Change exemplar limit to 128 chars.

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>

Author: brian-brazil

prometheus_client/openmetrics/parser.py

@@ -359,7 +359,7 @@ def _parse_remaining_text(text):
     exemplar = None
     if exemplar_labels is not None:
         exemplar_length = sum([len(k) + len(v) for k, v in exemplar_labels.items()])
-        if exemplar_length > 64:
+        if exemplar_length > 128:
             raise ValueError("Exmplar labels are too long: " + text)
         exemplar = Exemplar(
             exemplar_labels,

tests/openmetrics/test_parser.py

@@ -152,14 +152,14 @@ def test_histogram_exemplars(self):
 # HELP a help
 a_bucket{le="1.0"} 0 # {a="b"} 0.5
 a_bucket{le="2.0"} 2 # {a="c"} 0.5
-a_bucket{le="+Inf"} 3 # {a="1234567890123456789012345678901234567890123456789012345678"} 4 123
+a_bucket{le="+Inf"} 3 # {a="2345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678"} 4 123
 # EOF
 """)
         hfm = HistogramMetricFamily("a", "help")
         hfm.add_sample("a_bucket", {"le": "1.0"}, 0.0, None, Exemplar({"a": "b"}, 0.5))
         hfm.add_sample("a_bucket", {"le": "2.0"}, 2.0, None, Exemplar({"a": "c"}, 0.5)),
         hfm.add_sample("a_bucket", {"le": "+Inf"}, 3.0, None,
-                       Exemplar({"a": "1234567890123456789012345678901234567890123456789012345678"}, 4,
+                       Exemplar({"a": "2345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678"}, 4,
                                 Timestamp(123, 0)))
         self.assertEqual([hfm], list(families))
 
@@ -693,7 +693,7 @@ def test_invalid_input(self):
             ('# TYPE a histogram\na_bucket{le="+Inf"} 1 # {} 1 \n# EOF\n'),
             ('# TYPE a histogram\na_bucket{le="+Inf"} 1 # {} 1 1 \n# EOF\n'),
             ('# TYPE a histogram\na_bucket{le="+Inf"} 1 # '
-             '{a="2345678901234567890123456789012345678901234567890123456789012345"} 1 1\n# EOF\n'),
+             '{a="23456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789"} 1 1\n# EOF\n'),
             ('# TYPE a histogram\na_bucket{le="+Inf"} 1 # {} 0x1p-3\n# EOF\n'),
             ('# TYPE a histogram\na_bucket{le="+Inf"} 1 # {} 1 0x1p-3\n# EOF\n'),
             # Exemplars on unallowed samples.