From d82d91a8febd0c138b7fa476315459f12fb37e7e Mon Sep 17 00:00:00 2001
From: Bastien Caudan <bastien.caudan@datadoghq.com>
Date: Mon, 19 Apr 2021 11:36:54 +0200
Subject: [PATCH] =?UTF-8?q?=F0=9F=90=9B=20fallback=20to=20xhr=20when=20sen?=
 =?UTF-8?q?dBeacon=20throws=20(#796)?=
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Content-Type: text/plain; charset=UTF-8
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* 🐛 fallback to xhr when sendBeacon throws

* 🐛 avoid a loop of reporting errors if beacon systematically throws
---
 packages/core/src/transport/transport.spec.ts | 11 ++++++++++
 packages/core/src/transport/transport.ts      | 20 +++++++++++++++----
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/packages/core/src/transport/transport.spec.ts b/packages/core/src/transport/transport.spec.ts
index 1865fe91e3..bd06d80213 100644
--- a/packages/core/src/transport/transport.spec.ts
+++ b/packages/core/src/transport/transport.spec.ts
@@ -53,6 +53,17 @@ describe('request', () => {
     expect(navigator.sendBeacon).toHaveBeenCalled()
     expect(server.requests.length).toEqual(1)
   })
+
+  it('should fallback to xhr when sendBeacon throws', () => {
+    spyOn(navigator, 'sendBeacon').and.callFake(() => {
+      throw new TypeError()
+    })
+
+    request.send('{"foo":"bar1"}\n{"foo":"bar2"}', 10)
+
+    expect(navigator.sendBeacon).toHaveBeenCalled()
+    expect(server.requests.length).toEqual(1)
+  })
 })
 
 describe('batch', () => {
diff --git a/packages/core/src/transport/transport.ts b/packages/core/src/transport/transport.ts
index a059015b78..dfb251c381 100644
--- a/packages/core/src/transport/transport.ts
+++ b/packages/core/src/transport/transport.ts
@@ -1,7 +1,7 @@
 import { Context } from '../tools/context'
 import { getTimeStamp, relativeNow } from '../tools/timeUtils'
 import { addEventListener, DOM_EVENT, jsonStringify, noop, objectValues } from '../tools/utils'
-import { monitor } from '../domain/internalMonitoring'
+import { monitor, addErrorToMonitoringBatch } from '../domain/internalMonitoring'
 
 // https://en.wikipedia.org/wiki/UTF-8
 const HAS_MULTI_BYTES_CHARACTERS = /[^\u0000-\u007F]/
@@ -20,9 +20,13 @@ export class HttpRequest {
   send(data: string | FormData, size: number) {
     const url = this.withBatchTime ? addBatchTime(this.endpointUrl) : this.endpointUrl
     if (navigator.sendBeacon && size < this.bytesLimit) {
-      const isQueued = navigator.sendBeacon(url, data)
-      if (isQueued) {
-        return
+      try {
+        const isQueued = navigator.sendBeacon(url, data)
+        if (isQueued) {
+          return
+        }
+      } catch (e) {
+        reportBeaconError(e)
       }
     }
     const request = new XMLHttpRequest()
@@ -37,6 +41,14 @@ function addBatchTime(url: string) {
   )}`
 }
 
+let hasReportedBeaconError = false
+function reportBeaconError(e: unknown) {
+  if (!hasReportedBeaconError) {
+    hasReportedBeaconError = true
+    addErrorToMonitoringBatch(e)
+  }
+}
+
 export class Batch {
   private pushOnlyBuffer: string[] = []
   private upsertBuffer: { [key: string]: string } = {}