Allow start==end in stream_insert_context, if no data was provided.

nilmdb/client/client.py

@@ -449,7 +449,7 @@ class StreamInserter(object):
             self._interval_start = end_ts
 
         # Double check endpoints
-        if start_ts is None or end_ts is None:
+        if (start_ts is None or end_ts is None) or (start_ts == end_ts):
             # If the block has no non-comment lines, it's OK
             try:
                 self._get_first_noncomment(block)

nilmdb/client/numpyclient.py

@@ -134,16 +134,8 @@ class StreamInserterNumpy(nilmdb.client.client.StreamInserter):
         contiguous interval and may be None.  'dtype' is the Numpy
         dtype for this stream.
         """
-        self.last_response = None
-
+        super(StreamInserterNumpy, self).__init__(client, path, start, end)
         self._dtype = dtype
-        self._client = client
-        self._path = path
-
-        # Start and end for the overall contiguous interval we're
-        # filling
-        self._interval_start = start
-        self._interval_end = end
 
         # Max rows to send at once
         self._max_rows = self._max_data // self._dtype.itemsize
@@ -251,9 +243,12 @@ class StreamInserterNumpy(nilmdb.client.client.StreamInserter):
             # Next block continues where this one ended
             self._interval_start = end_ts
 
-        # If we have no endpoints, it's because we had no data to send.
-        if start_ts is None or end_ts is None:
-            return
+        # If we have no endpoints, or equal endpoints, it's OK as long
+        # as there's no data to send
+        if (start_ts is None or end_ts is None) or (start_ts == end_ts):
+            if len(array) == 0:
+                return
+            raise ClientError("have data to send, but invalid start/end times")
 
         # Send it
         data = array.tostring()

tests/test_client.py

@@ -620,6 +620,10 @@ class TestClient(object):
         with client.stream_insert_context("/empty/test", end = 950):
             pass
 
+        # Equal start and end is OK as long as there's no data
+        with client.stream_insert_context("/empty/test", start=9, end=9):
+            pass
+
         # Try various things that might cause problems
         with client.stream_insert_context("/empty/test", 1000, 1050) as ctx:
             ctx.finalize() # inserts [1000, 1050]

tests/test_numpyclient.py

@@ -309,6 +309,22 @@ class TestNumpyClient(object):
         with client.stream_insert_numpy_context("/empty/test", end = 950):
             pass
 
+        # Equal start and end is OK as long as there's no data
+        with assert_raises(ClientError) as e:
+            with client.stream_insert_numpy_context("/empty/test",
+                                                    start=9, end=9) as ctx:
+                ctx.insert([[9, 9]])
+                ctx.finalize()
+        in_("have data to send, but invalid start/end times", str(e.exception))
+
+        with client.stream_insert_numpy_context("/empty/test",
+                                                start=9, end=9) as ctx:
+            pass
+
+        # reusing a context object is bad
+        with assert_raises(Exception) as e:
+            ctx.insert([[9, 9]])
+
         # Try various things that might cause problems
         with client.stream_insert_numpy_context("/empty/test",
                                                 1000, 1050) as ctx: