diff options
| -rw-r--r-- | mediagoblin/static/metadata/mediagoblin-0.1.dev.jsonld | 47 | ||||
| -rw-r--r-- | mediagoblin/tools/metadata.py | 106 |
2 files changed, 153 insertions, 0 deletions
diff --git a/mediagoblin/static/metadata/mediagoblin-0.1.dev.jsonld b/mediagoblin/static/metadata/mediagoblin-0.1.dev.jsonld new file mode 100644 index 00000000..20a71b53 --- /dev/null +++ b/mediagoblin/static/metadata/mediagoblin-0.1.dev.jsonld @@ -0,0 +1,47 @@ +{ + "@context": { + "qb": "http://purl.org/linked-data/cube#", + "grddl": "http://www.w3.org/2003/g/data-view#", + "ma": "http://www.w3.org/ns/ma-ont#", + "owl": "http://www.w3.org/2002/07/owl#", + "rdf": "http://www.w3.org/1999/02/22-rdf-syntax-ns#", + "rdfa": "http://www.w3.org/ns/rdfa#", + "rdfs": "http://www.w3.org/2000/01/rdf-schema#", + "rif": "http://www.w3.org/2007/rif#", + "rr": "http://www.w3.org/ns/r2rml#", + "skos": "http://www.w3.org/2004/02/skos/core#", + "skosxl": "http://www.w3.org/2008/05/skos-xl#", + "wdr": "http://www.w3.org/2007/05/powder#", + "void": "http://rdfs.org/ns/void#", + "wdrs": "http://www.w3.org/2007/05/powder-s#", + "xhv": "http://www.w3.org/1999/xhtml/vocab#", + "xml": "http://www.w3.org/XML/1998/namespace", + "xsd": "http://www.w3.org/2001/XMLSchema#", + "prov": "http://www.w3.org/ns/prov#", + "sd": "http://www.w3.org/ns/sparql-service-description#", + "org": "http://www.w3.org/ns/org#", + "gldp": "http://www.w3.org/ns/people#", + "cnt": "http://www.w3.org/2008/content#", + "dcat": "http://www.w3.org/ns/dcat#", + "earl": "http://www.w3.org/ns/earl#", + "ht": "http://www.w3.org/2006/http#", + "ptr": "http://www.w3.org/2009/pointers#", + "cc": "http://creativecommons.org/ns#", + "ctag": "http://commontag.org/ns#", + "dc": "http://purl.org/dc/terms/", + "dc11": "http://purl.org/dc/elements/1.1/", + "dcterms": "http://purl.org/dc/terms/", + "foaf": "http://xmlns.com/foaf/0.1/", + "gr": "http://purl.org/goodrelations/v1#", + "ical": "http://www.w3.org/2002/12/cal/icaltzd#", + "og": "http://ogp.me/ns#", + "rev": "http://purl.org/stuff/rev#", + "sioc": "http://rdfs.org/sioc/ns#", + "v": "http://rdf.data-vocabulary.org/#", + "vcard": "http://www.w3.org/2006/vcard/ns#", + "schema": "http://schema.org/", + "describedby": "http://www.w3.org/2007/05/powder-s#describedby", + "license": "http://www.w3.org/1999/xhtml/vocab#license", + "role": "http://www.w3.org/1999/xhtml/vocab#role" + } +} diff --git a/mediagoblin/tools/metadata.py b/mediagoblin/tools/metadata.py new file mode 100644 index 00000000..428e425c --- /dev/null +++ b/mediagoblin/tools/metadata.py @@ -0,0 +1,106 @@ +# GNU MediaGoblin -- federated, autonomous media hosting +# Copyright (C) 2011, 2012 MediaGoblin contributors. See AUTHORS. +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + + +import os +import copy +import json +import re +from pkg_resources import resource_filename + +import dateutil.parser +from pyld import jsonld +from jsonschema import validate, FormatChecker, draft4_format_checker +from jsonschema.compat import str_types + + +MEDIAGOBLIN_CONTEXT_PATH = resource_filename( + "mediagoblin", + os.path.sep.join(["static", "metadata", "mediagoblin-0.1.dev.jsonld"])) +MEDIAGOBLIN_CONTEXT = json.loads(file(MEDIAGOBLIN_CONTEXT_PATH).read()) + + +######################################################## +## Set up the MediaGoblin format checker for json-schema +######################################################## + +URL_REGEX = re.compile( + r'^[a-z]+://([^/:]+|([0-9]{1,3}\.){3}[0-9]{1,3})(:[0-9]+)?(\/.*)?$', + re.IGNORECASE) + +def is_uri(instance): + """ + jsonschema uri validator + """ + if not isinstance(instance, str_types): + return True + + return URL_REGEX.match(instance) + +def is_datetime(instance): + """ + Is a date or datetime readable string. + """ + if not isinstance(instance, str_types): + return True + + return dateutil.parser.parse(instance) + + +class DefaultChecker(FormatChecker): + """ + Default MediaGoblin format checker... extended to include a few extra things + """ + checkers = copy.deepcopy(draft4_format_checker.checkers) + + +DefaultChecker.checkers[u"uri"] = (is_uri, ()) +DefaultChecker.checkers[u"date-time"] = (is_datetime, (ValueError, TypeError)) +DEFAULT_CHECKER = DefaultChecker() + +# Crappy default schema, checks for things we deem important + +DEFAULT_SCHEMA = { + "$schema": "http://json-schema.org/schema#", + + "type": "object", + "properties": { + "dcterms:rights": { + "format": "uri", + "type": "string", + }, + "dcterms:created": { + "format": "date-time", + "type": "string", + } + }, +} + + +def compact_and_validate(metadata, context=MEDIAGOBLIN_CONTEXT, + schema=DEFAULT_SCHEMA): + """ + compact json with supplied context, check against schema for errors + + raises an exception (jsonschema.exceptions.ValidationError) if + there's an error. + + You may wish to do this validation yourself... this is just for convenience. + """ + compacted = jsonld.compact(metadata, context) + validate(metadata, schema, format_checker=DEFAULT_CHECKER) + + return compacted |