fix: [OTLP] detect http/https protocol from parsedUrl.protocol (#9028)

* detect http/https protocol from prasedUrl.protocol

* privatize the attribute this.transport

* fix ci failures

* fall back on https

* Update packages/dd-trace/src/opentelemetry/otlp/otlp_http_exporter_base.js

Co-authored-by: Ruben Bridgewater <ruben@bridgewater.de>

* added telemetry test cases

---------

Co-authored-by: Ruben Bridgewater <ruben@bridgewater.de>

Author: ida613

packages/dd-trace/src/opentelemetry/otlp/otlp_http_exporter_base.js

@@ -1,7 +1,8 @@
 'use strict'
 
-const http = require('http')
-const { URL } = require('url')
+const http = require('node:http')
+const https = require('node:https')
+const { URL } = require('node:url')
 const log = require('../../log')
 const telemetryMetrics = require('../../telemetry/metrics')
 
@@ -16,6 +17,8 @@ const tracerMetrics = telemetryMetrics.manager.namespace('tracers')
  * @class OtlpHttpExporterBase
  */
 class OtlpHttpExporterBase {
+  #transport = https
+
   /**
    * Creates a new OtlpHttpExporterBase instance.
    *
@@ -45,7 +48,7 @@ class OtlpHttpExporterBase {
     this.setUrl(url)
 
     this.telemetryTags = [
-      'protocol:http',
+      `protocol:${this.#transport === https ? 'https' : 'http'}`,
       `encoding:${isJson ? 'json' : 'protobuf'}`,
     ]
   }
@@ -81,7 +84,7 @@ class OtlpHttpExporterBase {
       },
     }
 
-    const req = http.request(options, (res) => {
+    const req = this.#transport.request(options, (res) => {
       let data = ''
 
       res.on('data', (chunk) => {
@@ -124,6 +127,10 @@ class OtlpHttpExporterBase {
     this.options.hostname = parsedUrl.hostname
     this.options.port = parsedUrl.port
     this.options.path = parsedUrl.pathname + parsedUrl.search
+    this.#transport = parsedUrl.protocol === 'http:' ? http : https
+    if (this.telemetryTags !== undefined) {
+      this.telemetryTags[0] = `protocol:${this.#transport === https ? 'https' : 'http'}`
+    }
   }
 
   /**

packages/dd-trace/test/opentelemetry/traces.spec.js

@@ -1,7 +1,8 @@
 'use strict'
 
 const assert = require('assert')
-const http = require('http')
+const http = require('node:http')
+const https = require('node:https')
 
 const { describe, it, beforeEach, afterEach } = require('mocha')
 const sinon = require('sinon')
@@ -844,6 +845,18 @@ describe('OpenTelemetry Traces', () => {
   })
 
   describe('Telemetry Metrics', () => {
+    it('sets protocol:http tag for http:// endpoint', () => {
+      const exporter = new OtlpHttpTraceExporter('http://collector.example/v1/traces', {}, 1000, {})
+
+      assert.ok(exporter.telemetryTags.includes('protocol:http'))
+    })
+
+    it('sets protocol:https tag for https:// endpoint', () => {
+      const exporter = new OtlpHttpTraceExporter('https://collector.example/v1/traces', {}, 1000, {})
+
+      assert.ok(exporter.telemetryTags.includes('protocol:https'))
+    })
+
     it('tracks telemetry metrics for exported traces', () => {
       const telemetryMetrics = {
         manager: { namespace: sinon.stub().returns({ count: sinon.stub().returns({ inc: sinon.spy() }) }) },
@@ -887,5 +900,39 @@ describe('OpenTelemetry Traces', () => {
 
       assert.strictEqual(exporter.options.path, '/v1/traces?token=abc')
     })
+
+    it('selects http transport for http:// URLs', () => {
+      const exporter = new OtlpHttpTraceExporter('http://collector.example/v1/traces', {}, 1000, {})
+      const mockReq = { write: () => {}, end: () => {}, on: () => mockReq, once: () => mockReq }
+      const httpStub = sinon.stub(http, 'request').returns(mockReq)
+      sinon.stub(https, 'request').returns(mockReq)
+
+      exporter.sendPayload(Buffer.from('{}'), () => {})
+
+      assert.ok(httpStub.calledOnce, 'http.request should have been called')
+    })
+
+    it('selects https transport for https:// URLs', () => {
+      const exporter = new OtlpHttpTraceExporter('https://collector.example/v1/traces', {}, 1000, {})
+      const mockReq = { write: () => {}, end: () => {}, on: () => mockReq, once: () => mockReq }
+      sinon.stub(http, 'request').returns(mockReq)
+      const httpsStub = sinon.stub(https, 'request').returns(mockReq)
+
+      exporter.sendPayload(Buffer.from('{}'), () => {})
+
+      assert.ok(httpsStub.calledOnce, 'https.request should have been called')
+    })
+
+    it('switches transport when setUrl is called with a different scheme', () => {
+      const exporter = new OtlpHttpTraceExporter('http://collector.example/v1/traces', {}, 1000, {})
+      const mockReq = { write: () => {}, end: () => {}, on: () => mockReq, once: () => mockReq }
+      sinon.stub(http, 'request').returns(mockReq)
+      const httpsStub = sinon.stub(https, 'request').returns(mockReq)
+
+      exporter.setUrl('https://secure-collector.example/v1/traces')
+      exporter.sendPayload(Buffer.from('{}'), () => {})
+
+      assert.ok(httpsStub.calledOnce, 'https.request should have been called after switching to https')
+    })
   })
 })