fix(tracing-internal): Delay pageload transaction finish until document is interactive

Author: lforst

packages/core/src/tracing/hubextensions.ts

@@ -89,13 +89,22 @@ export function startIdleTransaction(
   onScope?: boolean,
   customSamplingContext?: CustomSamplingContext,
   heartbeatInterval?: number,
+  delayAutoFinishUntilSignal: boolean = false,
 ): IdleTransaction {
   // eslint-disable-next-line deprecation/deprecation
   const client = hub.getClient();
   const options: Partial<ClientOptions> = (client && client.getOptions()) || {};
 
   // eslint-disable-next-line deprecation/deprecation
-  let transaction = new IdleTransaction(transactionContext, hub, idleTimeout, finalTimeout, heartbeatInterval, onScope);
+  let transaction = new IdleTransaction(
+    transactionContext,
+    hub,
+    idleTimeout,
+    finalTimeout,
+    heartbeatInterval,
+    onScope,
+    delayAutoFinishUntilSignal,
+  );
   transaction = sampleTransaction(transaction, options, {
     parentSampled: transactionContext.parentSampled,
     transactionContext,

packages/core/src/tracing/idletransaction.ts

@@ -95,6 +95,8 @@ export class IdleTransaction extends Transaction {
 
   private _finishReason: (typeof IDLE_TRANSACTION_FINISH_REASONS)[number];
 
+  private _autoFinishAllowed: boolean;
+
   /**
    * @deprecated Transactions will be removed in v8. Use spans instead.
    */
@@ -113,6 +115,15 @@ export class IdleTransaction extends Transaction {
     private readonly _heartbeatInterval: number = TRACING_DEFAULTS.heartbeatInterval,
     // Whether or not the transaction should put itself on the scope when it starts and pop itself off when it ends
     private readonly _onScope: boolean = false,
+    /**
+     * When set to `true`, will disable the idle timeout (`_idleTimeout` option) and heartbeat mechanisms (`_heartbeatInterval`
+     * option) until the `sendAutoFinishSignal()` method is called. The final timeout mechanism (`_finalTimeout` option)
+     * will not be affected by this option, meaning the transaction will definitely be finished when the final timeout is
+     * reached, no matter what this option is configured to.
+     *
+     * Defaults to `false`.
+     */
+    delayAutoFinishUntilSignal: boolean = false,
   ) {
     super(transactionContext, _idleHub);
 
@@ -122,6 +133,7 @@ export class IdleTransaction extends Transaction {
     this._idleTimeoutCanceledPermanently = false;
     this._beforeFinishCallbacks = [];
     this._finishReason = IDLE_TRANSACTION_FINISH_REASONS[4];
+    this._autoFinishAllowed = !delayAutoFinishUntilSignal;
 
     if (_onScope) {
       // We set the transaction here on the scope so error events pick up the trace
@@ -131,7 +143,10 @@ export class IdleTransaction extends Transaction {
       _idleHub.getScope().setSpan(this);
     }
 
-    this._restartIdleTimeout();
+    if (!delayAutoFinishUntilSignal) {
+      this._restartIdleTimeout();
+    }
+
     setTimeout(() => {
       if (!this._finished) {
         this.setStatus('deadline_exceeded');
@@ -215,7 +230,7 @@ export class IdleTransaction extends Transaction {
   }
 
   /**
-   * Register a callback function that gets excecuted before the transaction finishes.
+   * Register a callback function that gets executed before the transaction finishes.
    * Useful for cleanup or if you want to add any additional spans based on current context.
    *
    * This is exposed because users have no other way of running something before an idle transaction
@@ -296,13 +311,24 @@ export class IdleTransaction extends Transaction {
     this._finishReason = reason;
   }
 
+  /**
+   * Permits the IdleTransaction to automatically end itself via the idle timeout and heartbeat mechanisms when the `delayAutoFinishUntilSignal` option was set to `true`.
+   */
+  public sendAutoFinishSignal(): void {
+    if (!this._autoFinishAllowed) {
+      DEBUG_BUILD && logger.log('[Tracing] Received finish signal for idle transaction.');
+      this._restartIdleTimeout();
+      this._autoFinishAllowed = true;
+    }
+  }
+
   /**
    * Restarts idle timeout, if there is no running idle timeout it will start one.
    */
   private _restartIdleTimeout(endTimestamp?: Parameters<IdleTransaction['end']>[0]): void {
     this.cancelIdleTimeout();
     this._idleTimeoutID = setTimeout(() => {
-      if (!this._finished && Object.keys(this.activities).length === 0) {
+      if (!this._finished && Object.keys(this.activities).length === 0 && this._autoFinishAllowed) {
         this._finishReason = IDLE_TRANSACTION_FINISH_REASONS[1];
         this.end(endTimestamp);
       }
@@ -335,8 +361,10 @@ export class IdleTransaction extends Transaction {
     if (Object.keys(this.activities).length === 0) {
       const endTimestamp = timestampInSeconds();
       if (this._idleTimeoutCanceledPermanently) {
-        this._finishReason = IDLE_TRANSACTION_FINISH_REASONS[5];
-        this.end(endTimestamp);
+        if (this._autoFinishAllowed) {
+          this._finishReason = IDLE_TRANSACTION_FINISH_REASONS[5];
+          this.end(endTimestamp);
+        }
       } else {
         // We need to add the timeout here to have the real endtimestamp of the transaction
         // Remember timestampInSeconds is in seconds, timeout is in ms
@@ -366,10 +394,12 @@ export class IdleTransaction extends Transaction {
     this._prevHeartbeatString = heartbeatString;
 
     if (this._heartbeatCounter >= 3) {
-      DEBUG_BUILD && logger.log('[Tracing] Transaction finished because of no change for 3 heart beats');
-      this.setStatus('deadline_exceeded');
-      this._finishReason = IDLE_TRANSACTION_FINISH_REASONS[0];
-      this.end();
+      if (this._autoFinishAllowed) {
+        DEBUG_BUILD && logger.log('[Tracing] Transaction finished because of no change for 3 heart beats');
+        this.setStatus('deadline_exceeded');
+        this._finishReason = IDLE_TRANSACTION_FINISH_REASONS[0];
+        this.end();
+      }
     } else {
       this._pingHeartbeat();
     }

packages/tracing-internal/src/browser/browsertracing.ts

@@ -368,8 +368,21 @@ export class BrowserTracing implements Integration {
       true,
       { location }, // for use in the tracesSampler
       heartbeatInterval,
+      isPageloadTransaction, // should wait for finish signal if it is a pageload transaction
     );
 
+    if (isPageloadTransaction) {
+      WINDOW.document.addEventListener('readystatechange', () => {
+        if (WINDOW.document.readyState === 'interactive') {
+          idleTransaction.sendFinishSignal();
+        }
+      });
+
+      if (WINDOW.document.readyState === 'interactive') {
+        idleTransaction.sendFinishSignal();
+      }
+    }
+
     // eslint-disable-next-line deprecation/deprecation
     const scope = hub.getScope();