[exporter-otlp-proto-common] Include metric info in encoding exception

CHANGELOG.md

@@ -34,6 +34,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Remove `_start_time_unix_nano` attribute from `_ViewInstrumentMatch` in favor
   of using `time_ns()` at the moment when the aggregation object is created
   ([#4137](https://github.com/open-telemetry/opentelemetry-python/pull/4137))
+- Include metric info in encoding exceptions
+  ([#4137](https://github.com/open-telemetry/opentelemetry-python/pull/4154))
 
 ## Version 1.26.0/0.47b0 (2024-07-25)
 

exporter/opentelemetry-exporter-otlp-proto-common/src/opentelemetry/exporter/otlp/proto/common/_internal/metrics_encoder/__init__.py

@@ -173,152 +173,26 @@ def _get_aggregation(
         return instrument_class_aggregation
 
 
-def encode_metrics(data: MetricsData) -> ExportMetricsServiceRequest:
-    resource_metrics_dict = {}
-
-    for resource_metrics in data.resource_metrics:
-
-        resource = resource_metrics.resource
+class EncodingException(Exception):
+    """
+    Raised by encode_metrics() when an exception is caught during encoding. Contains the problematic metric so
+    the misbehaving metric name and details can be logged during exception handling.
+    """
 
-        # It is safe to assume that each entry in data.resource_metrics is
-        # associated with an unique resource.
-        scope_metrics_dict = {}
+    def __init__(self, original_exception, metric):
+        super().__init__()
+        self.original_exception = original_exception
+        self.metric = metric
 
-        resource_metrics_dict[resource] = scope_metrics_dict
-
-        for scope_metrics in resource_metrics.scope_metrics:
-
-            instrumentation_scope = scope_metrics.scope
-
-            # The SDK groups metrics in instrumentation scopes already so
-            # there is no need to check for existing instrumentation scopes
-            # here.
-            pb2_scope_metrics = pb2.ScopeMetrics(
-                scope=InstrumentationScope(
-                    name=instrumentation_scope.name,
-                    version=instrumentation_scope.version,
-                )
-            )
+    def __str__(self):
+        return f"{self.metric}\n{self.original_exception}"
 
-            scope_metrics_dict[instrumentation_scope] = pb2_scope_metrics
 
-            for metric in scope_metrics.metrics:
-                pb2_metric = pb2.Metric(
-                    name=metric.name,
-                    description=metric.description,
-                    unit=metric.unit,
-                )
+def encode_metrics(data: MetricsData) -> ExportMetricsServiceRequest:
+    resource_metrics_dict = {}
 
-                if isinstance(metric.data, Gauge):
-                    for data_point in metric.data.data_points:
-                        pt = pb2.NumberDataPoint(
-                            attributes=_encode_attributes(
-                                data_point.attributes
-                            ),
-                            time_unix_nano=data_point.time_unix_nano,
-                        )
-                        if isinstance(data_point.value, int):
-                            pt.as_int = data_point.value
-                        else:
-                            pt.as_double = data_point.value
-                        pb2_metric.gauge.data_points.append(pt)
-
-                elif isinstance(metric.data, HistogramType):
-                    for data_point in metric.data.data_points:
-                        pt = pb2.HistogramDataPoint(
-                            attributes=_encode_attributes(
-                                data_point.attributes
-                            ),
-                            time_unix_nano=data_point.time_unix_nano,
-                            start_time_unix_nano=(
-                                data_point.start_time_unix_nano
-                            ),
-                            count=data_point.count,
-                            sum=data_point.sum,
-                            bucket_counts=data_point.bucket_counts,
-                            explicit_bounds=data_point.explicit_bounds,
-                            max=data_point.max,
-                            min=data_point.min,
-                        )
-                        pb2_metric.histogram.aggregation_temporality = (
-                            metric.data.aggregation_temporality
-                        )
-                        pb2_metric.histogram.data_points.append(pt)
-
-                elif isinstance(metric.data, Sum):
-                    for data_point in metric.data.data_points:
-                        pt = pb2.NumberDataPoint(
-                            attributes=_encode_attributes(
-                                data_point.attributes
-                            ),
-                            start_time_unix_nano=(
-                                data_point.start_time_unix_nano
-                            ),
-                            time_unix_nano=data_point.time_unix_nano,
-                        )
-                        if isinstance(data_point.value, int):
-                            pt.as_int = data_point.value
-                        else:
-                            pt.as_double = data_point.value
-                        # note that because sum is a message type, the
-                        # fields must be set individually rather than
-                        # instantiating a pb2.Sum and setting it once
-                        pb2_metric.sum.aggregation_temporality = (
-                            metric.data.aggregation_temporality
-                        )
-                        pb2_metric.sum.is_monotonic = metric.data.is_monotonic
-                        pb2_metric.sum.data_points.append(pt)
-
-                elif isinstance(metric.data, ExponentialHistogramType):
-                    for data_point in metric.data.data_points:
-
-                        if data_point.positive.bucket_counts:
-                            positive = pb2.ExponentialHistogramDataPoint.Buckets(
-                                offset=data_point.positive.offset,
-                                bucket_counts=data_point.positive.bucket_counts,
-                            )
-                        else:
-                            positive = None
-
-                        if data_point.negative.bucket_counts:
-                            negative = pb2.ExponentialHistogramDataPoint.Buckets(
-                                offset=data_point.negative.offset,
-                                bucket_counts=data_point.negative.bucket_counts,
-                            )
-                        else:
-                            negative = None
-
-                        pt = pb2.ExponentialHistogramDataPoint(
-                            attributes=_encode_attributes(
-                                data_point.attributes
-                            ),
-                            time_unix_nano=data_point.time_unix_nano,
-                            start_time_unix_nano=(
-                                data_point.start_time_unix_nano
-                            ),
-                            count=data_point.count,
-                            sum=data_point.sum,
-                            scale=data_point.scale,
-                            zero_count=data_point.zero_count,
-                            positive=positive,
-                            negative=negative,
-                            flags=data_point.flags,
-                            max=data_point.max,
-                            min=data_point.min,
-                        )
-                        pb2_metric.exponential_histogram.aggregation_temporality = (
-                            metric.data.aggregation_temporality
-                        )
-                        pb2_metric.exponential_histogram.data_points.append(pt)
-
-                else:
-                    _logger.warning(
-                        "unsupported data type %s",
-                        metric.data.__class__.__name__,
-                    )
-                    continue
-
-                pb2_scope_metrics.metrics.append(pb2_metric)
+    for resource_metrics in data.resource_metrics:
+        _encode_resource_metrics(resource_metrics, resource_metrics_dict)
 
     resource_data = []
     for (
@@ -334,5 +208,137 @@ def encode_metrics(data: MetricsData) -> ExportMetricsServiceRequest:
                 schema_url=sdk_resource.schema_url,
             )
         )
-    resource_metrics = resource_data
-    return ExportMetricsServiceRequest(resource_metrics=resource_metrics)
+    return ExportMetricsServiceRequest(resource_metrics=resource_data)
+
+
+def _encode_resource_metrics(resource_metrics, resource_metrics_dict):
+    resource = resource_metrics.resource
+    # It is safe to assume that each entry in data.resource_metrics is
+    # associated with an unique resource.
+    scope_metrics_dict = {}
+    resource_metrics_dict[resource] = scope_metrics_dict
+    for scope_metrics in resource_metrics.scope_metrics:
+        instrumentation_scope = scope_metrics.scope
+
+        # The SDK groups metrics in instrumentation scopes already so
+        # there is no need to check for existing instrumentation scopes
+        # here.
+        pb2_scope_metrics = pb2.ScopeMetrics(
+            scope=InstrumentationScope(
+                name=instrumentation_scope.name,
+                version=instrumentation_scope.version,
+            )
+        )
+
+        scope_metrics_dict[instrumentation_scope] = pb2_scope_metrics
+
+        for metric in scope_metrics.metrics:
+            pb2_metric = pb2.Metric(
+                name=metric.name,
+                description=metric.description,
+                unit=metric.unit,
+            )
+
+            try:
+                _encode_metric(metric, pb2_metric)
+            except Exception as ex:
+                # `from None` so we don't get "During handling of the above exception, another exception occurred:"
+                raise EncodingException(ex, metric) from None
+
+            pb2_scope_metrics.metrics.append(pb2_metric)
+
+
+def _encode_metric(metric, pb2_metric):
+    if isinstance(metric.data, Gauge):
+        for data_point in metric.data.data_points:
+            pt = pb2.NumberDataPoint(
+                attributes=_encode_attributes(data_point.attributes),
+                time_unix_nano=data_point.time_unix_nano,
+            )
+            if isinstance(data_point.value, int):
+                pt.as_int = data_point.value
+            else:
+                pt.as_double = data_point.value
+            pb2_metric.gauge.data_points.append(pt)
+
+    elif isinstance(metric.data, HistogramType):
+        for data_point in metric.data.data_points:
+            pt = pb2.HistogramDataPoint(
+                attributes=_encode_attributes(data_point.attributes),
+                time_unix_nano=data_point.time_unix_nano,
+                start_time_unix_nano=data_point.start_time_unix_nano,
+                count=data_point.count,
+                sum=data_point.sum,
+                bucket_counts=data_point.bucket_counts,
+                explicit_bounds=data_point.explicit_bounds,
+                max=data_point.max,
+                min=data_point.min,
+            )
+            pb2_metric.histogram.aggregation_temporality = (
+                metric.data.aggregation_temporality
+            )
+            pb2_metric.histogram.data_points.append(pt)
+
+    elif isinstance(metric.data, Sum):
+        for data_point in metric.data.data_points:
+            pt = pb2.NumberDataPoint(
+                attributes=_encode_attributes(data_point.attributes),
+                start_time_unix_nano=data_point.start_time_unix_nano,
+                time_unix_nano=data_point.time_unix_nano,
+            )
+            if isinstance(data_point.value, int):
+                pt.as_int = data_point.value
+            else:
+                pt.as_double = data_point.value
+            # note that because sum is a message type, the
+            # fields must be set individually rather than
+            # instantiating a pb2.Sum and setting it once
+            pb2_metric.sum.aggregation_temporality = (
+                metric.data.aggregation_temporality
+            )
+            pb2_metric.sum.is_monotonic = metric.data.is_monotonic
+            pb2_metric.sum.data_points.append(pt)
+
+    elif isinstance(metric.data, ExponentialHistogramType):
+        for data_point in metric.data.data_points:
+
+            if data_point.positive.bucket_counts:
+                positive = pb2.ExponentialHistogramDataPoint.Buckets(
+                    offset=data_point.positive.offset,
+                    bucket_counts=data_point.positive.bucket_counts,
+                )
+            else:
+                positive = None
+
+            if data_point.negative.bucket_counts:
+                negative = pb2.ExponentialHistogramDataPoint.Buckets(
+                    offset=data_point.negative.offset,
+                    bucket_counts=data_point.negative.bucket_counts,
+                )
+            else:
+                negative = None
+
+            pt = pb2.ExponentialHistogramDataPoint(
+                attributes=_encode_attributes(data_point.attributes),
+                time_unix_nano=data_point.time_unix_nano,
+                start_time_unix_nano=data_point.start_time_unix_nano,
+                count=data_point.count,
+                sum=data_point.sum,
+                scale=data_point.scale,
+                zero_count=data_point.zero_count,
+                positive=positive,
+                negative=negative,
+                flags=data_point.flags,
+                max=data_point.max,
+                min=data_point.min,
+            )
+            pb2_metric.exponential_histogram.aggregation_temporality = (
+                metric.data.aggregation_temporality
+            )
+            pb2_metric.exponential_histogram.data_points.append(pt)
+
+    else:
+        _logger.warning(
+            "unsupported data type %s",
+            metric.data.__class__.__name__,
+        )

exporter/opentelemetry-exporter-otlp-proto-common/tests/test_metrics_encoder.py

@@ -15,6 +15,9 @@
 # pylint: disable=protected-access
 import unittest
 
+from opentelemetry.exporter.otlp.proto.common._internal.metrics_encoder import (
+    EncodingException,
+)
 from opentelemetry.exporter.otlp.proto.common.metrics_encoder import (
     encode_metrics,
 )
@@ -814,3 +817,35 @@ def test_encode_exponential_histogram(self):
         # pylint: disable=protected-access
         actual = encode_metrics(metrics_data)
         self.assertEqual(expected, actual)
+
+    def test_encoding_exception_reraise(self):
+        # this number is too big to fit in a signed 64-bit proto field and causes a ValueError
+        big_number = 2**63
+        metrics_data = MetricsData(
+            resource_metrics=[
+                ResourceMetrics(
+                    resource=Resource(
+                        attributes={},
+                        schema_url="resource_schema_url",
+                    ),
+                    scope_metrics=[
+                        ScopeMetrics(
+                            scope=SDKInstrumentationScope(
+                                name="first_name",
+                                version="first_version",
+                                schema_url="insrumentation_scope_schema_url",
+                            ),
+                            metrics=[_generate_sum("sum_double", big_number)],
+                            schema_url="instrumentation_scope_schema_url",
+                        )
+                    ],
+                    schema_url="resource_schema_url",
+                )
+            ]
+        )
+        with self.assertRaises(EncodingException) as context:
+            encode_metrics(metrics_data)
+
+        # assert that the EncodingException wraps the metric and original exception
+        assert isinstance(context.exception.metric, Metric)
+        assert isinstance(context.exception.original_exception, ValueError)

opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/export/__init__.py

@@ -541,8 +541,8 @@ def _receive_metrics(
                 self._exporter.export(
                     metrics_data, timeout_millis=timeout_millis
                 )
-        except Exception as e:
-            _logger.exception("Exception while exporting metrics %s", str(e))
+        except Exception:
+            _logger.exception("Exception while exporting metrics")
         detach(token)
 
     def shutdown(self, timeout_millis: float = 30_000, **kwargs) -> None: