A flask web application that crawls Activity Streams for IIIF Canvases and offers a search API.

Project state

Canvas Indexer is being developed as part of the CODH's IIIF Curation Platform, but meant to be a general IIIF tool. Integration into the IIIF Curation Platform means that in this very early stage there is a focus on cr:Curation^[1] type documents.^[2] Nevertheless all development is done with generality in mind.^[3]

[1] http://codh.rois.ac.jp/iiif/curation/1#Curation
[2] The crawler currently only looks for canvases within them (and not, for example, sc:Manifests) and the search API offers dedicated parameters.
[3] The crawling process implements the IIIF Change Discovery API 0.1 and extending the indexing mechanism and search API to support IIIF documents within Activity Streams in general (or at least sc:Manifests for a first step) should be straightforward.

Setup

• create virtual environment: $ python3 -m venv venv
• activate virtual environment: $ source venv/bin/activate
• install requirements: $ pip install -r requirements.txt

Config

section	key	default	explanation
shared	db_uri	sqlite:////tmp/ci_tmp.db	a SQLAlchemy database URI (file system paths have to be absolute)
crawler	as_sources	[]	comma seperated list of links to Activity Streams in form of OrderedCollections
‌	interval	3600	crawl interval in seconds (value <=0 deactivates automatic crawling)
‌	log_file	/tmp/ci_crawl_log.txt	file system path to where the crawling details should be logged
‌	allow_orphan_canvases	false	set whether or not Canvases, that are not associated with any parent elements in the index anymore, should still appear in search results
api	server_url	http://localhost:5005	URL under which Canvas Indexer can be accessed (only needed when using bots (details below))
‌	bot_urls	[]	comma seperated list of URLs to bots (only needed when using bots (details below))
‌	facet_label_sort_top	[]	comma seperated list defining the beginning of the list returned for the /facets endpoint
‌	facet_label_sort_bottom	[]	comma seperated list defining the end of the list returned for the /facets endpoint
‌	facet_value_sort_frequency	[]	comma seperated list of facets to be sorted by frequency
‌	facet_value_sort_alphanum	[]	comma seperated list of facets to be sorted alphanumerically
facet_value_sort_ custom_<name>	label	‌	facet label for which a custom order is defined
‌	sort_top	‌	comma seperated list defining the beginning
‌	sort_bottom	‌	comma seperated list defining the end

Run

$ source venv/bin/activate
$ python3 run.py [debug]

API

path: {base_url}/api
arguments:

arg	default	explanation
select	curation	set the type of search results to be returned to either canvas or curation
from	curation,canvas	set the type of metadata the search results should be based on to canvas, curation or a comma seperated list of aforementioned
where		search keyword
where_metadata_label		used to search by a property+value pair. requires where_metadata_value
where_metadata_value		used to search by a property+value pair. requires where_metadata_label
where_agent	human,machine	set the type of metadata creator to human, machine or a comma seperated list of aforementioned
start	0	0 based index from which to start listing results from the list of all results
limit	null meaning no limit	limit the number of results being returned

example: {base_url}/api?select=canvas&from=canvas,curation&where=face

path: {base_url}/facets
returns a pre generated overview of the indexed metadata facets

Crawler

• The crawler can be configured to run periodically (see Config) or triggered manually by accessing {base_url}/crawl.
• On its first run the crawler will go through an Activity Stream in its entirety, subsequent runs will only regard Activities that occured after the previous run.
• In its current state the crawler indexes only the label value pairs given in a IIIF resource's metadata property.

Bot integration

Canvas Indexer can be set up to send image URLs of the canvases it indexes to bots that return tags. These tags are then integrated in the index. Example code of a bot can be found in the folder bot_example.

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Logo

The Canvas Indexer logo uses image content from 絵本花葛蘿 in the 日本古典籍データセット（国文研所蔵） provided by the Center for Open Data in the Humanities, used under CC-BY-SA 4.0. The Canvas Indexer logo is licensed under CC-BY-SA 4.0 by Tarek Saier. A high resolution version (4456×2326 px) can be downloaded here.

Support

Sponsored by the National Institute of Informatics.
Supported by the Center for Open Data in the Humanities, Joint Support-Center for Data Science Research, Research Organization of Information and Systems.