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 specifications 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 amount 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

            ..

       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.