Command-line shuffle

Posted by Michael Giarlo on September 26, 2009

Being a nerd, I tend to like the command-line. When I'm working on my laptop at home, I tend to like listening to music. Before I discovered that mplayer had a really convenient shuffle idiom, I would invoke it thusly (to listen to all my Pavement tracks in shuffle mode):

export IFS=$'\n'
for track in $(find /mnt/upnp/MediaTomb/Audio/Artists/Pavement -name \*.mp3 | ~/bin/shuffle.py); do mplayer $track; done

And the wee shuffle script I whipped together looks like this:

#!/usr/bin/env python
# shuffle.py
 
import sys
import random
 
args = list(sys.stdin)
random.shuffle(args)
sys.stdout.writelines(args)

And here's the convenient shuffle idiom that renders my arg-shuffling script somewhat useless:

find /mnt/upnp/MediaTomb/Audio/Artists/Pavement -name \*.mp3 | mplayer -playlist - -shuffle -loop 0

JSONovich emerges

Posted by Michael Giarlo on August 24, 2009

JSONovich has now emerged from the Mozilla Add-ons sandbox and is available to the masses: http://addons.mozilla.org/en-US/firefox/addon/10122.

Linking World Digital Library Data

Posted by Michael Giarlo on August 10, 2009

As I mentioned earlier, I've been learning about linked data in the context of dropping it into the World Digital Library project. I am hopeful we'll be able to deploy the RDF views[1] before too long. In advance of that, I thought it might be helpful to share a sample of what our RDF would look like. The RDF below represents the WDL item for the U.S. Constitution. I appreciate constructive criticism.

A few things to note:

  • Mmm, Unicode.
  • Item types are from the Bibliographic Ontology.
  • Most of the properties are from the Dublin Core Metadata Element Set ontology, especially used where literals are objects rather than resources identified by URI.
  • Where possible I dug up or found URIs and used the Dublin Core Metadata Terms ontology.
  • An item is modeled as an aggregation of its constituent files, as defined in OAI-ORE. The notion here is that an ORE aggregation of an item, as expressed in a resource map which is discoverable via a link header in each item detail page, is a "whole" item, including all of its files[2], metadata, and translations.
  • I'm also making light use of the NEPOMUK File Ontology to express that constituent files are files, and to be explicit about file sizes so that folks know in advance of retrieving it how large files are.
  • Links out to DDC (Decimalised Database of Concepts), Lingvoj, DBpedia, and Library of Congress Authorities & Vocabularies (e.g., LC Subject Headings) are included where possible. [3] I'd be especially stoked to hear of other vocabs I might link to. The more linked the data, the better.
  • The output below is Turtle for readability, but the application will offer up RDF/XML.

The data after the jump:
Continue reading…

Notes
  1. Sadly, the URIs are uglyish due to some constraints from our caching configuration. I figure we can redirect uglyish URIs to cool ones and make use of owl:sameAs if those constraints go away. []
  2. sans certain low-quality derivatives such as small thumbnails and tiles for the zoom interface []
  3. I was poking through the DBpedia output for Geonames URIs as well, but my method was way too slow and clunky, so that's disabled for the time being. Clients can always follow their noses from the DBpedia output. []


Validating ORE from the Command-line

Posted by Michael Giarlo on July 31, 2009

I've been periodically poking at getting Linked Data/RDF views hooked into the World Digital Library web application, following Ed Summers' lead from his work on Chronicling America. The RDF views also use the OAI-ORE vocabulary to express aggregations — in WDL, an item is an aggregation of its constituent files. The goal is to provide a semantically rich and holistic representation of a WDL item (identifier, constituent files, metadata, translations, and so on).

The ORE format is a new one for me so it's hard to say whether the output of my dev branch is valid ORE or not. Plus I'm a sucker for validators. Turns out Rob Sanderson has developed a Python library for validating ORE, and this little snippet is what I've been using to validate the ORE. I didn't put much effort into making it readable, so much as banging something functional out so I can meet deadlines, so mea culpa and all that. But without further hemming and hawing, the code:

# validate.py
import sys
from foresite import *
 
rem = RdfLibParser().parse(ReMDocument(sys.argv[1]))
aggr = rem.aggregation
n3 = RdfLibSerializer('n3')
rem2 = aggr.register_serialization(n3)
print rem2.get_serialization(n3).data

Most of this code is naively copied and pasted from Rob's excellent Foresite documentation.

I invoke it thusly: python validate.py {URL}

And the output:

@prefix _27: <http://www.semanticdesktop.org/ontologies/nfo#>.
@prefix _28: <http://localhost/en/item/1/id#>.
@prefix _29: <http://localhost/en/item/1/>.
@prefix bibo: <http://purl.org/ontology/bibo/>.
@prefix dc: <http://purl.org/dc/elements/1.1/>.
@prefix dcterms: <http://purl.org/dc/terms/>.
@prefix ore: <http://www.openarchives.org/ore/terms/>.
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>.
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>.
@prefix rdfs1: <http://www.w3.org/2001/01/rdf-schema#>.
 
 _28:ResourceMap a ore:ResourceMap;
     dc:format "text/rdf+n3";
     dcterms:created "2009-07-31T14:23:31Z";
     dcterms:modified "2009-07-31T14:23:31Z";
     ore:describes _29:id. 
 
 _29:id a bibo:Image,
         ore:Aggregation;
     dcterms:DDC "973";
     dcterms:alternative "Antietam, Maryland. Allan Pinkerton, President Lincoln, and Major General John A. McClernand"@en;
     dcterms:created "1862年10月3日"@zh,
         "3 de octubre de 1862"@es,
         "3 de outubro de 1862"@pt,
         "3 octobre 1862"@fr,
         "3 октября 1862 года"@ru,
         "October 3, 1862"@en,
         " ٣ آكتوبر، ١٨٦٢"@ar;
     dcterms:creator "Gardner, Alexander"@en,
         "Gardner, Alexander"@es,
         "Gardner, Alexander"@fr,
         "Gardner, Alexander"@pt,
         "Гарднер, Александр"@ru,
         "جاردنر, أليكسندر"@ar,
         "加德纳, 亚历山大"@zh;
... (and so on and so forth)
     dcterms:title "Antietam, Maryland. Allan Pinkerton, President Lincoln, and Major General John A. McClernand: Another View"@en,
         "Antietam, Maryland. Allan Pinkerton, el Presidente Lincoln y el General Principal John A. McClernand: Otra visión"@es,
         "Antietam, Maryland. Allan Pinkerton, le président Lincoln et le général-major John A. McClernand: Autre vue"@fr,
         "Antietam, Maryland. Allan Pinkerton,  Presidente Lincoln e Major-General John A. McClernand: Outra Vista"@pt,
         "Антитэм, штат Мэриленд. Аллан Пинкертон, президент Линкольн и генерал-майор Джон А. Макклернанд: Другой снимок"@ru,
         "أنتينام، ميريلاند ألان بينكرتون، الرئيس لينكولن، واللواء جون أ. ماكليرناند: منظر آخر"@ar,
         "安蒂特姆,马里兰州 艾伦·平克顿、林肯总统和少将约翰·A ·马克克拉南: 另一个视角"@zh;
     ore:aggregates <http://localhost/static/c/1/reference/04326u_thumb_item.gif>,
         <http://localhost/static/c/1/service/04326u.tif>;
     ore:isDescribedBy <http://localhost/en/item/1/item.rdf>;
     rdfs:seeAlso <http://hdl.loc.gov/loc.wdl/dlc.1>. 
 
 <http://localhost/static/c/1/reference/04326u_thumb_item.gif> a _27:FileDataObject;
     dcterms:format "image/gif";
     _27:fileSize "34531"^^<http://www.w3.org/2001/XMLSchema#long>. 
 
 <http://localhost/static/c/1/service/04326u.tif> a _27:FileDataObject;
     dcterms:format "image/tiff";
     _27:fileSize "1301614"^^<http://www.w3.org/2001/XMLSchema#long>. 
 
 ore:Aggregation rdfs1:isDefinedBy <http://www.openarchives.org/ore/terms/>;
     rdfs1:label "Aggregation". 
 
 ore:ResourceMap rdfs1:isDefinedBy <http://www.openarchives.org/ore/terms/>;
     rdfs1:label "ResourceMap".

You might pick up on some warts I have yet to fix, but there you go.

WDL metadata mapping, and, parsing TEI in Python

Posted by Michael Giarlo on July 13, 2009

Context

Early on in the effort to develop the first public version of the World Digital Library web application, we developed a (non-public) Django-based cataloging application where Library of Congress catalogers could manage metadata for WDL items. Management in this sense includes creation of records, editing of records, versioning of edits, mapping of source records, and some light workflow for assignment of records to individual catalogers and for hooking into translation processes[1].

I worked primarily on the source record mapping tools. They take a number of formats as input and are called by the cataloging application to map metadata from these formats into the WDL domain model. Several though not all of which are XML-based, and thus easily dealt with in Python, via the etree module in the lxml package.

Dan recently kicked off a new R&D project for evaluating (any) metadata against any number of metadata profiles, mapping into a generic data dictionary, the goal being to determine how feasible it would be to develop a toolset for aiding remediation of metadata across any number of digital collections. I have been working on this project with Dan, and got started by seeing how generalizable the WDL metadata mapping tools are. Turns out they're fairly generalizable once you tweak the various format-specific mapping rules to map into the generic data dictionary model rather than the WDL model (around 15 elements, and somewhere between Dublin Core and MODS in terms of specificity but flatly structured like DC).

Some of the test data I am working with now, that has nothing to do with WDL, is SGML-based TEI 2 markup. The closest I worked with on WDL was TEI P5 for manuscript description which is serialized in XML. Turns out my TEI mapping rules from before blew up on this TEI 2 stuff, as lxml.etree (naturally) wasn't digging the non-XML input. I googled around a bit for how best to parse TEI (or any SGML) in Python and then discovered it's actually simple as pie.

Code

If you've got the BeautifulSoup module installed[2]:

>>> from BeautifulSoup import BeautifulSoup
>>> tei = open('foo.sgm').read()
>>> BeautifulSoup(tei).findAll('title')[0].string
u'[Memorandum to Dr. Botkin]: a machine readable transcription.'

If not, the lxml.html module works too:

>>> from lxml import html
>>> h = html.parse(open('foo.sgm'))
>>> h.xpath('//title')[0].text
'[Memorandum to Dr. Botkin]: a machine readable transcription.'

Data

And here's what the sample data looks like:

<!doctype tei2 public "-//Library of Congress - Historical Collections (American Memory)//DTD ammem.dtd//EN" 
[
<!entity % images system "07010101.ent"> %images;
]>
<tei2>
<teiheader type="text" date.created="1994/03/15" date.updated="2002/04/05" status="updated" creator="National Digital Library Program
, Library of Congress">
<filedesc>
<titlestmt>
<amid type="aggitemid">wpa0-07010101</amid>
<title>[Memorandum to Dr. Botkin]: a machine readable transcription.</title>
<amcol><amcolname>Life Histories from the Folklore Project, WPA Federal Writers&apos; Project, 1936-1940; American Memory, Library of Congress.</amcolname><amcolid type="aggid"></amcolid>
</amcol>
<respstmt>
<resp>Selected and converted.</resp>
<name>American Memory, Library of Congress.</name>
</respstmt></titlestmt>
<publicationstmt>
<p>Washington, DC, 1994.</p>
<p>Preceding element provides place and date of transcription only.</p>
<p>For more information about this text and this American Memory collection, refer to accompanying matter.</p>
</publicationstmt>
<sourcedesc>
<lccn></lccn>
<sourcecol>U.S. Work Projects Administration, Federal Writers&apos; Project (Folklore Project, Life Histories, 1936-39); Manuscript Division, Library of Congress.</sourcecol>
<copyright>Copyright status not determined; refer to accompanying matter.</copyright></sourcedesc>
</filedesc>
<encodingdesc>
<projectdesc><p>The National Digital Library Program at the Library of Congress makes digitized historical materials available for education and scholarship.</p></projectdesc>
<editorialdecl><p>This transcription is intended to have an accuracy of 99.95 percent or greater and is not intended to reproduce the appearance of the original work.  The accompanying images provide a facsimile of this work and represent the appearance of the original.</p></editorialdecl>
<encodingdate>1994/03/15</encodingdate>
<revdate>2002/04/05</revdate>
</encodingdesc>
</teiheader>
<text type="manuscript">
<body>
<div>
<pageinfo>
<controlpgno entity="I07010101">0001</controlpgno>
<printpgno></printpgno></pageinfo>
<p>Memorandum to Dr. Botkin from G. B. Roberts, May 26, 1941</p>
<p>Subject:  Alabama Material</p>
<p>This material has not yet been accessioned and has only 
<del rend="overstrike">beeen</del> been roughly classified as life histories, folklore, and miscellaneous data and copy save in the case of the 2 ex-slave items and the essay on Jesse Owens, each of which was recommended.</p>
<p>Total no. of items recommended:  3 (14 pp.) 
<handwritten>In progress</handwritten></p></div></body></text></tei2>
Notes
  1. Catalogers cataloged stuff in the English language, but every metadata record needed to be translated into the other six U.N. languages: Spanish, Russian, French, Arabic, Chinese, and Portuguese. []
  2. And you are but one sudo easy_install BeautifulSoup away from that. []