Resources sdk (open-telemetry#464)

Moving resources to the SDK, as per the specification.

Modifying the values it accepts to int, float, str, and bool, to match the spec.

Introducing an empty resource. To short-circuit the common empty situation.

Author: mauriciovasquezbernal

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

@@ -19,6 +19,7 @@
 from opentelemetry import metrics as metrics_api
 from opentelemetry.sdk.metrics.export.aggregate import Aggregator
 from opentelemetry.sdk.metrics.export.batcher import Batcher, UngroupedBatcher
+from opentelemetry.sdk.resources import Resource
 from opentelemetry.sdk.util.instrumentation import InstrumentationInfo
 from opentelemetry.util import time_ns
 
@@ -289,12 +290,16 @@ class Meter(metrics_api.Meter):
     """
 
     def __init__(
-        self, instrumentation_info: "InstrumentationInfo", stateful: bool,
+        self,
+        instrumentation_info: "InstrumentationInfo",
+        stateful: bool,
+        resource: Resource = Resource.create_empty(),
     ):
         self.instrumentation_info = instrumentation_info
         self.metrics = set()
         self.observers = set()
         self.batcher = UngroupedBatcher(stateful)
+        self.resource = resource
 
     def collect(self) -> None:
         """Collects all the metrics created with this `Meter` for export.
@@ -400,6 +405,11 @@ def get_label_set(self, labels: Dict[str, str]):
 
 
 class MeterProvider(metrics_api.MeterProvider):
+    def __init__(
+        self, resource: Resource = Resource.create_empty(),
+    ):
+        self.resource = resource
+
     def get_meter(
         self,
         instrumenting_module_name: str,
@@ -413,4 +423,5 @@ def get_meter(
                 instrumenting_module_name, instrumenting_library_version
             ),
             stateful=stateful,
+            resource=self.resource,
         )

opentelemetry-api/src/opentelemetry/resources/py.typed

@@ -12,33 +12,42 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import opentelemetry.resources as resources
+import typing
 
+LabelValue = typing.Union[str, bool, int, float]
+Labels = typing.Dict[str, LabelValue]
 
-class Resource(resources.Resource):
-    def __init__(self, labels):
-        self._labels = labels
+
+class Resource:
+    def __init__(self, labels: Labels):
+        self._labels = labels.copy()
 
     @staticmethod
-    def create(labels):
+    def create(labels: Labels) -> "Resource":
+        if not labels:
+            return _EMPTY_RESOURCE
         return Resource(labels)
 
+    @staticmethod
+    def create_empty() -> "Resource":
+        return _EMPTY_RESOURCE
+
     @property
-    def labels(self):
-        return self._labels
-
-    def merge(self, other):
-        if other is None:
-            return self
-        if not self._labels:
-            return other
-        merged_labels = self.labels.copy()
-        for key, value in other.labels.items():
+    def labels(self) -> Labels:
+        return self._labels.copy()
+
+    def merge(self, other: "Resource") -> "Resource":
+        merged_labels = self.labels
+        # pylint: disable=protected-access
+        for key, value in other._labels.items():
             if key not in merged_labels or merged_labels[key] == "":
                 merged_labels[key] = value
         return Resource(merged_labels)
 
     def __eq__(self, other: object) -> bool:
         if not isinstance(other, Resource):
             return False
-        return self.labels == other.labels
+        return self._labels == other._labels
+
+
+_EMPTY_RESOURCE = Resource({})

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

@@ -25,6 +25,7 @@
 from opentelemetry import context as context_api
 from opentelemetry import trace as trace_api
 from opentelemetry.sdk import util
+from opentelemetry.sdk.resources import Resource
 from opentelemetry.sdk.util import BoundedDict, BoundedList
 from opentelemetry.sdk.util.instrumentation import InstrumentationInfo
 from opentelemetry.trace import SpanContext, sampling
@@ -127,7 +128,7 @@ class Span(trace_api.Span):
             remote, null if this is a root span
         sampler: The sampler used to create this span
         trace_config: TODO
-        resource: TODO
+        resource: Entity producing telemetry
         attributes: The span's attributes to be exported
         events: Timestamped events to be exported
         links: Links to other spans to be exported
@@ -147,7 +148,7 @@ def __init__(
         parent: trace_api.ParentSpan = None,
         sampler: Optional[sampling.Sampler] = None,
         trace_config: None = None,  # TODO
-        resource: None = None,  # TODO
+        resource: None = None,
         attributes: types.Attributes = None,  # TODO
         events: Sequence[trace_api.Event] = None,  # TODO
         links: Sequence[trace_api.Link] = (),
@@ -486,6 +487,7 @@ def start_span(  # pylint: disable=too-many-locals
                 context=context,
                 parent=parent,
                 sampler=self.source.sampler,
+                resource=self.source.resource,
                 attributes=span_attributes,
                 span_processor=self.source._active_span_processor,  # pylint:disable=protected-access
                 kind=kind,
@@ -535,9 +537,11 @@ class TracerProvider(trace_api.TracerProvider):
     def __init__(
         self,
         sampler: sampling.Sampler = trace_api.sampling.ALWAYS_ON,
+        resource: Resource = Resource.create_empty(),
         shutdown_on_exit: bool = True,
     ):
         self._active_span_processor = MultiSpanProcessor()
+        self.resource = resource
         self.sampler = sampler
         self._atexit_handler = None
         if shutdown_on_exit:

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

@@ -16,10 +16,24 @@
 from unittest import mock
 
 from opentelemetry import metrics as metrics_api
-from opentelemetry.sdk import metrics
+from opentelemetry.sdk import metrics, resources
 from opentelemetry.sdk.metrics import export
 
 
+class TestMeterProvider(unittest.TestCase):
+    def test_resource(self):
+        resource = resources.Resource.create({})
+        meter_provider = metrics.MeterProvider(resource=resource)
+        meter = meter_provider.get_meter(__name__)
+        self.assertIs(meter.resource, resource)
+
+    def test_resource_empty(self):
+        meter_provider = metrics.MeterProvider()
+        meter = meter_provider.get_meter(__name__)
+        # pylint: disable=protected-access
+        self.assertIs(meter.resource, resources._EMPTY_RESOURCE)
+
+
 class TestMeter(unittest.TestCase):
     def test_extends_api(self):
         meter = metrics.MeterProvider().get_meter(__name__)
@@ -126,13 +140,16 @@ def test_record_batch_exists(self):
         self.assertEqual(handle.aggregator.current, 2.0)
 
     def test_create_metric(self):
-        meter = metrics.MeterProvider().get_meter(__name__)
+        resource = mock.Mock(spec=resources.Resource)
+        meter_provider = metrics.MeterProvider(resource=resource)
+        meter = meter_provider.get_meter(__name__)
         counter = meter.create_metric(
             "name", "desc", "unit", int, metrics.Counter, ()
         )
         self.assertIsInstance(counter, metrics.Counter)
         self.assertEqual(counter.value_type, int)
         self.assertEqual(counter.name, "name")
+        self.assertIs(counter.meter.resource, resource)
 
     def test_create_measure(self):
         meter = metrics.MeterProvider().get_meter(__name__)

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

@@ -12,12 +12,35 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# pylint: disable=protected-access
+
 import unittest
 
 from opentelemetry.sdk import resources
 
 
 class TestResources(unittest.TestCase):
+    def test_create(self):
+        labels = {
+            "service": "ui",
+            "version": 1,
+            "has_bugs": True,
+            "cost": 112.12,
+        }
+
+        resource = resources.Resource.create(labels)
+        self.assertIsInstance(resource, resources.Resource)
+        self.assertEqual(resource.labels, labels)
+
+        resource = resources.Resource.create_empty()
+        self.assertIs(resource, resources._EMPTY_RESOURCE)
+
+        resource = resources.Resource.create(None)
+        self.assertIs(resource, resources._EMPTY_RESOURCE)
+
+        resource = resources.Resource.create({})
+        self.assertIs(resource, resources._EMPTY_RESOURCE)
+
     def test_resource_merge(self):
         left = resources.Resource({"service": "ui"})
         right = resources.Resource({"host": "service-host"})
@@ -41,3 +64,22 @@ def test_resource_merge_empty_string(self):
             left.merge(right),
             resources.Resource({"service": "ui", "host": "service-host"}),
         )
+
+    def test_immutability(self):
+        labels = {
+            "service": "ui",
+            "version": 1,
+            "has_bugs": True,
+            "cost": 112.12,
+        }
+
+        labels_copy = labels.copy()
+
+        resource = resources.Resource.create(labels)
+        self.assertEqual(resource.labels, labels_copy)
+
+        resource.labels["has_bugs"] = False
+        self.assertEqual(resource.labels, labels_copy)
+
+        labels["cost"] = 999.91
+        self.assertEqual(resource.labels, labels_copy)

opentelemetry-sdk/tests/metrics/test_metrics.py

@@ -19,7 +19,7 @@
 from unittest import mock
 
 from opentelemetry import trace as trace_api
-from opentelemetry.sdk import trace
+from opentelemetry.sdk import resources, trace
 from opentelemetry.sdk.util.instrumentation import InstrumentationInfo
 from opentelemetry.trace import sampling
 from opentelemetry.trace.status import StatusCanonicalCode
@@ -364,6 +364,20 @@ def test_start_as_current_span_explicit(self):
             self.assertIs(tracer.get_current_span(), root)
             self.assertIsNotNone(child.end_time)
 
+    def test_explicit_span_resource(self):
+        resource = resources.Resource.create({})
+        tracer_provider = trace.TracerProvider(resource=resource)
+        tracer = tracer_provider.get_tracer(__name__)
+        span = tracer.start_span("root")
+        self.assertIs(span.resource, resource)
+
+    def test_default_span_resource(self):
+        tracer_provider = trace.TracerProvider()
+        tracer = tracer_provider.get_tracer(__name__)
+        span = tracer.start_span("root")
+        # pylint: disable=protected-access
+        self.assertIs(span.resource, resources._EMPTY_RESOURCE)
+
 
 class TestSpan(unittest.TestCase):
     def setUp(self):