)
            marc_map(700a,author.$append)
            marc_map(020a,isbn)
            replace_all(isbn,'[^0-9-]+','')

       then they can be executed on a MARC file using this command:

           $ catmandu convert MARC --fix myfixes.txt < data.mrc

       Fixes can also be turned into executable scripts by adding a bash 'shebang' line at the top. E.g.  to
       harvest records from an OAI repository write this fix file:

            #!/usr/bin/env catmandu run
            do importer(OAI,url:"http://lib.ugent.be/oai")
               add_to_exporter(.,JSON)
            end

       Run this (on Linux) by setting the executable bit:

            $ chmod 755 myfix.fix
            $ ./myfix.fix

       To experiment with the Fix language you can also run the catmandu Fix interpreter in an interactive mode:

            $ catmandu run
            Catmandu 0.95 interactive mode
            Type: \h for the command history
            fix > add_field(hello,world)
            ---
            hello: world
            ...
            fix >

       Catmandu contains many powerful fixes. Visit <http://librecat.org/Catmandu/#fixes-cheat-sheet> to get an
       overview what is possible.

Documentation

       For more information read our documentation pages <http://librecat.org/Catmandu/> and blog
       <https://librecatproject.wordpress.com/> for a complete introduction and update into all Catmandu
       features.

       In the winter of 2014 an Advent calendar tutorial was created to provide a day by day introduction into
       the UNIX command line and Catmandu:

       <https://librecatproject.wordpress.com/2014/12/01/day-1-getting-catmandu/>

       If you need extra training, our developers regulary host workshops at library conferences and events:
       <http://librecat.org/events.html>

Installation

       There are several ways to get a working version of Catmandu on your computer.  For a quick and demo
       installation visit our blog <https://librecatproject.wordpress.com/get-catmandu/> where a VirtualBox
       image is available containing all the Catmandu modules, including ElasticSearch and MongoDB.

       On our website <http://librecat.org/Catmandu/#installation> we provide installation instructions for:

       Debian
       Ubuntu Server
       CentOS
       openSUSE
       OpenBSD
       Windows

       and even a generic installation using Docker <https://www.docker.com/>:
       <https://hub.docker.com/r/librecat/catmandu/>.

Open Source

       Catmandu software published at https://github.com/LibreCat/Catmandu is free software without warranty,
       liabilities or support; you can redistribute it and/or modify it under the terms of the GNU General
       Public License as published by the Free Software Foundation; either version 2 or any later version. Every
       contributor is free to state her/his copyright.

Developers & Support

       Catmandu has a very active international developer community. We welcome all feedback, bug reports and
       feature enhancement.

       Join our mailing list to receive more information:  "librecat-dev@librecat.org"

       Are a developer and want to contribute to the project? Feel free to submit pull requests or create new
       Catmandu packages!

Kudos

       Catmandu is created in a cooperation with many developers world wide. Without them this project isn't
       possible.  We would like to thank our core maintainer: Nicolas Steenlant and all contributors: Christian
       Pietsch , Dave Sherohman , Friedrich Summann , Jakob Voss , Johann Rolschewski  , Jorgen Eriksson  ,
       Magnus Enger , Maria Hedberg , Mathias Loesch , Najko Jahn , Nicolas Franck , Patrick Hochstenbach ,
       Petra Kohorst  , Snorri Briem , Upasana Shukla and Vitali Peil

SEE ALSO

       Catmandu

       <http://librecat.org/>