Merge pull request #306 from prometheus/openmetrics

Add gsum/gcount to GaugeHistogram.

Author: brian-brazil

prometheus_client/core.py

@@ -49,6 +49,8 @@ class Timestamp(object):
     def __init__(self, sec, nsec):
         if nsec < 0 or nsec >= 1e9:
             raise ValueError("Invalid value for nanoseconds in Timestamp: {}".format(nsec))
+        if sec < 0:
+            nsec = -nsec
         self.sec = int(sec)
         self.nsec = int(nsec)
 
@@ -64,6 +66,12 @@ def __float__(self):
     def __eq__(self, other):
         return type(self) == type(other) and self.sec == other.sec and self.nsec == other.nsec
 
+    def __ne__(self, other):
+        return not self == other
+
+    def __gt__(self, other):
+        return self.sec > other.sec or self.nsec > other.nsec
+
 
 Exemplar = namedtuple('Exemplar', ['labels', 'value', 'timestamp'])
 Exemplar.__new__.__defaults__ = (None, )
@@ -122,6 +130,7 @@ def _get_names(self, collector):
             'counter': ['_total', '_created'],
             'summary': ['', '_sum', '_count', '_created'],
             'histogram': ['_bucket', '_sum', '_count', '_created'],
+            'gaugehistogram': ['_bucket', '_gsum', '_gcount'],
             'info': ['_info'],
         }
         for metric in desc_func():
@@ -391,29 +400,33 @@ class GaugeHistogramMetricFamily(Metric):
 
     For use by custom collectors.
     '''
-    def __init__(self, name, documentation, buckets=None, labels=None, unit=''):
+    def __init__(self, name, documentation, buckets=None, gsum_value=None, labels=None, unit=''):
         Metric.__init__(self, name, documentation, 'gaugehistogram', unit)
         if labels is not None and buckets is not None:
             raise ValueError('Can only specify at most one of buckets and labels.')
         if labels is None:
             labels = []
         self._labelnames = tuple(labels)
         if buckets is not None:
-            self.add_metric([], buckets)
+            self.add_metric([], buckets, gsum_value)
 
-    def add_metric(self, labels, buckets, timestamp=None):
+    def add_metric(self, labels, buckets, gsum_value, timestamp=None):
         '''Add a metric to the metric family.
 
         Args:
           labels: A list of label values
           buckets: A list of pairs of bucket names and values.
               The buckets must be sorted, and +Inf present.
+          gsum_value: The sum value of the metric.
         '''
         for bucket, value in buckets:
             self.samples.append(Sample(
                 self.name + '_bucket',
                 dict(list(zip(self._labelnames, labels)) + [('le', bucket)]),
                 value, timestamp))
+        # +Inf is last and provides the count value.
+        self.samples.append(Sample(self.name + '_gcount', dict(zip(self._labelnames, labels)), buckets[-1][1], timestamp))
+        self.samples.append(Sample(self.name + '_gsum', dict(zip(self._labelnames, labels)), gsum_value, timestamp))
 
 
 class InfoMetricFamily(Metric):
@@ -465,7 +478,7 @@ def add_metric(self, labels, value, timestamp=None):
           value: A dict of string state names to booleans
         '''
         labels = tuple(labels)
-        for state, enabled in value.items():
+        for state, enabled in sorted(value.items()):
             v = (1 if enabled else 0)
             self.samples.append(Sample(self.name,
                 dict(zip(self._labelnames + (self.name,), labels + (state,))), v, timestamp))

prometheus_client/exposition.py

@@ -67,6 +67,22 @@ def start_wsgi_server(port, addr='', registry=core.REGISTRY):
 
 def generate_latest(registry=core.REGISTRY):
     '''Returns the metrics from the registry in latest text format as a string.'''
+
+    def sample_line(s):
+        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 = ''
+        timestamp = ''
+        if s.timestamp is not None:
+            # Convert to milliseconds.
+            timestamp = ' {0:d}'.format(int(float(s.timestamp) * 1000))
+        return '{0}{1} {2}{3}\n'.format(
+            s.name, labelstr, core._floatToGoString(s.value), timestamp)
+
     output = []
     for metric in registry.collect():
         mname = metric.name
@@ -86,32 +102,29 @@ def generate_latest(registry=core.REGISTRY):
         elif mtype == 'unknown':
             mtype = 'untyped'
 
-        output.append('# HELP {0} {1}'.format(
+        output.append('# HELP {0} {1}\n'.format(
             mname, metric.documentation.replace('\\', r'\\').replace('\n', r'\n')))
-        output.append('\n# TYPE {0} {1}\n'.format(mname, mtype))
+        output.append('# TYPE {0} {1}\n'.format(mname, mtype))
+
+        om_samples = {}
         for s in metric.samples:
-            if s.name == metric.name + '_created':
-                continue  # Ignore OpenMetrics specific sample. TODO: Make these into a gauge.
-            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())]))
+            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:
-                labelstr = ''
-            timestamp = ''
-            if s.timestamp is not None:
-                # Convert to milliseconds.
-                timestamp = ' {0:d}'.format(int(float(s.timestamp) * 1000))
-            output.append('{0}{1} {2}{3}\n'.format(
-                s.name, labelstr, core._floatToGoString(s.value), timestamp))
+                output.append(sample_line(s))
+        for suffix, lines in sorted(om_samples.items()):
+            output.append('# TYPE {0}{1} gauge\n'.format(metric.name, suffix))
+            output.extend(lines)
     return ''.join(output).encode('utf-8')
 
 
 def choose_encoder(accept_header):
     accept_header = accept_header or ''
     for accepted in accept_header.split(','):
-        if accepted == 'text/openmetrics; version=0.0.1':
+        if accepted == 'application/openmetrics-text; version=0.0.1':
             return (openmetrics.exposition.generate_latest, 
                     openmetrics.exposition.CONTENT_TYPE_LATEST)
     return (generate_latest, CONTENT_TYPE_LATEST)

prometheus_client/openmetrics/exposition.py

@@ -4,7 +4,7 @@
 
 from .. import core
 
-CONTENT_TYPE_LATEST = str('text/openmetrics; version=0.0.1; charset=utf-8')
+CONTENT_TYPE_LATEST = str('application/openmetrics-text; version=0.0.1; charset=utf-8')
 '''Content type of the latest OpenMetrics text format'''
 
 def generate_latest(registry):
@@ -26,7 +26,7 @@ def generate_latest(registry):
             else:
                 labelstr = ''
             if s.exemplar:
-                if metric.type != 'histogram' or not s.name.endswith('_bucket'):
+                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(
@@ -42,7 +42,6 @@ def generate_latest(registry):
                 exemplarstr = ''
             timestamp = ''
             if s.timestamp is not None:
-                # Convert to milliseconds.
                 timestamp = ' {0}'.format(s.timestamp)
             output.append('{0}{1} {2}{3}{4}\n'.format(s.name, labelstr,
                 core._floatToGoString(s.value), timestamp, exemplarstr))