Make RESTful client a context manager and update example code (#37)

Author: jbonzo

polygon/rest/client.py

@@ -17,6 +17,15 @@ def __init__(self, auth_key: str):
         self._session = requests.Session()
         self._session.params["apiKey"] = self.auth_key
 
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *args):
+        self.close()
+
+    def close(self):
+        self._session.close()
+
     def _handle_response(self, response_type: str, endpoint: str, params: Dict[str, str]) -> Type[models.AnyDefinition]:
         resp: requests.Response = self._session.get(endpoint, params=params)
         if resp.status_code == 200:

rest-example.py

@@ -3,10 +3,12 @@
 
 def main():
     key = "your api key"
-    client = RESTClient(key)
 
-    resp = client.stocks_equities_daily_open_close("AAPL", "2018-03-02")
-    print(f"On: {resp.from_} Apple opened at {resp.open} and closed at {resp.close}")
+    # RESTClient can be used as a context manager to facilitate closing the underlying http session
+    # https://requests.readthedocs.io/en/master/user/advanced/#session-objects
+    with RESTClient(key) as client:
+        resp = client.stocks_equities_daily_open_close("AAPL", "2018-03-02")
+        print(f"On: {resp.from_} Apple opened at {resp.open} and closed at {resp.close}")
 
 
 if __name__ == '__main__':