cliquet/__init__.py

"""Main entry point
"""
import pkg_resources

import structlog
from cornice import Service as CorniceService
from pyramid.settings import aslist


# Main Cliquet logger.
logger = structlog.get_logger()

from cliquet import errors
from cliquet.initialization import (  # NOQA
    initialize, initialize_cliquet, install_middlewares,
    load_default_settings)
from cliquet.utils import follow_subrequest


# Module version, as defined in PEP-0396.
__version__ = pkg_resources.get_distribution(__package__).version

# The API version, incremented when Python API has breaking change.
API_VERSION = '%s' % __version__.split('.')[0]
# The protocol version, incremented when HTTP API has breaking change.
PROTOCOL_VERSION = API_VERSION


DEFAULT_SETTINGS = {
    'backoff': None,
    'batch_max_requests': 25,
    'cache_backend': '',
    'cache_url': '',
    'cache_pool_size': 25,
    'cors_origins': '*',
    'cors_max_age_seconds': 3600,
    'eos': None,
    'eos_message': None,
    'eos_url': None,
    'error_info_link': 'https://github.com/mozilla-services/cliquet/issues/',
    'http_host': None,
    'http_scheme': None,
    'id_generator': 'cliquet.storage.generators.UUID4',
    'includes': '',
    'initialization_sequence': (
        'cliquet.initialization.setup_request_bound_data',
        'cliquet.initialization.setup_json_serializer',
        'cliquet.initialization.setup_logging',
        'cliquet.initialization.setup_storage',
        'cliquet.initialization.setup_permission',
        'cliquet.initialization.setup_cache',
        'cliquet.initialization.setup_requests_scheme',
        'cliquet.initialization.setup_trailing_slash_redirection',
        'cliquet.initialization.setup_version_redirection',
        'cliquet.initialization.setup_deprecation',
        'cliquet.initialization.setup_authentication',
        'cliquet.initialization.setup_backoff',
        'cliquet.initialization.setup_statsd',
        'cliquet.initialization.setup_listeners'
    ),
    'event_listeners': '',
    'logging_renderer': 'cliquet.logs.ClassicLogRenderer',
    'newrelic_config': None,
    'newrelic_env': 'dev',
    'paginate_by': None,
    'permission_backend': '',
    'permission_url': '',
    'permission_pool_size': 25,
    'profiler_dir': '/tmp',
    'profiler_enabled': False,
    'project_docs': '',
    'project_name': '',
    'project_version': '',
    'readonly': False,
    'retry_after_seconds': 30,
    'statsd_prefix': 'cliquet',
    'statsd_url': None,
    'storage_backend': '',
    'storage_url': '',
    'storage_max_fetch_size': 10000,
    'storage_pool_size': 25,
    'transaction_per_request': True,
    'userid_hmac_secret': '',
    'version_prefix_redirect_enabled': True,
    'trailing_slash_redirect_enabled': True,
    'multiauth.groupfinder': 'cliquet.authorization.groupfinder',
    'multiauth.policies': 'basicauth',
    'multiauth.policy.basicauth.use': ('cliquet.authentication.'
                                       'BasicAuthAuthenticationPolicy'),
    'multiauth.authorization_policy': ('cliquet.authorization.'
                                       'AuthorizationPolicy')
}


class Service(CorniceService):
    """Subclass of the default cornice service.

    This is useful in order to attach specific behaviours without monkey
    patching the default cornice service (which would impact other uses of it)
    """
    default_cors_headers = ('Backoff', 'Retry-After', 'Alert',
                            'Content-Length')

    def error_handler(self, error):
        return errors.json_error_handler(error)

    @classmethod
    def init_from_settings(cls, settings):
        cls.cors_origins = tuple(aslist(settings['cors_origins']))
        cors_max_age = settings['cors_max_age_seconds']
        cls.cors_max_age = int(cors_max_age) if cors_max_age else None


def includeme(config):
    settings = config.get_settings()

    # Heartbeat registry.
    config.registry.heartbeats = {}

    # Public settings registry.
    config.registry.public_settings = {'batch_max_requests', 'readonly'}

    # Setup cornice.
    config.include("cornice")

    # Per-request transaction.
    config.include("pyramid_tm")

    # Add CORS settings to the base cliquet Service class.
    Service.init_from_settings(settings)

    # Setup components.
    for step in aslist(settings['initialization_sequence']):
        step_func = config.maybe_dotted(step)
        step_func(config)

    # Include cliquet plugins after init, unlike pyramid includes.
    includes = aslist(settings['includes'])
    for app in includes:
        config.include(app)

    # # Show settings to output.
    # for key, value in settings.items():
    #     logger.info('Using %s = %s' % (key, value))

    # Custom helpers.
    config.add_request_method(follow_subrequest)
    config.add_request_method(lambda request: {'id': request.prefixed_userid},
                              name='get_user_info')

    # Scan views.
    config.scan("cliquet.views")

    # Give sign of life.
    msg = "%(project_name)s %(project_version)s starting."
    logger.info(msg % settings)