Add generic support for client context params

botocore/args.py

@@ -266,6 +266,7 @@ def compute_client_args(
                 disable_request_compression=(
                     client_config.disable_request_compression
                 ),
+                client_context_params=client_config.client_context_params,
             )
         self._compute_retry_config(config_kwargs)
         self._compute_connect_timeout(config_kwargs)
@@ -641,14 +642,16 @@ def _build_endpoint_resolver(
             client_endpoint_url=endpoint_url,
             legacy_endpoint_url=endpoint.host,
         )
-        # botocore does not support client context parameters generically
-        # for every service. Instead, the s3 config section entries are
-        # available as client context parameters. In the future, endpoint
-        # rulesets of services other than s3/s3control may require client
-        # context parameters.
-        client_context = (
-            s3_config_raw if self._is_s3_service(service_name_raw) else {}
-        )
+        # Client context params for s3 conflict with the available settings
+        # in the `s3` parameter on the `Config` object. If the same parameter
+        # is set in both places, the value in the `s3` parameter takes priority.
+        if client_config is not None:
+            client_context = client_config.client_context_params or {}
+        else:
+            client_context = {}
+        if self._is_s3_service(service_name_raw):
+            client_context.update(s3_config_raw)
+
         sig_version = (
             client_config.signature_version
             if client_config is not None

botocore/config.py

@@ -219,6 +219,15 @@ class Config:
     :param disable_request_compression: Disables request body compression if
         set to True.
 
+        Defaults to None.
+
+    :type client_context_params: dict
+    :param client_context_params: A dictionary of parameters specific to
+        individual services. If available, valid parameters can be found in the
+        ``Client Context Parameters`` section of the service's client homepage.
+        Invalid parameters or ones that are not used by the specified service
+        will be ignored.
+
         Defaults to None.
     """
 
@@ -247,6 +256,7 @@ class Config:
             ('tcp_keepalive', None),
             ('request_min_compression_size_bytes', None),
             ('disable_request_compression', None),
+            ('client_context_params', None),
         ]
     )
 

botocore/docs/client.py

@@ -12,6 +12,7 @@
 # language governing permissions and limitations under the License.
 import os
 
+from botocore import xform_name
 from botocore.compat import OrderedDict
 from botocore.docs.bcdoc.restdoc import DocumentStructure
 from botocore.docs.example import ResponseExampleDocumenter
@@ -399,3 +400,56 @@ def _add_response_params(self, section, shape):
             shape,
             include=[self._GENERIC_ERROR_SHAPE],
         )
+
+
+class ClientContextParamsDocumenter:
+    _CONFIG_GUIDE_LINK = (
+        'https://boto3.amazonaws.com/'
+        'v1/documentation/api/latest/guide/configuration.html'
+    )
+
+    OMITTED_CONTEXT_PARAMS = {
+        's3': (
+            'Accelerate',
+            'DisableMultiRegionAccessPoints',
+            'ForcePathStyle',
+            'UseArnRegion',
+        ),
+        's3control': ('UseArnRegion',),
+    }
+
+    def __init__(self, service_name, context_params):
+        self._service_name = service_name
+        self._context_params = context_params
+
+    def document_context_params(self, section):
+        self._add_title(section)
+        self._add_overview(section)
+        self._add_context_params_list(section)
+
+    def _add_title(self, section):
+        section.style.h2('Client Context Parameters')
+
+    def _add_overview(self, section):
+        section.style.new_line()
+        section.write(
+            'Client context parameters are configurable on a client '
+            'instance via the ``client_context_params`` parameter in the '
+            '``Config`` object. For more detailed instructions and examples '
+            'on the exact usage of context params see the '
+        )
+        section.style.external_link(
+            title='configuration guide',
+            link=self._CONFIG_GUIDE_LINK,
+        )
+        section.write('.')
+        section.style.new_line()
+
+    def _add_context_params_list(self, section):
+        section.style.new_line()
+        sn = f'``{self._service_name}``'
+        section.writeln(f'The available {sn} client context params are:')
+        for param in self._context_params:
+            section.style.new_line()
+            name = f'``{xform_name(param.name)}``'
+            section.write(f'* {name} ({param.type}) - {param.documentation}')

botocore/docs/service.py

@@ -11,7 +11,11 @@
 # ANY KIND, either express or implied. See the License for the specific
 # language governing permissions and limitations under the License.
 from botocore.docs.bcdoc.restdoc import DocumentStructure
-from botocore.docs.client import ClientDocumenter, ClientExceptionsDocumenter
+from botocore.docs.client import (
+    ClientContextParamsDocumenter,
+    ClientDocumenter,
+    ClientExceptionsDocumenter,
+)
 from botocore.docs.paginator import PaginatorDocumenter
 from botocore.docs.waiter import WaiterDocumenter
 from botocore.exceptions import DataNotFoundError
@@ -37,6 +41,7 @@ def __init__(self, service_name, session, root_docs_path):
             'client-exceptions',
             'paginator-api',
             'waiter-api',
+            'client-context-params',
         ]
 
     def document_service(self):
@@ -52,6 +57,10 @@ def document_service(self):
         self.client_exceptions(doc_structure.get_section('client-exceptions'))
         self.paginator_api(doc_structure.get_section('paginator-api'))
         self.waiter_api(doc_structure.get_section('waiter-api'))
+        context_params_section = doc_structure.get_section(
+            'client-context-params'
+        )
+        self.client_context_params(context_params_section)
         return doc_structure.flush_structure()
 
     def title(self, section):
@@ -108,3 +117,17 @@ def get_examples(self, service_name, api_version=None):
             service_name, 'examples-1', api_version
         )
         return examples['examples']
+
+    def client_context_params(self, section):
+        omitted_params = ClientContextParamsDocumenter.OMITTED_CONTEXT_PARAMS
+        params_to_omit = omitted_params.get(self._service_name, [])
+        service_model = self._client.meta.service_model
+        raw_context_params = service_model.client_context_parameters
+        context_params = [
+            p for p in raw_context_params if p.name not in params_to_omit
+        ]
+        if context_params:
+            context_param_documenter = ClientContextParamsDocumenter(
+                self._service_name, context_params
+            )
+            context_param_documenter.document_context_params(section)

tests/functional/docs/test_s3.py

@@ -10,6 +10,8 @@
 # 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.
+from botocore import xform_name
+from botocore.docs.client import ClientContextParamsDocumenter
 from botocore.docs.service import ServiceDocumenter
 from tests.functional.docs import BaseDocsFunctionalTest
 
@@ -78,3 +80,23 @@ def test_copy_source_param_docs_also_modified(self):
         self.assert_contains_line(
             "You can also provide this value as a dictionary", param_docs
         )
+
+    def test_s3_context_params_omitted(self):
+        omitted_params = ClientContextParamsDocumenter.OMITTED_CONTEXT_PARAMS
+        s3_omitted_params = omitted_params['s3']
+        content = ServiceDocumenter(
+            's3', self._session, self.root_services_path
+        ).document_service()
+        for param in s3_omitted_params:
+            param_name = f'``{xform_name(param)}``'
+            self.assert_not_contains_line(param_name, content)
+
+    def test_s3control_context_params_omitted(self):
+        omitted_params = ClientContextParamsDocumenter.OMITTED_CONTEXT_PARAMS
+        s3control_omitted_params = omitted_params['s3control']
+        content = ServiceDocumenter(
+            's3control', self._session, self.root_services_path
+        ).document_service()
+        for param in s3control_omitted_params:
+            param_name = f'``{xform_name(param)}``'
+            self.assert_not_contains_line(param_name, content)