Adding history configuration.truncate-history

Truncating request and response history to 20 entries by default,
allowing history.size to specify a discrete number of entries (positive),
unlimited entries (less than 0), or no history (zero).

2 files changed, 73 insertions, 0 deletions

diff --git a/jsonrpclib/history.py b/jsonrpclib/history.py
index f052baa..090f996 100644
--- a/jsonrpclib/history.py
+++ b/jsonrpclib/history.py
@@ -5,6 +5,7 @@ class History(object):
     each request cycle in order to keep it from clogging
     memory.
     """
+    size = 20
     requests = []
     responses = []
     _instance = None
@@ -16,10 +17,18 @@ class History(object):
         return cls._instance
 
     def add_response(self, response_obj):
+        if self.size == 0:
+            return
         self.responses.append(response_obj)
+        if self.size > 0:
+            self.responses = self.responses[0 - self.size:]
 
     def add_request(self, request_obj):
+        if self.size == 0:
+            return
         self.requests.append(request_obj)
+        if self.size > 0:
+            self.requests = self.requests[0 - self.size:]
 
     @property
     def request(self):
diff --git a/tests.py b/tests.py
index e241104..72d846d 100644
--- a/tests.py
+++ b/tests.py
@@ -36,6 +36,9 @@ from jsonrpclib.SimpleJSONRPCServer import SimpleJSONRPCServer
 from jsonrpclib.SimpleJSONRPCServer import SimpleJSONRPCRequestHandler
 
 
+ORIGINAL_HISTORY_SIZE = history.size
+
+
 def get_port(family=socket.AF_INET):
     sock = socket.socket(family, socket.SOCK_STREAM)
     sock.bind(("localhost", 0))
@@ -281,6 +284,11 @@ class InternalTests(unittest.TestCase):
     def setUp(self):
         self.port = get_port()
         self.server = server_set_up(addr=('', self.port))
+        self.addCleanup(self.cleanup)
+
+    def cleanup(self):
+        history.size = ORIGINAL_HISTORY_SIZE
+        history.clear()
 
     def get_client(self):
         return Server('http://localhost:%d' % self.port)
@@ -331,6 +339,62 @@ class InternalTests(unittest.TestCase):
         self.assertTrue(verify_request == request)
         self.assertTrue(verify_response == response)
 
+    def test_history_defaults_to_20(self):
+        client = self.get_client()
+        self.assertEqual(20, history.size)
+
+        for i in range(30):
+            client.namespace.sum(i, i)
+
+        self.assertEqual(20, len(history.requests))
+        self.assertEqual(20, len(history.responses))
+
+        verify_request = {
+            "jsonrpc": "2.0", "params": [29, 29],
+            "method": "namespace.sum"
+        }
+        verify_response = {"jsonrpc": "2.0", "result": 58}
+
+        # it should truncate to the *last* 20
+        request = json.loads(history.request)
+        response = json.loads(history.response)
+
+        verify_request["id"] = request["id"]
+        self.assertEqual(request, verify_request)
+
+        verify_response["id"] = request["id"]
+        self.assertEqual(response, verify_response)
+
+    def test_history_allows_configurable_size(self):
+        client = self.get_client()
+        history.size = 10
+
+        for i in range(30):
+            client.namespace.sum(i, i)
+
+        self.assertEqual(10, len(history.requests))
+        self.assertEqual(10, len(history.responses))
+
+    def test_history_allows_unlimited_size(self):
+        client = self.get_client()
+        history.size = -1
+
+        for i in range(40):
+            client.namespace.sum(i, i)
+
+        self.assertEqual(40, len(history.requests))
+        self.assertEqual(40, len(history.responses))
+
+    def test_history_can_be_disabled(self):
+        client = self.get_client()
+        history.size = 0
+
+        for i in range(40):
+            client.namespace.sum(i, i)
+
+        self.assertEqual(0, len(history.requests))
+        self.assertEqual(0, len(history.responses))
+
     def test_multicall_success(self):
         multicall = self.get_multicall_client()
         multicall.ping()