From 1fb98cc276bd5d3723d896cb574dd32eaaab67f6 Mon Sep 17 00:00:00 2001
From: Michael Lehenbauer <mikelehen@google.com>
Date: Thu, 19 Dec 2019 16:06:18 -0800
Subject: [PATCH 1/2] Avoid using $httpHeaders in environments that don't send
 an Origin header.

There is a backend bug (b/145624756) causing $httpHeaders to be ignored if an Origin header is not sent.  Via https://github.com/firebase/firebase-js-sdk/issues/1491 we've found that several environments can run into this issue so until the backend issue is fixed we are excluding them from using $httpHeaders. This may incur an extra CORS preflight round-trip in some cases, but this is much better than having our Authorization header get ignored.
---
 packages/firestore/CHANGELOG.md                  |  4 ++++
 .../platform_browser/webchannel_connection.ts    | 12 ++++++------
 packages/util/src/environment.ts                 | 16 ++++++++++++++++
 3 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/packages/firestore/CHANGELOG.md b/packages/firestore/CHANGELOG.md
index dd419f3929d..2cac668f4b1 100644
--- a/packages/firestore/CHANGELOG.md
+++ b/packages/firestore/CHANGELOG.md
@@ -1,4 +1,8 @@
 # Unreleased
+- [fixed] Fixed an issue where auth credentials were not respected in certain
+  browser environments (Electron 7, IE11 in trusted zone, UWP apps). (#1491)
+
+# 1.9.0
 - [feature] Added support for storing and retrieving custom types in Firestore.
   Added support for strongly typed collections, documents, and
   queries. You can now use `withConverter()` to supply a custom data
diff --git a/packages/firestore/src/platform_browser/webchannel_connection.ts b/packages/firestore/src/platform_browser/webchannel_connection.ts
index 919b433c065..c1b64b61e84 100644
--- a/packages/firestore/src/platform_browser/webchannel_connection.ts
+++ b/packages/firestore/src/platform_browser/webchannel_connection.ts
@@ -25,7 +25,7 @@ import {
   XhrIo
 } from '@firebase/webchannel-wrapper';
 
-import { isReactNative } from '@firebase/util';
+import { isElectron, isIE, isReactNative, isUWP } from '@firebase/util';
 
 import { Token } from '../api/credentials';
 import { DatabaseId, DatabaseInfo } from '../core/database_info';
@@ -264,11 +264,11 @@ export class WebChannelConnection implements Connection {
     // formally defined here:
     // https://github.com/google/closure-library/blob/b0e1815b13fb92a46d7c9b3c30de5d6a396a3245/closure/goog/net/rpc/httpcors.js#L32
     //
-    // But for some unclear reason (see
-    // https://github.com/firebase/firebase-js-sdk/issues/703), this breaks
-    // ReactNative and so we exclude it, which just means ReactNative may be
-    // subject to the extra network roundtrip for CORS preflight.
-    if (!isReactNative()) {
+    // TODO(b/145624756): There is a backend bug where $httpHeaders isn't respected if the request
+    // doesn't have an Origin header. So we have to exclude a few browser environments that are
+    // known to (sometimes) not include an Origin. See
+    // https://github.com/firebase/firebase-js-sdk/issues/1491.
+    if (!isReactNative() && !isElectron() && !isIE() && !isUWP()) {
       request.httpHeadersOverwriteParam = '$httpHeaders';
     }
 
diff --git a/packages/util/src/environment.ts b/packages/util/src/environment.ts
index 512a3368f05..75f31e8d588 100644
--- a/packages/util/src/environment.ts
+++ b/packages/util/src/environment.ts
@@ -83,6 +83,22 @@ export function isReactNative(): boolean {
   );
 }
 
+/** Detects Electron apps. */
+export function isElectron(): boolean {
+  return getUA().indexOf('electron/') >= 0;
+}
+
+/** Detects Internet Explorer. */
+export function isIE(): boolean {
+  const ua = getUA();
+  return ua.indexOf('MSIE ') >= 0 || ua.indexOf('Trident/') >= 0;
+}
+
+/** Detects Universal Windows Platform apps. */
+export function isUWP(): boolean {
+  return getUA().indexOf('MSAppHost/') >= 0;
+}
+
 /**
  * Detect whether the current SDK build is the Node version.
  *

From e16fb4a10e73aa15addd314f0ebffa9c12c84c1e Mon Sep 17 00:00:00 2001
From: Michael Lehenbauer <mikelehen@google.com>
Date: Thu, 19 Dec 2019 16:24:44 -0800
Subject: [PATCH 2/2] Fix Electron/ casing.

---
 packages/util/src/environment.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/util/src/environment.ts b/packages/util/src/environment.ts
index 75f31e8d588..cb4bd4c9b91 100644
--- a/packages/util/src/environment.ts
+++ b/packages/util/src/environment.ts
@@ -85,7 +85,7 @@ export function isReactNative(): boolean {
 
 /** Detects Electron apps. */
 export function isElectron(): boolean {
-  return getUA().indexOf('electron/') >= 0;
+  return getUA().indexOf('Electron/') >= 0;
 }
 
 /** Detects Internet Explorer. */