Added metrics to MetricFamily exceptions to fix #362

prometheus_client/exposition.py

@@ -87,36 +87,41 @@ def sample_line(s):
 
  output = []
  for metric in registry.collect():
- mname = metric.name
- mtype = metric.type
- # Munging from OpenMetrics into Prometheus format.
- if mtype == 'counter':
- mname = mname + '_total'
- elif mtype == 'info':
- mname = mname + '_info'
- mtype = 'gauge'
- elif mtype == 'stateset':
- mtype = 'gauge'
- elif mtype == 'gaugehistogram':
- # A gauge histogram is really a gauge,
- # but this captures the strucutre better.
- mtype = 'histogram'
- elif mtype == 'unknown':
- mtype = 'untyped'
-
- output.append('# HELP {0} {1}\n'.format(
- mname, metric.documentation.replace('\\', r'\\').replace('\n', r'\n')))
- output.append('# TYPE {0} {1}\n'.format(mname, mtype))
-
- om_samples = {}
- for s in metric.samples:
- for suffix in ['_created', '_gsum', '_gcount']:
- if s.name == metric.name + suffix:
- # OpenMetrics specific sample, put in a gauge at the end.
- om_samples.setdefault(suffix, []).append(sample_line(s))
- break
- else:
- output.append(sample_line(s))
+ try:
+ mname = metric.name
+ mtype = metric.type
+ # Munging from OpenMetrics into Prometheus format.
+ if mtype == 'counter':
+ mname = mname + '_total'
+ elif mtype == 'info':
+ mname = mname + '_info'
+ mtype = 'gauge'
+ elif mtype == 'stateset':
+ mtype = 'gauge'
+ elif mtype == 'gaugehistogram':
+ # A gauge histogram is really a gauge,
+ # but this captures the strucutre better.
+ mtype = 'histogram'
+ elif mtype == 'unknown':
+ mtype = 'untyped'
+
+ output.append('# HELP {0} {1}\n'.format(
+ mname, metric.documentation.replace('\\', r'\\').replace('\n', r'\n')))
+ output.append('# TYPE {0} {1}\n'.format(mname, mtype))
+
+ om_samples = {}
+ for s in metric.samples:
+ for suffix in ['_created', '_gsum', '_gcount']:
+ if s.name == metric.name + suffix:
+ # OpenMetrics specific sample, put in a gauge at the end.
+ om_samples.setdefault(suffix, []).append(sample_line(s))
+ break
+ else:
+ output.append(sample_line(s))
+ except Exception as exception:
+ exception.args = (exception.args or ('',)) + (metric,)
+ raise
+
  for suffix, lines in sorted(om_samples.items()):
  output.append('# TYPE {0}{1} gauge\n'.format(metric.name, suffix))
  output.extend(lines)

prometheus_client/openmetrics/exposition.py

@@ -12,49 +12,54 @@ def generate_latest(registry):
  '''Returns the metrics from the registry in latest text format as a string.'''
  output = []
  for metric in registry.collect():
- mname = metric.name
- output.append('# HELP {0} {1}\n'.format(
- mname, metric.documentation.replace('\\', r'\\').replace('\n', r'\n').replace('"', r'\"')))
- output.append('# TYPE {0} {1}\n'.format(mname, metric.type))
- if metric.unit:
- output.append('# UNIT {0} {1}\n'.format(mname, metric.unit))
- for s in metric.samples:
- if s.labels:
- labelstr = '{{{0}}}'.format(','.join(
- ['{0}="{1}"'.format(
- k, v.replace('\\', r'\\').replace('\n', r'\n').replace('"', r'\"'))
- for k, v in sorted(s.labels.items())]))
- else:
- labelstr = ''
- if s.exemplar:
- if metric.type not in ('histogram', 'gaugehistogram') or not s.name.endswith('_bucket'):
- raise ValueError("Metric {0} has exemplars, but is not a histogram bucket".format(metric.name))
- labels = '{{{0}}}'.format(','.join(
- ['{0}="{1}"'.format(
- k, v.replace('\\', r'\\').replace('\n', r'\n').replace('"', r'\"'))
- for k, v in sorted(s.exemplar.labels.items())]))
- if s.exemplar.timestamp is not None:
- exemplarstr = ' # {0} {1} {2}'.format(
- labels,
- floatToGoString(s.exemplar.value),
- s.exemplar.timestamp,
- )
+ try:
+ mname = metric.name
+ output.append('# HELP {0} {1}\n'.format(
+ mname, metric.documentation.replace('\\', r'\\').replace('\n', r'\n').replace('"', r'\"')))
+ output.append('# TYPE {0} {1}\n'.format(mname, metric.type))
+ if metric.unit:
+ output.append('# UNIT {0} {1}\n'.format(mname, metric.unit))
+ for s in metric.samples:
+ if s.labels:
+ labelstr = '{{{0}}}'.format(','.join(
+ ['{0}="{1}"'.format(
+ k, v.replace('\\', r'\\').replace('\n', r'\n').replace('"', r'\"'))
+ for k, v in sorted(s.labels.items())]))
  else:
- exemplarstr = ' # {0} {1}'.format(
- labels,
- floatToGoString(s.exemplar.value),
- )
- else:
- exemplarstr = ''
- timestamp = ''
- if s.timestamp is not None:
- timestamp = ' {0}'.format(s.timestamp)
- output.append('{0}{1} {2}{3}{4}\n'.format(
- s.name,
- labelstr,
- floatToGoString(s.value),
- timestamp,
- exemplarstr,
- ))
+ labelstr = ''
+ if s.exemplar:
+ if metric.type not in ('histogram', 'gaugehistogram') or not s.name.endswith('_bucket'):
+ raise ValueError("Metric {0} has exemplars, but is not a histogram bucket".format(metric.name))
+ labels = '{{{0}}}'.format(','.join(
+ ['{0}="{1}"'.format(
+ k, v.replace('\\', r'\\').replace('\n', r'\n').replace('"', r'\"'))
+ for k, v in sorted(s.exemplar.labels.items())]))
+ if s.exemplar.timestamp is not None:
+ exemplarstr = ' # {0} {1} {2}'.format(
+ labels,
+ floatToGoString(s.exemplar.value),
+ s.exemplar.timestamp,
+ )
+ else:
+ exemplarstr = ' # {0} {1}'.format(
+ labels,
+ floatToGoString(s.exemplar.value),
+ )
+ else:
+ exemplarstr = ''
+ timestamp = ''
+ if s.timestamp is not None:
+ timestamp = ' {0}'.format(s.timestamp)
+ output.append('{0}{1} {2}{3}{4}\n'.format(
+ s.name,
+ labelstr,
+ floatToGoString(s.value),
+ timestamp,
+ exemplarstr,
+ ))
+ except Exception as exception:
+ exception.args = (exception.args or ('',)) + (metric,)
+ raise
+
  output.append('# EOF\n')
  return ''.join(output).encode('utf-8')

tests/test_exposition.py

@@ -3,6 +3,7 @@
 import sys
 import threading
 import time
+import pytest
 
 from prometheus_client import (
  CollectorRegistry, CONTENT_TYPE_LATEST, Counter, delete_from_gateway, Enum,
@@ -11,8 +12,9 @@
 )
 from prometheus_client.core import GaugeHistogramMetricFamily, Timestamp
 from prometheus_client.exposition import (
- basic_auth_handler, default_handler, MetricsHandler,
+ basic_auth_handler, default_handler, MetricsHandler, generate_latest,
 )
+from prometheus_client import core
 
 if sys.version_info < (2, 7):
  # We need the skip decorators from unittest2 on Python 2.6.
@@ -303,5 +305,84 @@ def test_metrics_handler_subclassing(self):
  self.assertTrue(issubclass(handler, (MetricsHandler, subclass)))
 
 
+@pytest.fixture
+def registry():
+ return core.CollectorRegistry()
+
+
+class Collector:
+ def __init__(self, metric_family, *values):
+ self.metric_family = metric_family
+ self.values = values
+
+ def collect(self):
+ self.metric_family.add_metric([], *self.values)
+ return [self.metric_family]
+
+
+def _expect_metric_exception(registry, expected_error):
+ try:
+ generate_latest(registry)
+ except expected_error as exception:
+ assert isinstance(exception.args[-1], core.Metric)
+ # Got a valid error as expected, return quietly
+ return
+
+ raise RuntimeError('Expected exception not raised')
+
+
+@pytest.mark.parametrize('MetricFamily', [
+ core.CounterMetricFamily,
+ core.GaugeMetricFamily,
+])
+@pytest.mark.parametrize('value,error', [
+ (None, TypeError),
+ ('', ValueError),
+ ('x', ValueError),
+ ([], TypeError),
+ ({}, TypeError),
+])
+def test_basic_metric_families(registry, MetricFamily, value, error):
+ metric_family = MetricFamily(MetricFamily.__name__, 'help')
+ registry.register(Collector(metric_family, value))
+ _expect_metric_exception(registry, error)
+
+
+@pytest.mark.parametrize('count_value,sum_value,error', [
+ (None, 0, TypeError),
+ (0, None, TypeError),
+ ('', 0, ValueError),
+ (0, '', ValueError),
+ ([], 0, TypeError),
+ (0, [], TypeError),
+ ({}, 0, TypeError),
+ (0, {}, TypeError),
+])
+def test_summary_metric_family(registry, count_value, sum_value, error):
+ metric_family = core.SummaryMetricFamily('summary', 'help')
+ registry.register(Collector(metric_family, count_value, sum_value))
+ _expect_metric_exception(registry, error)
+
+
+@pytest.mark.parametrize('MetricFamily', [
+ core.HistogramMetricFamily,
+ core.GaugeHistogramMetricFamily,
+])
+@pytest.mark.parametrize('buckets,sum_value,error', [
+ ([('spam', 0), ('eggs', 0)], None, TypeError),
+ ([('spam', 0), ('eggs', None)], 0, TypeError),
+ ([('spam', 0), (None, 0)], 0, AttributeError),
+ ([('spam', None), ('eggs', 0)], 0, TypeError),
+ ([(None, 0), ('eggs', 0)], 0, AttributeError),
+ ([('spam', 0), ('eggs', 0)], '', ValueError),
+ ([('spam', 0), ('eggs', '')], 0, ValueError),
+ ([('spam', ''), ('eggs', 0)], 0, ValueError),
+])
+def test_histogram_metric_families(MetricFamily, registry, buckets, sum_value, error):
+ metric_family = MetricFamily(MetricFamily.__name__, 'help')
+ registry.register(Collector(metric_family, buckets, sum_value))
+ _expect_metric_exception(registry, error)
+
+
 if __name__ == '__main__':
  unittest.main()