refactor: formalize Detector interface

open-telemetry · Apr 1, 2020 · db0df52 · db0df52
1 parent a2c936f
commit db0df52
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Showing 7 changed files with 38 additions and 11 deletions.
diff --git a/packages/opentelemetry-resources/src/Resource.ts b/packages/opentelemetry-resources/src/Resource.ts
@@ -16,6 +16,7 @@
 
 import { SDK_INFO } from '@opentelemetry/base';
 import { TELEMETRY_SDK_RESOURCE } from './constants';
+import { Labels } from './types';
 
 /**
  * A Resource describes the entity for which a signals (metrics or trace) are
@@ -67,7 +68,3 @@ export class Resource {
     return new Resource(mergedLabels);
   }
 }
-
-export interface Labels {
-  [key: string]: number | string | boolean;
-}
diff --git a/packages/opentelemetry-resources/src/index.ts b/packages/opentelemetry-resources/src/index.ts
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
-export { Resource, Labels } from './Resource';
+export * from './Resource';
 export * from './platform';
 export * from './constants';
+export * from './types';
diff --git a/packages/opentelemetry-resources/src/platform/node/detect-resources.ts b/packages/opentelemetry-resources/src/platform/node/detect-resources.ts
@@ -16,8 +16,9 @@
 
 import { Resource } from '../../Resource';
 import { envDetector, awsEc2Detector, gcpDetector } from './detectors';
+import { Detector } from '../../types';
 
-const DETECTORS = [envDetector, awsEc2Detector, gcpDetector];
+const DETECTORS: Array<Detector> = [envDetector, awsEc2Detector, gcpDetector];
 
 /**
  * Runs all resource detectors and returns the results merged into a single

diff --git a/packages/opentelemetry-resources/src/platform/node/detectors/AwsEc2Detector.ts b/packages/opentelemetry-resources/src/platform/node/detectors/AwsEc2Detector.ts
@@ -17,13 +17,14 @@
 import * as http from 'http';
 import { Resource } from '../../../Resource';
 import { CLOUD_RESOURCE, HOST_RESOURCE } from '../../../constants';
+import { Detector } from '../../../types';
 
 /**
  * The AwsEc2Detector can be used to detect if a process is running in AWS EC2
  * and return a {@link Resource} populated with metadata about the EC2
  * instance. Returns an empty Resource if detection fails.
  */
-class AwsEc2Detector {
+class AwsEc2Detector implements Detector {
   readonly AWS_INSTANCE_IDENTITY_DOCUMENT_URI =
     'http://169.254.169.254/latest/dynamic/instance-identity/document';
 

diff --git a/packages/opentelemetry-resources/src/platform/node/detectors/EnvDetector.ts b/packages/opentelemetry-resources/src/platform/node/detectors/EnvDetector.ts
@@ -14,13 +14,14 @@
  * limitations under the License.
  */
 
-import { Resource, Labels } from '../../../Resource';
+import { Resource } from '../../../Resource';
+import { Detector, Labels } from '../../../types';
 
 /**
  * EnvDetector can be used to detect the presence of and create a Resource
  * from the OTEL_RESOURCE_LABELS environment variable.
  */
-class EnvDetector {
+class EnvDetector implements Detector {
   // Type, label keys, and label values should not exceed 256 characters.
   private readonly _MAX_LENGTH = 255;
 

diff --git a/packages/opentelemetry-resources/src/platform/node/detectors/GcpDetector.ts b/packages/opentelemetry-resources/src/platform/node/detectors/GcpDetector.ts
@@ -16,7 +16,8 @@
 
 import * as os from 'os';
 import * as gcpMetadata from 'gcp-metadata';
-import { Resource, Labels } from '../../../Resource';
+import { Resource } from '../../../Resource';
+import { Detector, Labels } from '../../../types';
 import {
   CLOUD_RESOURCE,
   HOST_RESOURCE,
@@ -29,7 +30,7 @@ import {
  * Cloud Platofrm and return a {@link Resource} populated with metadata about
  * the instance. Returns an empty Resource if detection fails.
  */
-class GcpDetector {
+class GcpDetector implements Detector {
   async detect(): Promise<Resource> {
     if (!(await gcpMetadata.isAvailable())) return Resource.empty();
 

diff --git a/packages/opentelemetry-resources/src/types.ts b/packages/opentelemetry-resources/src/types.ts
@@ -0,0 +1,25 @@
+/**
+ * Copyright 2020, 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 { Resource } from './Resource';
+
+export interface Labels {
+  [key: string]: number | string | boolean;
+}
+
+export interface Detector {
+  detect(): Promise<Resource>;
+}