cleanup OTLP exporter compression options, add tests

exporter/opentelemetry-exporter-otlp/src/opentelemetry/exporter/otlp/__init__.py

@@ -22,20 +22,14 @@
 The **OTLP Span Exporter** allows to export `OpenTelemetry`_ traces to the
 `OTLP`_ collector.
 
+You can configure the exporter with the following environment variables
+
+- :envvar:`OTEL_EXPORTER_OTLP_SPAN_COMPRESSION`
+- :envvar:`OTEL_EXPORTER_OTLP_COMPRESSION`
 
 .. _OTLP: https://github.com/open-telemetry/opentelemetry-collector/
 .. _OpenTelemetry: https://github.com/open-telemetry/opentelemetry-python/
 
-.. envvar:: OTEL_EXPORTER_OTLP_COMPRESSION
-
-The :envvar:`OTEL_EXPORTER_OTLP_COMPRESSION` environment variable allows a
-compression algorithm to be passed to the OTLP exporter. The compression
-algorithms that are supported include gzip and no compression. The value should
-be in the format of a string "gzip" for gzip compression, and no value specified
-if no compression is the desired choice.
-Additional details are available `in the specification
-<https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/protocol/exporter.md#opentelemetry-protocol-exporter>`_.
-
 .. code:: python
 
     from opentelemetry import trace

exporter/opentelemetry-exporter-otlp/src/opentelemetry/exporter/otlp/exporter.py

@@ -14,7 +14,6 @@
 
 """OTLP Exporter"""
 
-import enum
 import logging
 from abc import ABC, abstractmethod
 from collections.abc import Mapping, Sequence
@@ -40,6 +39,7 @@
 from opentelemetry.proto.resource.v1.resource_pb2 import Resource
 from opentelemetry.sdk.environment_variables import (
     OTEL_EXPORTER_OTLP_CERTIFICATE,
+    OTEL_EXPORTER_OTLP_COMPRESSION,
     OTEL_EXPORTER_OTLP_ENDPOINT,
     OTEL_EXPORTER_OTLP_HEADERS,
     OTEL_EXPORTER_OTLP_INSECURE,
@@ -54,9 +54,22 @@
 ExportServiceRequestT = TypeVar("ExportServiceRequestT")
 ExportResultT = TypeVar("ExportResultT")
 
+_ENVIRON_TO_COMPRESSION = {
+    None: None,
+    "gzip": Compression.Gzip,
+    "deflate": Compression.Deflate,
+}
 
-class OTLPCompression(enum.Enum):
-    gzip = "gzip"
+
+def environ_to_compression(environ_key: str) -> Optional[Compression]:
+    environ_value = environ.get(environ_key)
+    if environ_value not in _ENVIRON_TO_COMPRESSION:
+        raise Exception(
+            'Invalid value "{}" for compression envvar {}'.format(
+                environ_value, environ_key
+            )
+        )
+    return _ENVIRON_TO_COMPRESSION[environ_value]
 
 
 def _translate_key_values(key: Text, value: Any) -> KeyValue:
@@ -87,7 +100,7 @@ def _translate_key_values(key: Text, value: Any) -> KeyValue:
     return KeyValue(key=key, value=any_value)
 
 
-def _get_resource_data(
+def get_resource_data(
     sdk_resource_instrumentation_library_data: Dict[
         SDKResource, ResourceDataT
     ],
@@ -160,7 +173,7 @@ def __init__(
         credentials: Optional[ChannelCredentials] = None,
         headers: Optional[Sequence] = None,
         timeout: Optional[int] = None,
-        compression: str = None,
+        compression: Optional[Compression] = None,
     ):
         super().__init__()
 
@@ -187,30 +200,15 @@ def __init__(
         )
         self._collector_span_kwargs = None
 
-        if compression is None:
-            compression_algorithm = Compression.NoCompression
-        elif (
-            compression in OTLPCompression._value2member_map_
-            and OTLPCompression(compression) is OTLPCompression.gzip
-        ):
-            compression_algorithm = Compression.Gzip
-        else:
-            compression_str = environ.get(OTEL_EXPORTER_OTLP_INSECURE)
-            if compression_str is None:
-                compression_algorithm = Compression.NoCompression
-            elif (
-                compression_str in OTLPCompression._value2member_map_
-                and OTLPCompression(compression_str) is OTLPCompression.gzip
-            ):
-                compression_algorithm = Compression.Gzip
-            else:
-                raise ValueError(
-                    "OTEL_EXPORTER_OTLP_COMPRESSION environment variable does not match gzip."
-                )
+        compression = (
+            environ_to_compression(OTEL_EXPORTER_OTLP_COMPRESSION)
+            if compression is None
+            else compression
+        ) or Compression.NoCompression
 
         if insecure:
             self._client = self._stub(
-                insecure_channel(endpoint, compression=compression_algorithm)
+                insecure_channel(endpoint, compression=compression)
             )
             return
 
@@ -226,9 +224,7 @@ def __init__(
                 environ.get(OTEL_EXPORTER_OTLP_CERTIFICATE)
             )
         self._client = self._stub(
-            secure_channel(
-                endpoint, credentials, compression=compression_algorithm
-            )
+            secure_channel(endpoint, credentials, compression=compression)
         )
 
     @abstractmethod

exporter/opentelemetry-exporter-otlp/src/opentelemetry/exporter/otlp/trace_exporter/__init__.py

@@ -17,13 +17,14 @@
 from os import environ
 from typing import Optional, Sequence
 
-from grpc import ChannelCredentials
+from grpc import ChannelCredentials, Compression
 
 from opentelemetry.exporter.otlp.exporter import (
     OTLPExporterMixin,
-    _get_resource_data,
     _load_credential_from_file,
     _translate_key_values,
+    environ_to_compression,
+    get_resource_data,
 )
 from opentelemetry.proto.collector.trace.v1.trace_service_pb2 import (
     ExportTraceServiceRequest,
@@ -40,6 +41,7 @@
 from opentelemetry.proto.trace.v1.trace_pb2 import Status
 from opentelemetry.sdk.environment_variables import (
     OTEL_EXPORTER_OTLP_SPAN_CERTIFICATE,
+    OTEL_EXPORTER_OTLP_SPAN_COMPRESSION,
     OTEL_EXPORTER_OTLP_SPAN_ENDPOINT,
     OTEL_EXPORTER_OTLP_SPAN_HEADERS,
     OTEL_EXPORTER_OTLP_SPAN_INSECURE,
@@ -80,6 +82,7 @@ def __init__(
         credentials: Optional[ChannelCredentials] = None,
         headers: Optional[Sequence] = None,
         timeout: Optional[int] = None,
+        compression: Optional[Compression] = None,
     ):
         if insecure is None:
             insecure = environ.get(OTEL_EXPORTER_OTLP_SPAN_INSECURE)
@@ -97,6 +100,12 @@ def __init__(
             int(environ_timeout) if environ_timeout is not None else None
         )
 
+        compression = (
+            environ_to_compression(OTEL_EXPORTER_OTLP_SPAN_COMPRESSION)
+            if compression is None
+            else compression
+        )
+
         super().__init__(
             **{
                 "endpoint": endpoint
@@ -106,6 +115,7 @@ def __init__(
                 "headers": headers
                 or environ.get(OTEL_EXPORTER_OTLP_SPAN_HEADERS),
                 "timeout": timeout or environ_timeout,
+                "compression": compression,
             }
         )
 
@@ -274,7 +284,7 @@ def _translate_data(
             ].spans.append(CollectorSpan(**self._collector_span_kwargs))
 
         return ExportTraceServiceRequest(
-            resource_spans=_get_resource_data(
+            resource_spans=get_resource_data(
                 sdk_resource_instrumentation_library_spans,
                 ResourceSpans,
                 "spans",

exporter/opentelemetry-exporter-otlp/tests/test_otlp_exporter_mixin.py

@@ -0,0 +1,27 @@
+from unittest import TestCase
+from unittest.mock import patch
+
+from grpc import Compression
+
+from opentelemetry.exporter.otlp.exporter import environ_to_compression
+
+
+class TestOTLPExporterMixin(TestCase):
+    def test_environ_to_compression(self):
+        with patch.dict(
+            "os.environ",
+            {
+                "test_gzip": "gzip",
+                "test_deflate": "deflate",
+                "test_invalid": "some invalid compression",
+            },
+        ):
+            self.assertEqual(
+                environ_to_compression("test_gzip"), Compression.Gzip
+            )
+            self.assertEqual(
+                environ_to_compression("test_deflate"), Compression.Deflate
+            )
+            self.assertIsNone(environ_to_compression("missing_key"),)
+            with self.assertRaises(Exception):
+                environ_to_compression("test_invalid")

exporter/opentelemetry-exporter-otlp/tests/test_otlp_trace_exporter.py

@@ -20,7 +20,7 @@
 
 from google.protobuf.duration_pb2 import Duration
 from google.rpc.error_details_pb2 import RetryInfo
-from grpc import ChannelCredentials, StatusCode, server
+from grpc import ChannelCredentials, Compression, StatusCode, server
 
 from opentelemetry.exporter.otlp.trace_exporter import OTLPSpanExporter
 from opentelemetry.proto.collector.trace.v1.trace_service_pb2 import (
@@ -46,7 +46,9 @@
 from opentelemetry.proto.trace.v1.trace_pb2 import Span as OTLPSpan
 from opentelemetry.proto.trace.v1.trace_pb2 import Status
 from opentelemetry.sdk.environment_variables import (
+    OTEL_EXPORTER_OTLP_COMPRESSION,
     OTEL_EXPORTER_OTLP_SPAN_CERTIFICATE,
+    OTEL_EXPORTER_OTLP_SPAN_COMPRESSION,
     OTEL_EXPORTER_OTLP_SPAN_ENDPOINT,
     OTEL_EXPORTER_OTLP_SPAN_HEADERS,
     OTEL_EXPORTER_OTLP_SPAN_TIMEOUT,
@@ -174,6 +176,7 @@ def tearDown(self):
             + "/fixtures/test.cert",
             OTEL_EXPORTER_OTLP_SPAN_HEADERS: "key1=value1,key2=value2",
             OTEL_EXPORTER_OTLP_SPAN_TIMEOUT: "10",
+            OTEL_EXPORTER_OTLP_SPAN_COMPRESSION: "gzip",
         },
     )
     @patch("opentelemetry.exporter.otlp.exporter.OTLPExporterMixin.__init__")
@@ -186,6 +189,7 @@ def test_env_variables(self, mock_exporter_mixin):
         self.assertEqual(kwargs["endpoint"], "collector:4317")
         self.assertEqual(kwargs["headers"], "key1=value1,key2=value2")
         self.assertEqual(kwargs["timeout"], 10)
+        self.assertEqual(kwargs["compression"], Compression.Gzip)
         self.assertIsNotNone(kwargs["credentials"])
         self.assertIsInstance(kwargs["credentials"], ChannelCredentials)
 
@@ -220,6 +224,57 @@ def test_otlp_headers_from_env(self, mock_ssl_channel, mock_secure):
             exporter._headers, (("key3", "value3"), ("key4", "value4"))
         )
 
+    # pylint: disable=no-self-use
+    def test_otlp_compression_from_env(self):
+        # Specifying kwarg should take precedence over env
+        with patch(
+            "opentelemetry.exporter.otlp.exporter.insecure_channel"
+        ) as mock_insecure_channel, patch.dict(
+            "os.environ", {OTEL_EXPORTER_OTLP_COMPRESSION: "gzip"}
+        ):
+            OTLPSpanExporter(
+                insecure=True, compression=Compression.NoCompression
+            )
+            mock_insecure_channel.assert_called_once_with(
+                "localhost:4317", compression=Compression.NoCompression
+            )
+
+        # No env or kwarg should be NoCompression
+        with patch(
+            "opentelemetry.exporter.otlp.exporter.insecure_channel"
+        ) as mock_insecure_channel, patch.dict("os.environ", {}):
+            OTLPSpanExporter(insecure=True)
+            mock_insecure_channel.assert_called_once_with(
+                "localhost:4317", compression=Compression.NoCompression
+            )
+
+        # Just OTEL_EXPORTER_OTLP_COMPRESSION should work
+        with patch(
+            "opentelemetry.exporter.otlp.exporter.insecure_channel"
+        ) as mock_insecure_channel, patch.dict(
+            "os.environ", {OTEL_EXPORTER_OTLP_COMPRESSION: "deflate"}
+        ):
+            OTLPSpanExporter(insecure=True)
+            mock_insecure_channel.assert_called_once_with(
+                "localhost:4317", compression=Compression.Deflate
+            )
+
+        # OTEL_EXPORTER_OTLP_SPAN_COMPRESSION as higher priority than
+        # OTEL_EXPORTER_OTLP_COMPRESSION
+        with patch(
+            "opentelemetry.exporter.otlp.exporter.insecure_channel"
+        ) as mock_insecure_channel, patch.dict(
+            "os.environ",
+            {
+                OTEL_EXPORTER_OTLP_COMPRESSION: "deflate",
+                OTEL_EXPORTER_OTLP_SPAN_COMPRESSION: "gzip",
+            },
+        ):
+            OTLPSpanExporter(insecure=True)
+            mock_insecure_channel.assert_called_once_with(
+                "localhost:4317", compression=Compression.Gzip
+            )
+
     @patch("opentelemetry.exporter.otlp.exporter.ssl_channel_credentials")
     @patch("opentelemetry.exporter.otlp.exporter.secure_channel")
     # pylint: disable=unused-argument

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

@@ -33,14 +33,39 @@
 OTEL_EXPORTER_OTLP_PROTOCOL = "OTEL_EXPORTER_OTLP_PROTOCOL"
 OTEL_EXPORTER_OTLP_CERTIFICATE = "OTEL_EXPORTER_OTLP_CERTIFICATE"
 OTEL_EXPORTER_OTLP_HEADERS = "OTEL_EXPORTER_OTLP_HEADERS"
+
 OTEL_EXPORTER_OTLP_COMPRESSION = "OTEL_EXPORTER_OTLP_COMPRESSION"
+"""
+.. envvar:: OTEL_EXPORTER_OTLP_COMPRESSION
+
+Specifies a gRPC compression method to be used in the OTLP exporters.
+Possible values are:
+
+- ``gzip`` corresponding to `grpc.Compression.Gzip`.
+- ``deflate`` corresponding to `grpc.Compression.Deflate`.
+
+If no ``OTEL_EXPORTER_OTLP_*COMPRESSION`` environment variable is present or
+``compression`` argument passed to the exporter, the default
+`grpc.Compression.NoCompression` will be used. Additional details are
+available `in the specification
+<https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/protocol/exporter.md#opentelemetry-protocol-exporter>`_.
+"""
+
 OTEL_EXPORTER_OTLP_TIMEOUT = "OTEL_EXPORTER_OTLP_TIMEOUT"
 OTEL_EXPORTER_OTLP_ENDPOINT = "OTEL_EXPORTER_OTLP_ENDPOINT"
 OTEL_EXPORTER_OTLP_SPAN_ENDPOINT = "OTEL_EXPORTER_OTLP_SPAN_ENDPOINT"
 OTEL_EXPORTER_OTLP_SPAN_PROTOCOL = "OTEL_EXPORTER_OTLP_SPAN_PROTOCOL"
 OTEL_EXPORTER_OTLP_SPAN_CERTIFICATE = "OTEL_EXPORTER_OTLP_SPAN_CERTIFICATE"
 OTEL_EXPORTER_OTLP_SPAN_HEADERS = "OTEL_EXPORTER_OTLP_SPAN_HEADERS"
+
 OTEL_EXPORTER_OTLP_SPAN_COMPRESSION = "OTEL_EXPORTER_OTLP_SPAN_COMPRESSION"
+"""
+.. envvar:: OTEL_EXPORTER_OTLP_SPAN_COMPRESSION
+
+Same as :envvar:`OTEL_EXPORTER_OTLP_COMPRESSION`, but takes higher precedence
+for the OTLP span exporter.
+"""
+
 OTEL_EXPORTER_OTLP_SPAN_TIMEOUT = "OTEL_EXPORTER_OTLP_SPAN_TIMEOUT"
 OTEL_EXPORTER_JAEGER_INSECURE = "OTEL_EXPORTER_JAEGER_INSECURE"
 OTEL_EXPORTER_JAEGER_CERTIFICATE = "OTEL_EXPORTER_JAEGER_CERTIFICATE"