NAME

Catmandu::Importer::OAI - Package that imports OAI-PMH feeds

SYNOPSIS

# From the command line

# Harvest records
$ catmandu convert OAI --url http://myrepo.org/oai
$ catmandu convert OAI --url http://myrepo.org/oai --metadataPrefix didl --handler raw

# Harvest repository description
$ catmandu convert OAI --url http://myrepo.org/oai --identify 1

# Harvest identifiers
$ catmandu convert OAI --url http://myrepo.org/oai --listIdentifiers 1

# Harvest sets
$ catmandu convert OAI --url http://myrepo.org/oai --listSets 1

# Harvest metadataFormats
$ catmandu convert OAI --url http://myrepo.org/oai --listMetadataFormats 1

# Harvest one record
$ catmandu convert OAI --url http://myrepo.org/oai --getRecord 1 --identifier oai:myrepo:1234

DESCRIPTION

Catmandu::Importer::OAI is an Catmandu importer to harvest metadata records from an OAI-PMH endpoint.

CONFIGURATION

url

OAI-PMH Base URL.

metadataPrefix

Metadata prefix to specify the metadata format. Set to oai_dc by default.

handler( sub {} | $object | 'NAME' | '+NAME' )

Handler to transform each record from XML DOM (XML::LibXML::Element) into Perl hash.

Handlers can be provided as function reference, an instance of a Perl package that implements 'parse', or by a package NAME. Package names should be prepended by + or prefixed with Catmandu::Importer::OAI::Parser. E.g foobar will create a Catmandu::Importer::OAI::Parser::foobar instance.

By default the handler Catmandu::Importer::OAI::Parser::oai_dc is used for metadataPrefix oai_dc, Catmandu::Importer::OAI::Parser::marcxml for marcxml, Catmandu::Importer::OAI::Parser::mods for mods, and Catmandu::Importer::OAI::Parser::struct for other formats. In addition there is Catmandu::Importer::OAI::Parser::raw to return the XML as it is.

identifier

Option return only results for this particular identifier

set

An optional set for selective harvesting.

from

An optional datetime value (YYYY-MM-DD or YYYY-MM-DDThh:mm:ssZ) as lower bound for datestamp-based selective harvesting.

until

An optional datetime value (YYYY-MM-DD or YYYY-MM-DDThh:mm:ssZ) as upper bound for datestamp-based selective harvesting.

identify

Harvest the repository description instead of all records.

getRecord

Harvest one record instead of all records.

listIdentifiers

Harvest identifiers instead of full records.

listRecords

Harvest full records. Default operation.

listSets

Harvest sets instead of records.

listMetadataFormats

Harvest metadata formats of records

resumptionToken

An optional resumptionToken to start harvesting from.

dry

Don't do any HTTP requests but return URLs that data would be queried from.

strict

Optional validate all parameters first against the OAI 2 spefications before sending it to an OAI server. Default: undef.

xslt

Preprocess XML records with XSLT script(s) given as comma separated list or array reference. Requires Catmandu::XML.

max_retries

When an oai request fails, the importer will retry this number of times. Set to '0' by default.

Internally the exponential backoff algorithm is used for this. This means that after every failed request the importer will choose a random number between 0 and 2^collision (excluded), and wait that number of seconds. So the actual ammount of time before the importer stops can differ:

first retry:
   wait [ 0..2^1 [ seconds
second retry:
   wait [ 0..2^2 [ seconds
third retry:
   wait [ 0..2^3 [ seconds

..

sleep

Sleep a number of seconds between OAI-PMH calls to the endpoint (default 0).

realm

An optional realm value. This value is used when the importer harvests from a repository which is secured with basic authentication through Integrated Windows Authentication (NTLM or Kerberos).

username

An optional username value. This value is used when the importer harvests from a repository which is secured with basic authentication.

password

An optional password value. This value is used when the importer harvests from a repository which is secured with basic authentication.

METHOD

Every Catmandu::Importer is a Catmandu::Iterable all its methods are inherited. The Catmandu::Importer::OAI methods are not idempotent: OAI-PMH feeds can only be read once.

In addition to methods inherited from Catmandu::Iterable, this module provides the following public methods:

handle_record( $dom )

Process an XML DOM as with xslt and handler as configured and return the result.

ENVIRONMENT

If you are connected to the internet via a proxy server you need to set the coordinates to this proxy in your environment:

export http_proxy="http://localhost:8080"

If you are connecting to a HTTPS server and don't want to verify the validity of certificates of the peer you can set the PERL_LWP_SSL_VERIFY_HOSTNAME to false in your environment. This maybe required to connect to broken SSL servers:

export PERL_LWP_SSL_VERIFY_HOSTNAME=0

SEE ALSO

Catmandu , Catmandu::Importer

AUTHOR

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

CONTRIBUTOR

Patrick Hochstenbach, <patrick.hochstenbach at ugent.be>

Jakob Voss, <nichtich at cpan.org>

Nicolas Franck, <nicolas.franck at ugent.be>

LICENSE AND COPYRIGHT

Copyright 2016 Ghent University Library

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.