def get_schema():
    """Schema structure of this resource

    :return: schema dictionary
    :rtype: dict
    """
    return {'mongo_indexes': {'index_updated': [('_updated', 1)],
        'index_created': [('_created', 1)], 'index_host': [('host', 1)],
        'index_host_name': [('host_name', 1)], 'index_service': [('service',
        1)], 'index_service_name': [('service_name', 1)],
        'index_host_service_name': [('host_name', 1), ('service_name', 1)]},
        'schema': {'schema_version': {'type': 'integer', 'default': 3},
        'host': {'schema_version': 2, 'title': 'Concerned host identifier',
        'type': 'objectid', 'data_relation': {'resource': 'host',
        'embeddable': True}, 'nullable': True}, 'host_name': {
        'schema_version': 1, 'title': 'Host name', 'comment':
        'The backend stores the host name. This allows to keep an information about the concerned host even if it has been deleted from the backend.'
        , 'type': 'string', 'regex': '^[^`~!$%^&*"|\'<>?,()=]+$'},
        'service': {'schema_version': 2, 'title':
        'Concerned service identifier', 'comment':
        'If not set, this check result is an host check', 'type':
        'objectid', 'data_relation': {'resource': 'service', 'embeddable': 
        True}, 'nullable': True}, 'service_name': {'schema_version': 1,
        'title': 'Service name', 'comment':
        'The backend stores the service name. This allows to keep an information about the concerned service even if it has been deleted from the backend.'
        , 'type': 'string', 'regex': '^[^`~!$%^&*"|\'<>?,()=]+$'}, 'state':
        {'schema_version': 1, 'title': 'State', 'type': 'string', 'allowed':
        ['UP', 'DOWN', 'UNREACHABLE', 'OK', 'WARNING', 'CRITICAL',
        'UNKNOWN'], 'required': True}, 'state_type': {'schema_version': 1,
        'title': 'State type', 'type': 'string', 'allowed': ['HARD', 'SOFT'
        ], 'required': True}, 'state_id': {'schema_version': 1, 'title':
        'State identifier', 'type': 'integer', 'default': 0},
        'passive_check': {'schema_version': 1, 'title': 'Passive check',
        'type': 'boolean', 'default': False}, 'acknowledged': {
        'schema_version': 1, 'title': 'Acknowledged', 'type': 'boolean',
        'default': False}, 'acknowledgement_type': {'schema_version': 1,
        'title': 'Acknowledgement type', 'type': 'integer', 'default': 1},
        'downtimed': {'schema_version': 1, 'title': 'Downtimed', 'type':
        'boolean', 'default': False}, 'last_check': {'schema_version': 1,
        'title': 'Check timestamp', 'type': 'integer', 'default': 0},
        'last_state': {'schema_version': 1, 'title': 'Last state', 'type':
        'string', 'default': 'OK', 'allowed': ['OK', 'WARNING', 'CRITICAL',
        'UNKNOWN', 'UP', 'DOWN', 'UNREACHABLE']}, 'last_state_type': {
        'schema_version': 1, 'title': 'Last state type', 'type': 'string',
        'allowed': ['HARD', 'SOFT'], 'required': True}, 'last_state_id': {
        'schema_version': 1, 'title': 'Last state identifier', 'type':
        'integer', 'default': 0}, 'output': {'schema_version': 1, 'title':
        'Output', 'type': 'string', 'default': ''}, 'long_output': {
        'schema_version': 1, 'title': 'Long output', 'type': 'string',
        'default': ''}, 'perf_data': {'schema_version': 1, 'title':
        'Performance data', 'type': 'string', 'default': ''}, 'latency': {
        'schema_version': 1, 'title': 'Latency', 'type': 'float', 'default':
        0.0}, 'execution_time': {'schema_version': 1, 'title':
        'Execution time', 'type': 'float', 'default': 0.0},
        'current_attempt': {'schema_version': 2, 'title':
        'Current attempt number', 'comment': '', 'type': 'integer',
        'default': 0}, 'state_changed': {'schema_version': 1, 'title':
        'State changed', 'comment':
        'The state has changed with the last check?', 'type': 'boolean',
        'default': False}, 'last_state_changed': {'schema_version': 1,
        'title': 'Last state changed', 'comment':
        'Last time the state changed', 'type': 'integer', 'default': 0},
        'last_hard_state_changed': {'schema_version': 2, 'title':
        'Last time hard state changed', 'comment':
        'Last time this element hard state has changed.', 'type': 'integer',
        'default': 0}, 'last_time_0': {'schema_version': 2, 'title':
        'Last time up/ok', 'comment': 'Last time this element was Up/Ok.',
        'type': 'integer', 'default': 0}, 'last_time_1': {'schema_version':
        2, 'title': 'Last time Down/Warning', 'comment':
        'Last time this element was Down/Warning.', 'type': 'integer',
        'default': 0}, 'last_time_2': {'schema_version': 2, 'title':
        'Last time critical', 'comment':
        'Last time this element was Critical.', 'type': 'integer',
        'default': 0}, 'last_time_3': {'schema_version': 2, 'title':
        'Last time unknown', 'comment':
        'Last time this element was Unknown.', 'type': 'integer', 'default':
        0}, 'last_time_4': {'schema_version': 2, 'title':
        'Last time unreachable', 'comment':
        'Last time this element was Unreachable.', 'type': 'integer',
        'default': 0}, '_realm': {'schema_version': 1, 'title': 'Realm',
        'comment': 'Realm this element belongs to.', 'type': 'objectid',
        'data_relation': {'resource': 'realm', 'embeddable': True}},
        '_sub_realm': {'schema_version': 1, 'title': 'Sub-realms',
        'comment':
        'Is this element visible in the sub-realms of its realm?', 'type':
        'boolean', 'default': True}, '_users_read': {'schema_version': 1,
        'type': 'list', 'schema': {'type': 'objectid', 'data_relation': {
        'resource': 'user', 'embeddable': True}}}}, 'schema_deleted': {
        'max_attempts': {'schema_version': 3, 'title': 'Maximum attempts',
        'comment': '', 'type': 'integer', 'default': 0}}}
