Add missing to_json methods (open-telemetry#2722)

* Add missing to_json methods

Fixes open-telemetry#2716

* Added resource to_json method

* Rename to metrics data

* Add to_json to Instrumentation Scope as well

Fixes open-telemetry#2716

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased](https://github.com/open-telemetry/opentelemetry-python/compare/v1.12.0rc1-0.31b0...HEAD)
 
+- Add missing `to_json` methods
+  ([#2722](https://github.com/open-telemetry/opentelemetry-python/pull/2722)
 - Fix type hints for textmap `Getter` and `Setter`
   ([#2657](https://github.com/open-telemetry/opentelemetry-python/pull/2657))
 - Fix LogEmitterProvider.force_flush hanging randomly

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

@@ -105,8 +105,8 @@ def __init__(
         self,
         out: IO = stdout,
         formatter: Callable[
-            ["opentelemetry.sdk.metrics.export.Metric"], str
-        ] = lambda metric: metric.to_json()
+            ["opentelemetry.sdk.metrics.export.MetricsData"], str
+        ] = lambda metrics_data: metrics_data.to_json()
         + linesep,
     ):
         self.out = out

opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/point.py

@@ -15,8 +15,8 @@
 # pylint: disable=unused-import
 
 from dataclasses import asdict, dataclass
-from json import dumps
-from typing import Sequence, Union
+from json import dumps, loads
+from typing import Optional, Sequence, Union
 
 # This kind of import is needed to avoid Sphinx errors.
 import opentelemetry.sdk.metrics._internal
@@ -36,6 +36,29 @@ class NumberDataPoint:
     time_unix_nano: int
     value: Union[int, float]
 
+    def to_json(self, indent=4) -> str:
+        return dumps(asdict(self), indent=indent)
+
+
+@dataclass(frozen=True)
+class HistogramDataPoint:
+    """Single data point in a timeseries that describes the time-varying scalar
+    value of a metric.
+    """
+
+    attributes: Attributes
+    start_time_unix_nano: int
+    time_unix_nano: int
+    count: int
+    sum: Union[int, float]
+    bucket_counts: Sequence[int]
+    explicit_bounds: Sequence[float]
+    min: float
+    max: float
+
+    def to_json(self, indent=4) -> str:
+        return dumps(asdict(self), indent=indent)
+
 
 @dataclass(frozen=True)
 class Sum:
@@ -48,15 +71,17 @@ class Sum:
     )
     is_monotonic: bool
 
-    def to_json(self) -> str:
+    def to_json(self, indent=4) -> str:
         return dumps(
             {
-                "data_points": dumps(
-                    [asdict(data_point) for data_point in self.data_points]
-                ),
+                "data_points": [
+                    loads(data_point.to_json(indent=indent))
+                    for data_point in self.data_points
+                ],
                 "aggregation_temporality": self.aggregation_temporality,
                 "is_monotonic": self.is_monotonic,
-            }
+            },
+            indent=indent,
         )
 
 
@@ -68,33 +93,18 @@ class Gauge:
 
     data_points: Sequence[NumberDataPoint]
 
-    def to_json(self) -> str:
+    def to_json(self, indent=4) -> str:
         return dumps(
             {
-                "data_points": dumps(
-                    [asdict(data_point) for data_point in self.data_points]
-                )
-            }
+                "data_points": [
+                    loads(data_point.to_json(indent=indent))
+                    for data_point in self.data_points
+                ],
+            },
+            indent=indent,
         )
 
 
-@dataclass(frozen=True)
-class HistogramDataPoint:
-    """Single data point in a timeseries that describes the time-varying scalar
-    value of a metric.
-    """
-
-    attributes: Attributes
-    start_time_unix_nano: int
-    time_unix_nano: int
-    count: int
-    sum: Union[int, float]
-    bucket_counts: Sequence[int]
-    explicit_bounds: Sequence[float]
-    min: float
-    max: float
-
-
 @dataclass(frozen=True)
 class Histogram:
     """Represents the type of a metric that is calculated by aggregating as a
@@ -105,14 +115,16 @@ class Histogram:
         "opentelemetry.sdk.metrics.export.AggregationTemporality"
     )
 
-    def to_json(self) -> str:
+    def to_json(self, indent=4) -> str:
         return dumps(
             {
-                "data_points": dumps(
-                    [asdict(data_point) for data_point in self.data_points]
-                ),
+                "data_points": [
+                    loads(data_point.to_json(indent=indent))
+                    for data_point in self.data_points
+                ],
                 "aggregation_temporality": self.aggregation_temporality,
-            }
+            },
+            indent=indent,
         )
 
 
@@ -126,18 +138,19 @@ class Metric:
     exported."""
 
     name: str
-    description: str
-    unit: str
+    description: Optional[str]
+    unit: Optional[str]
     data: DataT
 
-    def to_json(self) -> str:
+    def to_json(self, indent=4) -> str:
         return dumps(
             {
                 "name": self.name,
-                "description": self.description if self.description else "",
-                "unit": self.unit if self.unit else "",
-                "data": self.data.to_json(),
-            }
+                "description": self.description or "",
+                "unit": self.unit or "",
+                "data": loads(self.data.to_json(indent=indent)),
+            },
+            indent=indent,
         )
 
 
@@ -149,6 +162,19 @@ class ScopeMetrics:
     metrics: Sequence[Metric]
     schema_url: str
 
+    def to_json(self, indent=4) -> str:
+        return dumps(
+            {
+                "scope": loads(self.scope.to_json(indent=indent)),
+                "metrics": [
+                    loads(metric.to_json(indent=indent))
+                    for metric in self.metrics
+                ],
+                "schema_url": self.schema_url,
+            },
+            indent=indent,
+        )
+
 
 @dataclass(frozen=True)
 class ResourceMetrics:
@@ -158,9 +184,32 @@ class ResourceMetrics:
     scope_metrics: Sequence[ScopeMetrics]
     schema_url: str
 
+    def to_json(self, indent=4) -> str:
+        return dumps(
+            {
+                "resource": loads(self.resource.to_json(indent=indent)),
+                "scope_metrics": [
+                    loads(scope_metrics.to_json(indent=indent))
+                    for scope_metrics in self.scope_metrics
+                ],
+                "schema_url": self.schema_url,
+            },
+            indent=indent,
+        )
+
 
 @dataclass(frozen=True)
 class MetricsData:
     """An array of ResourceMetrics"""
 
     resource_metrics: Sequence[ResourceMetrics]
+
+    def to_json(self, indent=4) -> str:
+        return dumps(
+            {
+                "resource_metrics": [
+                    loads(resource_metrics.to_json(indent=indent))
+                    for resource_metrics in self.resource_metrics
+                ]
+            }
+        )

opentelemetry-sdk/src/opentelemetry/sdk/resources/__init__.py

@@ -242,6 +242,15 @@ def __hash__(self):
             f"{dumps(self._attributes.copy(), sort_keys=True)}|{self._schema_url}"
         )
 
+    def to_json(self, indent=4) -> str:
+        return dumps(
+            {
+                "attributes": dict(self._attributes),
+                "schema_url": self._schema_url,
+            },
+            indent=indent,
+        )
+
 
 _EMPTY_RESOURCE = Resource({})
 _DEFAULT_RESOURCE = Resource(

opentelemetry-sdk/src/opentelemetry/sdk/util/instrumentation.py

@@ -11,7 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-import typing
+from json import dumps
+from typing import Optional
 
 from deprecated import deprecated
 
@@ -29,8 +30,8 @@ class InstrumentationInfo:
     def __init__(
         self,
         name: str,
-        version: typing.Optional[str] = None,
-        schema_url: typing.Optional[str] = None,
+        version: Optional[str] = None,
+        schema_url: Optional[str] = None,
     ):
         self._name = name
         self._version = version
@@ -59,11 +60,11 @@ def __lt__(self, value):
         )
 
     @property
-    def schema_url(self) -> typing.Optional[str]:
+    def schema_url(self) -> Optional[str]:
         return self._schema_url
 
     @property
-    def version(self) -> typing.Optional[str]:
+    def version(self) -> Optional[str]:
         return self._version
 
     @property
@@ -84,8 +85,8 @@ class InstrumentationScope:
     def __init__(
         self,
         name: str,
-        version: typing.Optional[str] = None,
-        schema_url: typing.Optional[str] = None,
+        version: Optional[str] = None,
+        schema_url: Optional[str] = None,
     ) -> None:
         self._name = name
         self._version = version
@@ -116,13 +117,23 @@ def __lt__(self, value: object) -> bool:
         )
 
     @property
-    def schema_url(self) -> typing.Optional[str]:
+    def schema_url(self) -> Optional[str]:
         return self._schema_url
 
     @property
-    def version(self) -> typing.Optional[str]:
+    def version(self) -> Optional[str]:
         return self._version
 
     @property
     def name(self) -> str:
         return self._name
+
+    def to_json(self, indent=4) -> str:
+        return dumps(
+            {
+                "name": self._name,
+                "version": self._version,
+                "schema_url": self._schema_url,
+            },
+            indent=indent,
+        )

opentelemetry-sdk/tests/metrics/integration_test/test_console_exporter.py

@@ -0,0 +1,37 @@
+# Copyright The OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from unittest import TestCase
+
+from opentelemetry import metrics
+from opentelemetry.sdk.metrics import MeterProvider
+from opentelemetry.sdk.metrics.export import (
+    ConsoleMetricExporter,
+    PeriodicExportingMetricReader,
+)
+
+
+class TestConsoleExporter(TestCase):
+    def test_console_exporter(self):
+
+        try:
+            exporter = ConsoleMetricExporter()
+            reader = PeriodicExportingMetricReader(exporter)
+            provider = MeterProvider(metric_readers=[reader])
+            metrics.set_meter_provider(provider)
+            meter = metrics.get_meter(__name__)
+            counter = meter.create_counter("test")
+            counter.add(1)
+        except Exception as error:
+            self.fail(f"Unexpected exception {error} raised")