Try to reuse the HttpClient between requests by default

README.md

@@ -113,7 +113,8 @@ production use, but `debug` is also available for more verbosity.
 
 There are a few options for enabling it:
 
-1. Set the environment variable `STRIPE_LOG` to the value `debug` or `info`
+1. Set the environment variable `STRIPE_LOG` to the value `debug`, `info` or
+   `warning`
 
    ```
    $ export STRIPE_LOG=debug

stripe/api_requestor.py

@@ -83,16 +83,28 @@ def __init__(
         self.api_version = api_version or stripe.api_version
         self.stripe_account = account
 
+        self._default_proxy = None
+
         from stripe import verify_ssl_certs as verify
         from stripe import proxy
 
-        self._client = (
-            client
-            or stripe.default_http_client
-            or http_client.new_default_http_client(
+        if client:
+            self._client = client
+        elif stripe.default_http_client:
+            self._client = stripe.default_http_client
+            if proxy != self._default_proxy:
+                util.log_warning(
+                    "stripe.proxy was updated after sending a request - this is a no-op. To use a different proxy, set stripe.default_http_client to a new client configured with the proxy."
+                )
+        else:
+            # If the stripe.default_http_client has not been set by the user
+            # yet, we'll set it here. This way, we aren't creating a new
+            # HttpClient for every request.
+            stripe.default_http_client = http_client.new_default_http_client(
                 verify_ssl_certs=verify, proxy=proxy
             )
-        )
+            self._client = stripe.default_http_client
+            self._default_proxy = proxy
 
         self._last_request_metrics = None
 

stripe/util.py

@@ -20,6 +20,7 @@
     "io",
     "parse_qsl",
     "utf8",
+    "log_warning",
     "log_info",
     "log_debug",
     "dashboard_link",
@@ -41,9 +42,9 @@ def is_appengine_dev():
 
 
 def _console_log_level():
-    if stripe.log in ["debug", "info"]:
+    if stripe.log in ["debug", "info", "warning"]:
         return stripe.log
-    elif STRIPE_LOG in ["debug", "info"]:
+    elif STRIPE_LOG in ["debug", "info", "warning"]:
         return STRIPE_LOG
     else:
         return None
@@ -63,6 +64,13 @@ def log_info(message, **params):
     logger.info(msg)
 
 
+def log_warning(message, **params):
+    msg = logfmt(dict(message=message, **params))
+    if _console_log_level() in ["debug", "info", "warning"]:
+        print(msg, file=sys.stderr)
+    logger.warning(msg)
+
+
 def _test_or_live_environment():
     if stripe.api_key is None:
         return

tests/test_api_requestor.py

@@ -231,14 +231,17 @@ def setup_stripe(self):
         orig_attrs = {
             "api_key": stripe.api_key,
             "api_version": stripe.api_version,
+            "default_http_client": stripe.default_http_client,
             "enable_telemetry": stripe.enable_telemetry,
         }
         stripe.api_key = "sk_test_123"
         stripe.api_version = "2017-12-14"
+        stripe.default_http_client = None
         stripe.enable_telemetry = False
         yield
         stripe.api_key = orig_attrs["api_key"]
         stripe.api_version = orig_attrs["api_version"]
+        stripe.default_http_client = orig_attrs["default_http_client"]
         stripe.enable_telemetry = orig_attrs["enable_telemetry"]
 
     @pytest.fixture
@@ -485,6 +488,25 @@ def test_uses_instance_account(
             ),
         )
 
+    def test_sets_default_http_client(self, http_client):
+        assert not stripe.default_http_client
+
+        stripe.api_requestor.APIRequestor(client=http_client)
+
+        # default_http_client is not populated if a client is provided
+        assert not stripe.default_http_client
+
+        stripe.api_requestor.APIRequestor()
+
+        # default_http_client is set when no client is specified
+        assert stripe.default_http_client
+
+        new_default_client = stripe.default_http_client
+        stripe.api_requestor.APIRequestor()
+
+        # the newly created client is reused
+        assert stripe.default_http_client == new_default_client
+
     def test_uses_app_info(self, requestor, mock_response, check_call):
         try:
             old = stripe.app_info

tests/test_integration.py

@@ -0,0 +1,128 @@
+import sys
+from threading import Thread
+import json
+
+import stripe
+import pytest
+
+if sys.version_info[0] < 3:
+    from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
+else:
+    from http.server import BaseHTTPRequestHandler, HTTPServer
+
+
+class TestIntegration(object):
+    @pytest.fixture(autouse=True)
+    def close_mock_server(self):
+        yield
+        if self.mock_server:
+            self.mock_server.shutdown()
+            self.mock_server.server_close()
+            self.mock_server_thread.join()
+
+    @pytest.fixture(autouse=True)
+    def setup_stripe(self):
+        orig_attrs = {
+            "api_base": stripe.api_base,
+            "api_key": stripe.api_key,
+            "default_http_client": stripe.default_http_client,
+            "log": stripe.log,
+            "proxy": stripe.proxy,
+        }
+        stripe.api_base = "http://localhost:12111"  # stripe-mock
+        stripe.api_key = "sk_test_123"
+        stripe.default_http_client = None
+        stripe.log = "warning"
+        stripe.proxy = None
+        yield
+        stripe.api_base = orig_attrs["api_base"]
+        stripe.api_key = orig_attrs["api_key"]
+        stripe.default_http_client = orig_attrs["default_http_client"]
+        stripe.log = orig_attrs["log"]
+        stripe.proxy = orig_attrs["proxy"]
+
+    def setup_mock_server(self, handler):
+        # Configure mock server.
+        # Passing 0 as the port will cause a random free port to be chosen.
+        self.mock_server = HTTPServer(("localhost", 0), handler)
+        _, self.mock_server_port = self.mock_server.server_address
+
+        # Start running mock server in a separate thread.
+        # Daemon threads automatically shut down when the main process exits.
+        self.mock_server_thread = Thread(target=self.mock_server.serve_forever)
+        self.mock_server_thread.setDaemon(True)
+        self.mock_server_thread.start()
+
+    def test_hits_api_base(self):
+        class MockServerRequestHandler(BaseHTTPRequestHandler):
+            num_requests = 0
+
+            def do_GET(self):
+                self.__class__.num_requests += 1
+
+                self.send_response(200)
+                self.send_header(
+                    "Content-Type", "application/json; charset=utf-8"
+                )
+                self.end_headers()
+                self.wfile.write(json.dumps({}).encode("utf-8"))
+                return
+
+        self.setup_mock_server(MockServerRequestHandler)
+
+        stripe.api_base = "http://localhost:%s" % self.mock_server_port
+        stripe.Balance.retrieve()
+        assert MockServerRequestHandler.num_requests == 1
+
+    def test_hits_proxy_through_default_http_client(self, mocker):
+        class MockServerRequestHandler(BaseHTTPRequestHandler):
+            num_requests = 0
+
+            def do_GET(self):
+                self.__class__.num_requests += 1
+
+                self.send_response(200)
+                self.send_header(
+                    "Content-Type", "application/json; charset=utf-8"
+                )
+                self.end_headers()
+                self.wfile.write(json.dumps({}).encode("utf-8"))
+                return
+
+        self.setup_mock_server(MockServerRequestHandler)
+        logger_mock = mocker.patch("stripe.util.log_warning")
+
+        stripe.proxy = "http://localhost:%s" % self.mock_server_port
+        stripe.Balance.retrieve()
+        assert MockServerRequestHandler.num_requests == 1
+
+        stripe.proxy = "http://bad-url"
+        logger_mock.assert_not_called()
+        stripe.Balance.retrieve()
+        logger_mock.assert_called_with(
+            "stripe.proxy was updated after sending a request - this is a no-op. To use a different proxy, set stripe.default_http_client to a new client configured with the proxy."
+        )
+        assert MockServerRequestHandler.num_requests == 2
+
+    def test_hits_proxy_through_custom_client(self):
+        class MockServerRequestHandler(BaseHTTPRequestHandler):
+            num_requests = 0
+
+            def do_GET(self):
+                self.__class__.num_requests += 1
+
+                self.send_response(200)
+                self.send_header(
+                    "Content-Type", "application/json; charset=utf-8"
+                )
+                self.end_headers()
+                self.wfile.write(json.dumps({}).encode("utf-8"))
+                return
+
+        self.setup_mock_server(MockServerRequestHandler)
+
+        stripe.default_http_client = stripe.http_client.new_default_http_client(
+            proxy="http://localhost:%s" % self.mock_server_port
+        )
+        stripe.Balance.retrieve()
+        assert MockServerRequestHandler.num_requests == 1

tests/test_util.py

@@ -71,6 +71,8 @@ def test_log_debug(self, mocker):
         # (STRIPE_LOG, stripe.log): should_output?
         test_cases = [
             LogTestCase(env=None, flag=None, should_output=False),
+            LogTestCase(env="warning", flag=None, should_output=False),
+            LogTestCase(env=None, flag="warning", should_output=False),
             LogTestCase(env=None, flag="debug", should_output=True),
             LogTestCase(env=None, flag="info", should_output=False),
             LogTestCase(env="debug", flag=None, should_output=True),
@@ -91,6 +93,8 @@ def test_log_info(self, mocker):
         # (STRIPE_LOG, stripe.log): should_output?
         test_cases = [
             LogTestCase(env=None, flag=None, should_output=False),
+            LogTestCase(env="warning", flag=None, should_output=False),
+            LogTestCase(env=None, flag="warning", should_output=False),
             LogTestCase(env=None, flag="debug", should_output=True),
             LogTestCase(env=None, flag="info", should_output=True),
             LogTestCase(env="debug", flag=None, should_output=True),
@@ -107,6 +111,28 @@ def test_log_info(self, mocker):
             mocker=mocker,
         )
 
+    def test_log_warning(self, mocker):
+        # (STRIPE_LOG, stripe.log): should_output?
+        test_cases = [
+            LogTestCase(env=None, flag=None, should_output=False),
+            LogTestCase(env="warning", flag=None, should_output=True),
+            LogTestCase(env=None, flag="warning", should_output=True),
+            LogTestCase(env=None, flag="debug", should_output=True),
+            LogTestCase(env=None, flag="info", should_output=True),
+            LogTestCase(env="debug", flag=None, should_output=True),
+            LogTestCase(env="debug", flag="debug", should_output=True),
+            LogTestCase(env="debug", flag="info", should_output=True),
+            LogTestCase(env="info", flag=None, should_output=True),
+            LogTestCase(env="info", flag="debug", should_output=True),
+            LogTestCase(env="info", flag="info", should_output=True),
+        ]
+        self.log_test_loop(
+            test_cases,
+            logging_func=util.log_warning,
+            logger_name="stripe.util.logger.warning",
+            mocker=mocker,
+        )
+
     def test_logfmt(self):
         cases = [
             FmtTestCase(