#188067891 : Added suppor to refresh connection pool on ConnectionErr…

…or. (#24)

* Added suppor to refresh connection pool on ConnectionError.

* Log message on ConnectionError and Attempt to reestablish connection pool.

moesifapi/configuration.py

@@ -12,7 +12,7 @@ class Configuration(object):
 
     # Your Application Id for authentication/authorization
     application_id = 'SET_ME'
-    version = 'moesifapi-python/1.5.0'
+    version = 'moesifapi-python/1.5.1'
 
     pool_connections = 10
     pool_maxsize = 10

moesifapi/http/requests_client.py

@@ -12,6 +12,27 @@
 from .http_client import HttpClient
 from .http_response import HttpResponse
 from .http_method_enum import HttpMethodEnum
+from requests.packages.urllib3.util.retry import Retry
+
+
+# Decorator to refresh connection pool on ConnectionError
+def refresh_session(func):
+    # Wrap function with retry once on ConnectionError
+    def wrapper(self, *args, **kwargs):
+        try:
+            result = func(self, *args, **kwargs)
+        except requests.exceptions.ConnectionError as e:
+            print(f"ConnectionError: Attempt to reestablish the connection")
+            # Attempt to reestablish the connection
+            self.__refresh_connection_pool__()
+
+            # retry
+            result = func(self, *args, **kwargs)
+
+        return result
+
+    return wrapper
+
 
 class RequestsClient(HttpClient):
 
@@ -20,13 +41,32 @@ class RequestsClient(HttpClient):
     """
 
     # connection pool here
+    def __create_connection_pool__(self):
+        retry_strategy = Retry(
+            total=3,
+            backoff_factor=1,
+            status_forcelist=[429, 500, 502, 503, 504],
+        )
 
-    def __init__(self):
         self.session = requests.Session()
-        self.adapter = HTTPAdapter(pool_connections=Configuration.pool_connections, pool_maxsize=Configuration.pool_maxsize)
+        self.adapter = HTTPAdapter(
+            max_retries=retry_strategy,
+            pool_connections=Configuration.pool_connections,
+            pool_maxsize=Configuration.pool_maxsize
+        )
         self.session.mount('http://', self.adapter)
         self.session.mount('https://', self.adapter)
 
+    def __refresh_connection_pool__(self):
+        # Attempt to reestablish the connection.
+        # clear closes all open connections - leaves in-flight connections, but it will not be re-used after completion.
+        # It automatically opens a new ConnectionPool if no open connections exist for the request.
+        self.adapter.poolmanager.clear()
+
+    def __init__(self):
+        self.__create_connection_pool__()
+
+    @refresh_session
     def execute_as_string(self, request):
         """Execute a given HttpRequest to get a string response back
        
@@ -40,7 +80,7 @@ def execute_as_string(self, request):
         auth = None
 
         if request.username or request.password:
-            auth=(request.username, request.password)
+            auth = (request.username, request.password)
 
         # connection pool to make request
         response = self.session.request(HttpMethodEnum.to_string(request.http_method),
@@ -52,7 +92,8 @@ def execute_as_string(self, request):
                                         auth=auth)
 
         return self.convert_response(response, False)
-
+
+    @refresh_session
     def execute_as_binary(self, request):
         """Execute a given HttpRequest to get a binary response back
        
@@ -66,7 +107,7 @@ def execute_as_binary(self, request):
         auth = None
 
         if request.username or request.password:
-            auth=(request.username, request.password)
+            auth = (request.username, request.password)
 
         response = requests.request(HttpMethodEnum.to_string(request.http_method), 
                                     request.query_url, 
@@ -92,4 +133,4 @@ def convert_response(self, response, binary):
         if binary == True:
             return HttpResponse(response.status_code, response.headers, response.content)
         else:
-            return HttpResponse(response.status_code, response.headers, response.text)
+            return HttpResponse(response.status_code, response.headers, response.text)

setup.py

@@ -28,7 +28,7 @@
     # Versions should comply with PEP440.  For a discussion on single-sourcing
     # the version across setup.py and the project code, see
     # https://packaging.python.org/en/latest/single_source_version.html
-    version='1.5.0',
+    version='1.5.1',
 
     description='Moesif API Lib for Python',
     long_description=long_description,