Merge pull request #24 from gis-ops/fix#22

Fix#22

routingpy/client_base.py

@@ -0,0 +1,217 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2021 GIS OPS UG
+#
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+#
+"""
+Core client functionality, common across all routers.
+"""
+
+
+from routingpy.__version__ import __version__
+
+from abc import ABCMeta, abstractmethod
+from datetime import timedelta
+import requests
+from urllib.parse import urlencode
+
+
+_DEFAULT_USER_AGENT = "routingpy/v{}".format(__version__)
+_RETRIABLE_STATUSES = set([503])
+
+
+class options(object):
+    """
+    Contains default configuration options for all routers, e.g. `timeout` and `proxies`. Each router can take the same
+    configuration values, which will override the values set in `options` object.
+
+    Example for overriding default values for `user_agent` and proxies:
+
+    >>> from routingpy.routers import options
+    >>> from routingpy.routers import MapboxValhalla
+    >>> options.default_user_agent = 'amazing_routing_app'
+    >>> options.default_proxies = {'https': '129.125.12.0'}
+    >>> router = MapboxValhalla(my_key)
+    >>> print(router.headers)
+    {'User-Agent': 'amazing_routing_app', 'Content-Type': 'application/json'}
+    >>> print(router.proxies)
+    {'https': '129.125.12.0'}
+
+    Attributes:
+        self.default_timeout:
+            Combined connect and read timeout for HTTP requests, in
+            seconds. Specify "None" for no timeout. Integer.
+
+        self.default_retry_timeout:
+            Timeout across multiple retriable requests, in
+            seconds. Integer.
+
+        self.default_retry_over_query_limit:
+            If True, client will not raise an exception
+            on HTTP 429, but instead jitter a sleeping timer to pause between
+            requests until HTTP 200 or retry_timeout is reached. Boolean.
+
+        self.default_skip_api_error:
+            Continue with batch processing if a :class:`routingpy.exceptions.RouterApiError` is
+            encountered (e.g. no route found). If False, processing will discontinue and raise an error. Boolean.
+
+        self.default_user_agent:
+            User-Agent to send with the requests to routing API. String.
+
+        self.default_proxies:
+            Proxies passed to the requests library. Dictionary.
+    """
+
+    default_timeout = 60
+    default_retry_timeout = 60
+    default_retry_over_query_limit = True
+    default_skip_api_error = False
+    default_user_agent = _DEFAULT_USER_AGENT
+    default_proxies = None
+
+
+# To avoid trouble when respecting timeout for individual routers (i.e. can't be None, since that's no timeout)
+DEFAULT = type("object", (object,), {"__repr__": lambda self: "DEFAULT"})()
+
+
+class BaseClient(metaclass=ABCMeta):
+    """Abstract base class every client inherits from. Authentication is handled in each subclass."""
+
+    def __init__(
+        self,
+        base_url,
+        user_agent=None,
+        timeout=DEFAULT,
+        retry_timeout=None,
+        retry_over_query_limit=None,
+        skip_api_error=None,
+        **kwargs
+    ):
+        """
+        :param base_url: The base URL for the request. All routers must provide a default.
+            Should not have a trailing slash.
+        :type base_url: string
+
+        :param user_agent: User-Agent to send with the requests to routing API.
+            Overrides ``options.default_user_agent``.
+        :type user_agent: string
+
+        :param timeout: Combined connect and read timeout for HTTP requests, in
+            seconds. Specify "None" for no timeout.
+        :type timeout: int
+
+        :param retry_timeout: Timeout across multiple retriable requests, in
+            seconds.
+        :type retry_timeout: int
+
+        :param retry_over_query_limit: If True, client will not raise an exception
+            on HTTP 429, but instead jitter a sleeping timer to pause between
+            requests until HTTP 200 or retry_timeout is reached.
+        :type retry_over_query_limit: bool
+
+        :param skip_api_error: Continue with batch processing if a :class:`routingpy.exceptions.RouterApiError` is
+            encountered (e.g. no route found). If False, processing will discontinue and raise an error. Default False.
+        :type skip_api_error: bool
+
+        :param **kwargs: Additional keyword arguments for the `requests library <https://docs.python-requests.org/en/master/api/#requests.request>`_
+        :type **kwargs: dict
+        """
+        self.base_url = base_url
+
+        self.retry_over_query_limit = (
+            retry_over_query_limit
+            if retry_over_query_limit is False
+            else options.default_retry_over_query_limit
+        )
+        self.retry_timeout = timedelta(seconds=retry_timeout or options.default_retry_timeout)
+
+        self.skip_api_error = skip_api_error or options.default_skip_api_error
+
+        self.headers = {
+            "User-Agent": user_agent or options.default_user_agent,
+            "Content-Type": "application/json",
+        }
+
+        self.timeout = timeout if timeout != DEFAULT else options.default_timeout
+
+        self.kwargs = kwargs
+
+        self._req = None
+
+    @abstractmethod
+    def _request(
+        self,
+        url,
+        get_params={},
+        post_params=None,
+        first_request_time=None,
+        retry_counter=0,
+        dry_run=None,
+    ):
+        """Performs HTTP GET/POST with credentials, returning the body as
+        JSON.
+
+        :param url: URL path for the request. Should begin with a slash.
+        :type url: string
+
+        :param get_params: HTTP GET parameters.
+        :type get_params: dict or list of tuples
+
+        :param post_params: HTTP POST parameters. Only specified by calling method.
+        :type post_params: dict
+
+        :param first_request_time: The time of the first request (None if no
+            retries have occurred).
+        :type first_request_time: :class:`datetime.datetime`
+
+        :param retry_counter: The number of this retry, or zero for first attempt.
+        :type retry_counter: int
+
+        :param dry_run: If 'true', only prints URL and parameters. 'true' or 'false'.
+        :type dry_run: string
+
+        :raises routingpy.exceptions.RouterApiError: when the API returns an error due to faulty configuration.
+        :raises routingpy.exceptions.RouterServerError: when the API returns a server error.
+        :raises routingpy.exceptions.RouterError: when anything else happened while requesting.
+        :raises routingpy.exceptions.JSONParseError: when the JSON response can't be parsed.
+        :raises routingpy.exceptions.Timeout: when the request timed out.
+        :raises routingpy.exceptions.TransportError: when something went wrong while trying to
+            execute a request.
+
+        :returns: raw JSON response.
+        :rtype: dict
+        """
+        pass
+
+    @staticmethod
+    def _generate_auth_url(path, params):
+        """Returns the path and query string portion of the request URL, first
+        adding any necessary parameters.
+
+        :param path: The path portion of the URL.
+        :type path: string
+
+        :param params: URL parameters.
+        :type params: dict or list of key/value tuples
+
+        :rtype: string
+
+        """
+
+        if isinstance(params, dict):
+            params = sorted(dict(**params).items())
+        elif isinstance(params, (list, tuple)):
+            params = params
+
+        return path + "?" + requests.utils.unquote_unreserved(urlencode(params))