chore(line_protocol): update repr value of floats to properly handle …

…precision. Closes #488

influxdb/line_protocol.py

@@ -113,7 +113,7 @@ def _escape_value(value):
         return str(value) + 'i'
 
     if _is_float(value):
-        return repr(value)
+        return repr(float(value))
 
     return str(value)
 

influxdb/tests/test_line_protocol.py

@@ -6,10 +6,12 @@
 from __future__ import print_function
 from __future__ import unicode_literals
 
-from datetime import datetime
 import unittest
-from pytz import UTC, timezone
 
+from datetime import datetime
+from decimal import Decimal
+
+from pytz import UTC, timezone
 from influxdb import line_protocol
 
 
@@ -166,3 +168,20 @@ def test_float_with_long_decimal_fraction(self):
             line_protocol.make_lines(data),
             'test float_val=1.0000000000000009\n'
         )
+
+    def test_float_with_long_decimal_fraction_as_type_decimal(self):
+        """Ensure precision is preserved when casting Decimal into strings."""
+        data = {
+            "points": [
+                {
+                    "measurement": "test",
+                    "fields": {
+                        "float_val": Decimal(1.0000000000000009),
+                    }
+                }
+            ]
+        }
+        self.assertEqual(
+            line_protocol.make_lines(data),
+            'test float_val=1.0000000000000009\n'
+        )