Merge pull request #6 from brian-brazil/quantile

Disallow 'quantile' as a label to Summary.

Author: brian-brazil

prometheus_client/__init__.py

@@ -136,6 +136,8 @@ def init(name, documentation, labelnames=(), namespace='', subsystem='', registr
           raise ValueError('Invalid label metric name: ' + l)
         if _RESERVED_METRIC_LABEL_NAME_RE.match(l):
           raise ValueError('Reserved label metric name: ' + l)
+        if l in cls._reserved_labelnames:
+          raise ValueError('Reserved label metric name: ' + l)
       collector = _LabelWrapper(cls, labelnames)
     else:
       collector = cls()
@@ -165,6 +167,7 @@ def collect():
 @_MetricWrapper
 class Counter(object):
   _type = 'counter'
+  _reserved_labelnames = []
   def __init__(self):
     self._value = 0.0
     self._lock = Lock()
@@ -205,6 +208,7 @@ def _samples(self):
 @_MetricWrapper
 class Gauge(object):
   _type = 'gauge'
+  _reserved_labelnames = []
   def __init__(self):
     self._value = 0.0
     self._lock = Lock()
@@ -257,6 +261,7 @@ def _samples(self):
 @_MetricWrapper
 class Summary(object):
   _type = 'summary'
+  _reserved_labelnames = ['quantile']
   def __init__(self):
     self._count = 0.0
     self._sum = 0.0

tests/test_client.py

@@ -143,6 +143,7 @@ def test_invalid_names_raise(self):
     self.assertRaises(ValueError, Counter, '', 'help', subsystem='(')
     self.assertRaises(ValueError, Counter, 'c', '', labelnames=['^'])
     self.assertRaises(ValueError, Counter, 'c', '', labelnames=['__reserved'])
+    self.assertRaises(ValueError, Summary, 'c', '', labelnames=['quantile'])
 
 class TestGenerateText(unittest.TestCase):
   def setUp(self):