fix(metric): only print help/type once for summaries

README.md

@@ -83,7 +83,7 @@ with Chrome, curl, and Prometheus itself.
 
 ### Labels
 
-Labels are not yet implemented.
+Labels are stored and used to accumulate values. Missing labels are reported as `None`.
 
 ### Metric Types
 
@@ -99,7 +99,7 @@ Absolute values. Extends [counter](#counter) with `set(value)`.
 
 #### Summary
 
-Prints count and total of `observe(value)`.
+Individual values. Prints count and total of `observe(value)`.
 
 ### Registries
 
@@ -147,7 +147,7 @@ Transfer/sec:     32.60KB
 
 Some are fatal:
 
-```
+```none
 Connection from ('client', 8080)
 Accepting...
 Connection from ('client', 8080)
@@ -165,7 +165,7 @@ OSError: 4
 
 Others require the socket to be rebound:
 
-```
+```none
 Connection from ('client', 8080)
 Accepting...
 Error accepting request: 7

prometheus_express/metric.py

@@ -143,9 +143,7 @@ def render(self, namespace):
         lines = super(Summary, self).render(namespace)
         for l, v in self.values.items():
             ll = render_labels(self.labelKeys, l)
-            lines.extend(render_help(nn + '_count', self.desc, self.metricType))
             lines.append('{}_count{} {}'.format(nn, ll, v[0]))
-            lines.extend(render_help(nn + '_total', self.desc, self.metricType))
             lines.append('{}_total{} {}'.format(nn, ll, v[1]))
 
         return lines

tests/test_metric.py

@@ -67,7 +67,7 @@ def test(self):
     ], r)
 
 class CounterRenderTest(unittest.TestCase):
-  def test(self):
+  def test_simple(self):
     m = pm.Counter('bin', 'bin values', [
       'key_1', 'key_2',
     ])
@@ -86,3 +86,55 @@ def test(self):
       'foo_bin{key_1="None",key_2="None"} 0',
       'foo_bin{key_1="value-1",key_2="value-2"} 90',
     ], v)
+
+  '''
+  ensure repeated label sets are combined and values
+  are accumulated correctly
+  '''
+  def test_repeat_labels(self):
+    m = pm.Counter('bin', 'bin values', [
+      'key_1', 'key_2',
+    ])
+    m.labels('value-1', 'value-2')
+    m.inc(30)
+
+    m.labels('foo-1', 'foo-2')
+    m.inc(20)
+
+    m.labels('value-1', 'value-2')
+    m.inc(60)
+
+    r = m.render('foo')
+    v = r[2:]
+    v.sort()
+    self.assertEqual([
+      'foo_bin{key_1="None",key_2="None"} 0',
+      'foo_bin{key_1="foo-1",key_2="foo-2"} 20',
+      'foo_bin{key_1="value-1",key_2="value-2"} 90',
+    ], v)
+
+class SummaryRenderTest(unittest.TestCase):
+  def test(self):
+    m = pm.Summary('foo', 'foo values', ['group'])
+    m.labels('foo').observe(4)
+    m.labels('bar').observe(2)
+    m.labels('foo').observe(6)
+    m.labels('bar').observe(8)
+
+    r = m.render('bar')
+    self.assertEqual(len(r), 8, 'should have 2 lines of help and 6 values')
+    self.assertEqual(r[:2], [
+      '# HELP bar_foo foo values',
+      '# TYPE bar_foo summary',
+    ], 'should begin with the help and type lines')
+
+    v = r[2:]
+    v.sort()
+    self.assertEqual([
+      'bar_foo_count{group="None"} 0',
+      'bar_foo_count{group="bar"} 2',
+      'bar_foo_count{group="foo"} 2',
+      'bar_foo_total{group="None"} 0',
+      'bar_foo_total{group="bar"} 10',
+      'bar_foo_total{group="foo"} 10',
+    ], v)