[BUG] Behavior difference for an empty endpointUrl when upgrading from v1 to v2 #1890

channels/applicationinsights-channel-js/Tests/Unit/src/Sender.tests.ts

@@ -2,7 +2,7 @@ import { AITestClass } from "@microsoft/ai-test-framework";
 import { Sender } from "../../../src/Sender";
 import { createOfflineListener, IOfflineListener } from '../../../src/Offline';
 import { EnvelopeCreator } from '../../../src/EnvelopeCreator';
-import { Exception, CtxTagKeys, Util } from "@microsoft/applicationinsights-common";
+import { Exception, CtxTagKeys, Util, DEFAULT_BREEZE_ENDPOINT, DEFAULT_BREEZE_PATH } from "@microsoft/applicationinsights-common";
 import { ITelemetryItem, AppInsightsCore, ITelemetryPlugin, DiagnosticLogger, NotificationManager, SendRequestReason, _InternalMessageId, LoggingSeverity, getGlobalInst, getGlobal } from "@microsoft/applicationinsights-core-js";
 
 export class SenderTests extends AITestClass {
@@ -55,6 +55,31 @@ export class SenderTests extends AITestClass {
             }
         });
 
+        this.testCase({
+            name: "Channel Config: Validate empty endpointURL falls back to the default",
+            test: () => {
+                this._sender.initialize(
+                    {
+                        instrumentationKey: 'abc',
+                        maxBatchInterval: 123,
+                        endpointUrl: '',
+                        maxBatchSizeInBytes: 654,
+                        extensionConfig: {
+                            [this._sender.identifier]: {
+                                maxBatchSizeInBytes: 456
+                            }
+                        }
+
+                    }, new AppInsightsCore(), []
+                );
+
+                QUnit.assert.equal(123, this._sender._senderConfig.maxBatchInterval(), 'Channel config can be set from root config (maxBatchInterval)');
+                QUnit.assert.equal(DEFAULT_BREEZE_ENDPOINT + DEFAULT_BREEZE_PATH, this._sender._senderConfig.endpointUrl(), 'Channel config can be set from root config (endpointUrl)');
+                QUnit.assert.notEqual(654, this._sender._senderConfig.maxBatchSizeInBytes(), 'Channel config does not equal root config option if extensionConfig field is also set');
+                QUnit.assert.equal(456, this._sender._senderConfig.maxBatchSizeInBytes(), 'Channel config prioritizes extensionConfig over root config');
+            }
+        });
+
         this.testCase({
             name: "processTelemetry can be called with optional fields undefined",
             useFakeTimers: true,

channels/applicationinsights-channel-js/src/Sender.ts

@@ -218,9 +218,17 @@ export class Sender extends BaseTelemetryPlugin implements IChannelControlsAI {
                 _evtNamespace = mergeEvtNamespace(createUniqueNamespace("Sender"), core.evtNamespace && core.evtNamespace());
                 _offlineListener = createOfflineListener(_evtNamespace);
 
+                // TODO v3.x: Change the ISenderConfig to not be function calls
                 const defaultConfig = _getDefaultAppInsightsChannelConfig();
                 objForEachKey(defaultConfig, (field, value) => {
-                    _self._senderConfig[field] = () => ctx.getConfig(identifier, field, value());
+                    _self._senderConfig[field] = () => {
+                        let theValue = ctx.getConfig(identifier, field, value())
+                        if (!theValue && field === "endpointUrl") {
+                            // Use the default value (handles empty string in the configuration)
+                            theValue = value();
+                        }
+                        return theValue;
+                    }
                 });
 
                 _self._buffer = (_self._senderConfig.enableSessionStorageBuffer() && utlCanUseSessionStorage())