pyramid_skosprovider.views

Complexity

Total Complexity

55

Size/Duplication

Total Lines	387
Duplicated Lines	0 %

Importance

Changes

0

# -*- coding: utf8 -*-
'''
This module contains the pyramid views that expose services.
'''

import itertools

from pyramid.view import view_config, view_defaults

from pyramid.httpexceptions import (
    HTTPNotFound,
    HTTPBadRequest
)

from skosprovider.exceptions import ProviderUnavailableException

from pyramid_skosprovider.utils import (
    parse_range_header,
    QueryBuilder
)

from skosprovider.jsonld import (
    MINI_CONTEXT,
    CONTEXT
)

import logging
log = logging.getLogger(__name__)


class RestView(object):

    def __init__(self, request):
        self.request = request
        self.skos_registry = self.request.skos_registry


@view_defaults(renderer='json')
class StaticView(RestView):

    @view_config(
        route_name='skosprovider.context',
        request_method='GET',
        accept='application/json',
        http_cache=(3600, {'public': True})
    )
    @view_config(
        route_name='skosprovider.context',
        request_method='GET',
        accept='application/ld+json',
        http_cache=(3600, {'public': True})
    )
    def get_context(self):
        if 'application/ld+json' in self.request.accept:
            self.request.response.content_type = 'application/ld+json'
        return {
            '@context': CONTEXT
        }


class ProviderView(RestView):
    '''
    A set of views that expose information from a certain provider.
    '''

    @view_config(
        route_name='skosprovider.uri',
        request_method='GET',
        accept='application/json+ld',
        renderer='skosjson'
    )
    @view_config(
        route_name='skosprovider.uri',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    @view_config(
        route_name='skosprovider.uri.deprecated',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    def get_uri(self):
        uri = self.request.params.get('uri', self.request.matchdict.get('uri', None))
        if not uri:
            return HTTPBadRequest()
        if 'application/ld+json' in self.request.accept:
            self.request.response.content_type = 'application/ld+json'
        provider = self.skos_registry.get_provider(uri)
        uri_context = MINI_CONTEXT
        uri_context['concept_scheme'] = {
            '@id': 'skos:inScheme',
            '@type': '@id'
        }
        if provider:
            uri_context['concept_scheme'] = 'skos:ConceptScheme'
            return {
                '@context': uri_context,
                'type': 'concept_scheme',
                'uri': provider.concept_scheme.uri,
                'id': provider.get_vocabulary_id()
            }
        c = self.skos_registry.get_by_uri(uri)
        if not c:
            return HTTPNotFound()
        return {
            '@context': uri_context,
            'type': c.type,
            'uri': c.uri,
            'id': c.id,
            'concept_scheme': {
                'type': 'skos:ConceptScheme',
                'uri': c.concept_scheme.uri,
                'id': self.skos_registry.get_provider(c.concept_scheme.uri).get_vocabulary_id()
            }
        }

    @view_config(
        route_name='skosprovider.conceptschemes',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    @view_config(
        route_name='skosprovider.conceptschemes',
        request_method='GET',
        accept='application/ld+json'
    )
    def get_conceptschemes(self):
        language = self.request.params.get('language', self.request.locale_name)
        if 'application/ld+json' in self.request.accept:
            self.request.response.content_type = 'application/ld+json'
        context = MINI_CONTEXT
        context['subject'] = {
            '@id': 'dct:subject',
            '@type': '@id'
        }
        conceptschemes = []
        for p in self.skos_registry.get_providers():
            try:
                if label := p.concept_scheme.label(language):
                    cslabel = label.label
                else:
                    cslabel = p.get_vocabulary_uri()
            except ProviderUnavailableException as e:
                log.error(f'Could not fetch label for {p.get_vocabulary_uri()}: %s', e)
                cslabel = p.get_vocabulary_uri()
            cs = {
                '@context': context,
                'type': 'skos:ConceptScheme',
                'id': p.get_vocabulary_id(),
                'uri': p.get_vocabulary_uri(),
                'label': cslabel,
                'subject': p.metadata['subject'] if p.metadata['subject'] else []
            }
            conceptschemes.append(cs)
        return conceptschemes

    @view_config(
        route_name='skosprovider.conceptscheme',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    def get_conceptscheme(self):
        scheme_id = self.request.matchdict['scheme_id']
        provider = self.skos_registry.get_provider(scheme_id)
        if not provider:
            return HTTPNotFound()
        language = self.request.params.get('language', self.request.locale_name)
        return {
            'id': provider.get_vocabulary_id(),
            'uri': provider.concept_scheme.uri,
            'label': provider.concept_scheme.label(language).label if provider.concept_scheme.label(language) else None,
            'subject': provider.metadata['subject'] if provider.metadata['subject'] else [],
            'labels': provider.concept_scheme.labels,
            'notes': provider.concept_scheme.notes,
            'sources': provider.concept_scheme.sources,
            'languages': provider.concept_scheme.languages
        }

    @view_config(
        route_name='skosprovider.conceptscheme',
        request_method='GET',
        renderer='skosjsonld',
        accept='application/ld+json'
    )
    @view_config(
        route_name='skosprovider.conceptscheme.jsonld',
        request_method='GET',
        renderer='skosjsonld'
    )
    def get_conceptscheme_jsonld(self):
        scheme_id = self.request.matchdict['scheme_id']
        provider = self.skos_registry.get_provider(scheme_id)
        if not provider:
            return HTTPNotFound()
        return provider.concept_scheme

    @view_config(
        route_name='skosprovider.conceptscheme.tc',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    def get_conceptscheme_top_concepts(self):
        scheme_id = self.request.matchdict['scheme_id']
        provider = self.skos_registry.get_provider(scheme_id)
        if not provider:
            return HTTPNotFound()
        language = self.request.params.get('language', self.request.locale_name)
        return provider.get_top_concepts(language=language)

    @view_config(
        route_name='skosprovider.conceptscheme.display_top',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    def get_conceptscheme_display_top(self):
        scheme_id = self.request.matchdict['scheme_id']
        provider = self.skos_registry.get_provider(scheme_id)
        if not provider:
            return HTTPNotFound()
        language = self.request.params.get('language', self.request.locale_name)
        return provider.get_top_display(language=language)

    def _build_providers(self, request):
        '''
        :param pyramid.request.Request request:
        :rtype: :class:`dict`
        '''
        # determine targets
        providers = {}
        ids = request.params.get('providers.ids', None)
        if ids:
            ids = ids.split(',')
            providers['ids'] = ids
        subject = self.request.params.get('providers.subject', None)
        if subject:
            providers['subject'] = subject
        return providers

    @view_config(
        route_name='skosprovider.cs',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    def get_concepts(self):
        qb = QueryBuilder(self.request)
        query = qb()
        kwargs = {"language": qb.language, "providers": self._build_providers(self.request)}
        kwargs.update(self._get_sort_params())
        if qb.no_result:
            concepts = []
        else:
            concepts = self.skos_registry.find(query, **kwargs)
            # Flatten it all
            concepts = list(itertools.chain.from_iterable([c['concepts'] for c in concepts]))

        if qb.postprocess:
            concepts = self._postprocess_wildcards(concepts, qb.label)

        return self._page_results(concepts)

    @view_config(
        route_name='skosprovider.conceptscheme.cs',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    def get_conceptscheme_concepts(self):
        scheme_id = self.request.matchdict['scheme_id']
        provider = self.skos_registry.get_provider(scheme_id)
        if not provider:
            return HTTPNotFound()
        qb = QueryBuilder(self.request)
        query = qb()
        kwargs = {"language": qb.language}
        kwargs.update(self._get_sort_params())
        if qb.no_result:
            concepts = []
        else:
            concepts = provider.find(query, **kwargs)

        if qb.postprocess:
            concepts = self._postprocess_wildcards(concepts, qb.label)

        return self._page_results(concepts)

    @staticmethod
    def _postprocess_wildcards(concepts, label):
        # We need to refine results further
        if label.startswith('*') and not label.endswith('*'):
            concepts = [
                c for c in concepts if c['label'].lower().endswith(label[1:].lower())
            ]
        elif label.endswith('*') and not label.startswith('*'):
            concepts = [
                c for c in concepts if c['label'].lower().startswith(label[:-1].lower())
            ]
        return concepts

    def _get_sort_params(self):
        sort = self.request.params.get('sort', None)
        # Result sorting
        if sort:
            sort_order = 'desc' if sort[0:1] == '-' else 'asc'
            sort = sort[1:] if sort[0:1] in ['-', '+'] else sort
            sort = sort.strip().lower()  # dojo store does not encode '+'
            return {"sort": sort, "sort_order": sort_order}
        return {}

    def _page_results(self, concepts):
        # Result paging
        paging_data = False
        if 'Range' in self.request.headers:
            paging_data = parse_range_header(self.request.headers['Range'])
        count = len(concepts)
        if not paging_data:
            paging_data = {
                'start': 0,
                'finish': count - 1 if count > 0 else 0,
                'number': count
            }
        cslice = concepts[paging_data['start']:paging_data['finish']+1]
        if len(cslice):
            cslice[0]['@context'] = self.request.route_url('skosprovider.context')
        self.request.response.headers['Content-Range'] = \
            'items %d-%d/%d' % (
                paging_data['start'], paging_data['finish'], count
            )
        return cslice

    @view_config(
        route_name='skosprovider.c',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    @view_config(
        route_name='skosprovider.c',
        request_method='GET',
        renderer='skosjsonld',
        accept='application/ld+json'
    )
    @view_config(
        route_name='skosprovider.c.jsonld',
        request_method='GET',
        renderer='skosjsonld'
    )
    def get_concept(self):
        scheme_id = self.request.matchdict['scheme_id']
        concept_id = self.request.matchdict['c_id']
        provider = self.skos_registry.get_provider(scheme_id)
        if not provider:
            return HTTPNotFound()
        concept = provider.get_by_id(concept_id)
        if not concept:
            return HTTPNotFound()
        return concept

    @view_config(
        route_name='skosprovider.c.display_children',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'
    )
    def get_concept_display_children(self):
        scheme_id = self.request.matchdict['scheme_id']
        concept_id = self.request.matchdict['c_id']
        provider = self.skos_registry.get_provider(scheme_id)
        if not provider:
            return HTTPNotFound()
        language = self.request.params.get('language', self.request.locale_name)
        children = provider.get_children_display(concept_id, language=language)
        if children is False:
            return HTTPNotFound()
        return children

    @view_config(
        route_name='skosprovider.c.expand',
        request_method='GET',
        accept='application/json',
        renderer='skosjson'