"""
Store adapters to read data from magpie.
"""
from typing import TYPE_CHECKING
import requests
from beaker.cache import cache_region, cache_regions
from pyramid.httpexceptions import HTTPOk
from pyramid.settings import asbool
from magpie.api.schemas import ServicesAPI
from magpie.compat import LooseVersion
from magpie.db import get_connected_session
from magpie.models import Service as MagpieService
from magpie.services import invalidate_service
from magpie.utils import (
CONTENT_TYPE_JSON,
get_admin_cookies,
get_logger,
get_magpie_url,
get_settings,
get_twitcher_url
)
# WARNING:
# Twitcher available only when this module is imported from it.
# It is installed during tests for evaluation.
# Module 'magpie.adapter' should not be imported from 'magpie' package.
from twitcher.__version__ import __version__ as twitcher_version # noqa
from twitcher.exceptions import ServiceNotFound # noqa
if LooseVersion(twitcher_version) > LooseVersion("0.6.0"):
from twitcher.models import Service as TwitcherService # noqa # pylint: disable=E0611 # Twitcher >= 0.6.0
from twitcher.store import ServiceStoreInterface # noqa # pylint: disable=E0611 # Twitcher > 0.6.0
elif LooseVersion(twitcher_version) == LooseVersion("0.6.0"):
from twitcher.models import Service as TwitcherService # noqa # pylint: disable=E0611 # Twitcher >= 0.6.0
[docs]
class ServiceStoreInterface(object): # was removed on initial 0.6.0 version
def __init__(self, request):
self.request = request
else:
from twitcher.datatype import Service as TwitcherService # noqa # pylint: disable=E0611 # Twitcher <= 0.5.x
from twitcher.store import ServiceStoreInterface # noqa # pylint: disable=E0611 # Twitcher <= 0.5.x
if TYPE_CHECKING:
from typing import Any, List, NoReturn
from pyramid.request import Request
from magpie.typedefs import Str
[docs]
LOGGER = get_logger("TWITCHER|{}".format(__name__))
[docs]
class MagpieServiceStore(ServiceStoreInterface):
"""
Registry for OWS services.
Uses magpie to fetch service url and attributes.
"""
def __init__(self, request):
# type: (Request) -> None
super(MagpieServiceStore, self).__init__(request)
self.settings = get_settings(request)
self.session_factory = request.registry["dbsession_factory"]
self.magpie_url = get_magpie_url(request)
self.twitcher_url = get_twitcher_url(request)
self.twitcher_ssl_verify = asbool(self.settings.get("twitcher.ows_proxy_ssl_verify", True))
self.magpie_admin_token = get_admin_cookies(self.settings, self.twitcher_ssl_verify)
[docs]
def save_service(self, name, url, *args, **kwargs): # noqa: F811
# type: (Str, Str, *Any, **Any) -> NoReturn
"""
Store is read-only, use `Magpie` :term:`API` to add services.
.. note::
Multiple redundant parameters are applied to support different `Twitcher` versions.
- ``Twitcher <=0.5.x`` uses ``(service, *args, **kwargs)``
- ``Twitcher >=0.6.x`` uses ``(name, url, *args, **kwargs)``
- Some alternate interfaces also provided extra parameters at some point.
"""
msg = (
"MagpieAdapter does not support 'MagpieServiceStore.save_service' operation. "
"Use Magpie API or UI for service registration."
)
LOGGER.error(msg)
raise NotImplementedError(msg)
[docs]
def delete_service(self, name, *args, **kwargs): # noqa: F811
# type: (Str, *Any, **Any) -> NoReturn
"""
Store is read-only, use :mod:`Magpie` :term:`API` to delete services.
"""
msg = (
"MagpieAdapter does not support 'MagpieServiceStore.delete_service' operation. "
"Use Magpie API or UI for service removal."
)
LOGGER.error(msg)
raise NotImplementedError(msg)
[docs]
def list_services(self):
# type: () -> List[TwitcherService]
"""
Lists all services registered in `Magpie`.
"""
# obtain admin access since 'service_url' is only provided on admin routes
services = []
path = "{}{}".format(self.magpie_url, ServicesAPI.path)
resp = requests.get(path, cookies=self.magpie_admin_token, headers={"Accept": CONTENT_TYPE_JSON},
verify=self.twitcher_ssl_verify, timeout=5)
if resp.status_code != HTTPOk.code:
raise resp.raise_for_status()
json_body = resp.json()
for service_type in json_body["services"]:
for service in json_body["services"][service_type].values():
services.append(TwitcherService(url=service["service_url"],
name=service["service_name"],
type=service["service_type"]))
return services
@cache_region("service")
[docs]
def _fetch_by_name_cached(self, service_name):
# type: (Str) -> TwitcherService
"""
Cache this method with :py:mod:`beaker` based on the provided caching key parameters.
If the cache is not hit (expired timeout or new key entry), calls :meth:`fetch_by_name` to retrieve the actual
:class:`twitcher.datatype.Service` definition. Otherwise, returns the cached item to avoid SQL queries.
.. note::
Function arguments are required to generate caching keys by which cached elements will be retrieved.
.. note::
Method :meth:`fetch_by_name` gets triggered by :meth:`twitcher.owsproxy.owsproxy_view` after successful
validation of granted access for :term:`Logged User` to the service / resources following call to
:meth:`magpie.adapter.magpieowssecurity.MagpieOWSSecurity.check_request` in order to send and retrieve
the actual response of that proxied service and forward it back to the requesting user.
Caching helps greatly reduce recurrent SQL queries to convert `Twitcher` to `Magpie` service.
.. seealso::
- :meth:`magpie.adapter.magpieowssecurity.MagpieOWSSecurity.get_service`
- :meth:`magpie.adapter.magpieservice.MagpieServiceStore.fetch_by_name`
"""
session = get_connected_session(self.request)
service = MagpieService.by_service_name(service_name, db_session=session)
if service is None:
raise ServiceNotFound("Service name not found.")
service_data = dict(
url=service.url,
name=service.resource_name,
type=service.type,
verify=self.twitcher_ssl_verify
)
if LooseVersion(twitcher_version) >= LooseVersion("0.6.0"):
service_data["_verify"] = int(service_data.pop("verify")) # parameter renamed and different type
service_data["id"] = service.resource_id
service_data["purl"] = "{}/{}".format(self.twitcher_url, service.resource_name)
service_data["auth"] = "magpie"
return TwitcherService(**service_data)
[docs]
def fetch_by_name(self, name):
# type: (Str) -> TwitcherService
"""
Gets :class:`twitcher.datatype.Service` corresponding to :class:`magpie.models.Service` by ``name``.
"""
# make sure the cache is invalidated to retrieve 'fresh' service from database if requested or cache disabled
if "service" not in cache_regions:
cache_regions["service"] = {"enabled": False}
if self.request.headers.get("Cache-Control") == "no-cache":
invalidate_service(name)
service = self._fetch_by_name_cached(name)
return service
[docs]
def fetch_by_url(self, url):
# type: (Str) -> TwitcherService
"""
Gets service for given ``url`` from mongodb storage.
"""
services = self.list_services()
for service in services:
if service.url == url:
return service
raise ServiceNotFound
[docs]
def clear_services(self):
# type: () -> NoReturn
"""
Magpie store is read-only, use magpie api to delete services.
"""
raise NotImplementedError
