feat(trace-otlp-http-exporter): add compression env vars (#2796)

Co-authored-by: legendecas <legendecas@gmail.com>
Co-authored-by: Valentin Marchaud <contact@vmarchaud.fr>

packages/exporter-trace-otlp-http/src/platform/node/OTLPExporterNodeBase.ts

@@ -21,7 +21,7 @@ import { OTLPExporterBase } from '../../OTLPExporterBase';
 import { OTLPExporterNodeConfigBase, CompressionAlgorithm } from './types';
 import * as otlpTypes from '../../types';
 import { parseHeaders } from '../../util';
-import { createHttpAgent, sendWithHttp } from './util';
+import { createHttpAgent, sendWithHttp, configureCompression } from './util';
 import { diag } from '@opentelemetry/api';
 import { getEnv, baggageUtils } from '@opentelemetry/core';
 
@@ -53,7 +53,7 @@ export abstract class OTLPExporterNodeBase<
       baggageUtils.parseKeyPairsIntoRecord(getEnv().OTEL_EXPORTER_OTLP_HEADERS)
     );
     this.agent = createHttpAgent(config);
-    this.compression = config.compression || CompressionAlgorithm.NONE;
+    this.compression = configureCompression(config.compression);
   }
 
   onInit(_config: OTLPExporterNodeConfigBase): void {}

packages/exporter-trace-otlp-http/src/platform/node/util.ts

@@ -23,6 +23,7 @@ import { OTLPExporterNodeBase } from './OTLPExporterNodeBase';
 import { OTLPExporterNodeConfigBase } from '.';
 import { diag } from '@opentelemetry/api';
 import { CompressionAlgorithm } from './types';
+import { getEnv } from '@opentelemetry/core';
 
 let gzip: zlib.Gzip | undefined;
 
@@ -131,3 +132,12 @@ export function createHttpAgent(
     return undefined;
   }
 }
+
+export function configureCompression(compression: CompressionAlgorithm | undefined): CompressionAlgorithm {
+  if (compression) {
+    return compression;
+  } else {
+    const definedCompression = getEnv().OTEL_EXPORTER_OTLP_TRACES_COMPRESSION || getEnv().OTEL_EXPORTER_OTLP_COMPRESSION;
+    return definedCompression === CompressionAlgorithm.GZIP ? CompressionAlgorithm.GZIP : CompressionAlgorithm.NONE;
+  }
+}

packages/exporter-trace-otlp-http/test/node/CollectorTraceExporter.test.ts

@@ -112,6 +112,20 @@ describe('OTLPTraceExporter - node with json over http', () => {
       envSource.OTEL_EXPORTER_OTLP_TRACES_HEADERS = '';
       envSource.OTEL_EXPORTER_OTLP_HEADERS = '';
     });
+    it('should use compression defined via env', () => {
+      envSource.OTEL_EXPORTER_OTLP_COMPRESSION = 'gzip';
+      const collectorExporter = new OTLPTraceExporter();
+      assert.strictEqual(collectorExporter.compression, 'gzip');
+      envSource.OTEL_EXPORTER_OTLP_COMPRESSION = '';
+    });
+    it('should override global compression config with signal compression defined via env', () => {
+      envSource.OTEL_EXPORTER_OTLP_COMPRESSION = 'foo';
+      envSource.OTEL_EXPORTER_OTLP_TRACES_COMPRESSION = 'gzip';
+      const collectorExporter = new OTLPTraceExporter();
+      assert.strictEqual(collectorExporter.compression, 'gzip');
+      envSource.OTEL_EXPORTER_OTLP_COMPRESSION = '';
+      envSource.OTEL_EXPORTER_OTLP_TRACES_COMPRESSION = '';
+    });
   });
 
   describe('export', () => {

packages/exporter-trace-otlp-http/test/node/utils.test.ts

@@ -0,0 +1,40 @@
+/*
+ * 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
+ *
+ *      https://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.
+ */
+
+import * as assert from 'assert';
+import { CompressionAlgorithm} from '../../src/platform/node/types';
+import { configureCompression} from '../../src/platform/node/util';
+
+describe('configureCompression', () => {
+  const envSource = process.env;
+  it('should return none for compression', () => {
+    const compression = CompressionAlgorithm.NONE;
+    assert.strictEqual(configureCompression(compression), CompressionAlgorithm.NONE);
+  });
+  it('should return gzip compression defined via env', () => {
+    envSource.OTEL_EXPORTER_OTLP_TRACES_COMPRESSION = 'gzip';
+    assert.strictEqual(configureCompression(undefined),CompressionAlgorithm.GZIP);
+    delete envSource.OTEL_EXPORTER_OTLP_TRACES_COMPRESSION;
+  });
+  it('should return none for compression defined via env', () => {
+    envSource.OTEL_EXPORTER_OTLP_TRACES_COMPRESSION = 'none';
+    assert.strictEqual(configureCompression(undefined),CompressionAlgorithm.NONE);
+    delete envSource.OTEL_EXPORTER_OTLP_TRACES_COMPRESSION;
+  });
+  it('should return none for compression when no compression is set', () => {
+    assert.strictEqual(configureCompression(undefined),CompressionAlgorithm.NONE);
+  });
+});

packages/opentelemetry-core/src/utils/environment.ts

@@ -84,6 +84,9 @@ export type ENVIRONMENT = {
   OTEL_TRACES_EXPORTER?: string;
   OTEL_TRACES_SAMPLER_ARG?: string;
   OTEL_TRACES_SAMPLER?: string;
+  OTEL_EXPORTER_OTLP_COMPRESSION?: string,
+  OTEL_EXPORTER_OTLP_TRACES_COMPRESSION?: string,
+  OTEL_EXPORTER_OTLP_METRICS_COMPRESSION?: string
 } & ENVIRONMENT_NUMBERS &
   ENVIRONMENT_LISTS;
 
@@ -135,6 +138,9 @@ export const DEFAULT_ENVIRONMENT: Required<ENVIRONMENT> = {
   OTEL_TRACES_EXPORTER: 'none',
   OTEL_TRACES_SAMPLER: TracesSamplerValues.ParentBasedAlwaysOn,
   OTEL_TRACES_SAMPLER_ARG: '',
+  OTEL_EXPORTER_OTLP_COMPRESSION: '',
+  OTEL_EXPORTER_OTLP_TRACES_COMPRESSION: '',
+  OTEL_EXPORTER_OTLP_METRICS_COMPRESSION: ''
 };
 
 /**