helpers.py

from string import lower

import ckan.lib.helpers as helpers
import ckan.model as model
import ckan.plugins.toolkit as toolkit

from profilehooks import timecall, profile


def get_collection(dataset_dict):
    collection_id = get_collection_id(dataset_dict)
    if collection_id:
        return get_collection_info(collection_id, dataset_dict)
    
    return None


def get_collection_info(collection_id, dataset_dict=None):
    collection_dict = get_package_dict(collection_id)
    dataset_names = get_dataset_names(collection_dict)
    datasets_in_collection = get_datasets_from_solr(dataset_names)
    collection_info = gather_collection_info(collection_dict, datasets_in_collection, dataset_dict)
    return collection_info


@timecall(immediate=True)
def get_collection_id(dataset_dict):
    relationships_dataset = dataset_dict.get('relationships_as_subject')
    if len(relationships_dataset):        
        return relationships_dataset[0]['__extras']['object_package_id']
    return None


@timecall(immediate=True)
def get_relationships(name):
    pass


def get_package_dict(name):
    return model.Package.get(name).as_dict()


@timecall(immediate=True)
def get_dataset_names(collection_dict):
    relationships_collection = collection_dict.get('relationships')
    names_collection_members = [relationship.get('object') for relationship in relationships_collection]
    return names_collection_members


def get_datasets_from_solr(dataset_names):
    '''
    queries SOLR with a query of the following form:
    package_search?fq=name:(name1+OR+name2)&sort=extras_issued+asc
    '''
    context = None # see https://docs.ckan.org/en/ckan-2.7.3/extensions/plugins-toolkit.html#ckan.plugins.toolkit.ckan.plugins.toolkit.get_action

    name_expression = ' OR '.join(dataset_names)
    fq = 'name:({})'.format(name_expression)
    
    sort = 'name asc,extras_issued asc'
    
    query_result = toolkit.get_action('package_search')(context, {
        'fq': fq,
        'sort': sort,
        'rows': 1000, # maximum possible number of results, see https://docs.ckan.org/en/ckan-2.7.3/api/index.html#ckan.logic.action.get.package_search
    })

    results = query_result.get('results')
    datasets_found = results if results else []

    return datasets_found


def gather_collection_info(collection_dict, datasets_in_collection, dataset_dict=None):
    url_from_id = lambda id: helpers.url_for(controller='package', action='read', id=id)


    name_first_dataset = datasets_in_collection[0].get('name')
    url_first_dataset = url_from_id(name_first_dataset)
    
    name_last_dataset = datasets_in_collection[-1].get('name')
    url_last_dataset = url_from_id(name_last_dataset)

    name_collection = collection_dict.get('name')
    persistent_link_last_member = helpers.url_for(
        controller='ckanext.odsh.collection.controller:LatestDatasetController', 
        action='latest',
        id=name_collection
    )

    if dataset_dict:
        name_current_dataset = dataset_dict.get('name')
        dataset_names = [d.get('name') for d in datasets_in_collection]
        
        def get_predecessor():
            id_current = dataset_names.index(name_current_dataset)
            if id_current and id_current > 0:
                return dataset_names[id_current - 1]
            return None
        
        def get_successor():
            id_current = dataset_names.index(name_current_dataset)
            if id_current and id_current < len(dataset_names) - 1:
                return dataset_names[id_current + 1]
            return None
        
        name_predecessor = get_predecessor()
        url_predecessor = url_from_id(name_predecessor) if name_predecessor else None
        
        name_successor = get_successor()
        url_successor = url_from_id(name_successor) if name_successor else None
    else:
        url_predecessor = url_successor = None
    
    return {
        'title': collection_dict.get('title'),
        'members': datasets_in_collection,
        'first_member': {
            'name': name_first_dataset,
            'url': url_first_dataset,
        },
        'last_member': {
            'name': name_last_dataset,
            'url': url_last_dataset,
        },
        'predecessor': {
            'url': url_predecessor,
        },
        'successor': {
            'url': url_successor,
        },
        'persistent_link_last_member': persistent_link_last_member,
    }






#for mapping latest resources and latest dataset

@timecall(immediate=True)
def get_latest_dataset(collection_name):
    collection_info = get_collection_info(collection_name)
    latest_name = collection_info['last_member']['name']
    return latest_name


@timecall(immediate=True)
def get_latest_resources_for_type(collection_name, type):
    latest_dataset_name = get_latest_dataset(collection_name)
    latest_dataset = get_package_dict(latest_dataset_name)
    resource_list = latest_dataset.get('resources')
    latest_resource = latest_created = latest_id = None
    for resource in resource_list:
        resource_format = resource.get('format')
        resource_created = resource.get('created')
        resource_id = resource.get('id')
        if is_latest_resources(resource_format, type, resource_created, latest_created, resource_id, latest_id):
            latest_id=resource_id
            latest_created=resource_created
            latest_resource=resource
    return latest_resource