From dead4b4ab6f0aea37bed5cdb0b9a3b3dcd94698d Mon Sep 17 00:00:00 2001
From: Chris Brody <chris.brody+brodybits@gmail.com>
Date: Tue, 9 Jun 2020 19:48:33 -0400
Subject: [PATCH] breaking: reduce combined response cutoff to 16 MB (#987)

* breaking: reduce combined response cutoff to 16 MB
* rename `MAX_PAYLOAD_SIZE` to `COMBINED_RESPONSE_CUTOFF`
* update some comments
* cleanup: split `if` statements into multiple lines
---
 .../cordova/NativeToJsMessageQueue.java       | 24 +++++++++++++------
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/framework/src/org/apache/cordova/NativeToJsMessageQueue.java b/framework/src/org/apache/cordova/NativeToJsMessageQueue.java
index d17b1c43..311ba444 100755
--- a/framework/src/org/apache/cordova/NativeToJsMessageQueue.java
+++ b/framework/src/org/apache/cordova/NativeToJsMessageQueue.java
@@ -36,10 +36,11 @@ public class NativeToJsMessageQueue {
     // exec() is asynchronous. Set this to true when running bridge benchmarks.
     static final boolean DISABLE_EXEC_CHAINING = false;
 
-    // Arbitrarily chosen upper limit for how much data to send to JS in one shot.
-    // This currently only chops up on message boundaries. It may be useful
-    // to allow it to break up messages.
-    private static int MAX_PAYLOAD_SIZE = 50 * 1024 * 10240;
+    // A hopefully reasonable upper limit of how much combined payload data
+    // to send to the JavaScript in one shot.
+    // This currently only chops up on message boundaries.
+    // It may be useful to split and reassemble response messages someday.
+    private static int COMBINED_RESPONSE_CUTOFF = 16 * 1024 * 1024;
 
     /**
      * When true, the active listener is not fired upon enqueue. When set to false,
@@ -124,7 +125,10 @@ public class NativeToJsMessageQueue {
 
     /**
      * Combines and returns queued messages combined into a single string.
-     * Combines as many messages as possible, while staying under MAX_PAYLOAD_SIZE.
+     *
+     * Combines as many messages as possible, without exceeding
+     * COMBINED_RESPONSE_CUTOFF in case of multiple response messages.
+     *
      * Returns null if the queue is empty.
      */
     public String popAndEncode(boolean fromOnlineEvent) {
@@ -140,7 +144,10 @@ public class NativeToJsMessageQueue {
             int numMessagesToSend = 0;
             for (JsMessage message : queue) {
                 int messageSize = calculatePackedMessageLength(message);
-                if (numMessagesToSend > 0 && totalPayloadLen + messageSize > MAX_PAYLOAD_SIZE && MAX_PAYLOAD_SIZE > 0) {
+                if (numMessagesToSend > 0 &&
+                    COMBINED_RESPONSE_CUTOFF > 0 &&
+                    totalPayloadLen + messageSize > COMBINED_RESPONSE_CUTOFF
+                   ) {
                     break;
                 }
                 totalPayloadLen += messageSize;
@@ -175,7 +182,10 @@ public class NativeToJsMessageQueue {
             int numMessagesToSend = 0;
             for (JsMessage message : queue) {
                 int messageSize = message.calculateEncodedLength() + 50; // overestimate.
-                if (numMessagesToSend > 0 && totalPayloadLen + messageSize > MAX_PAYLOAD_SIZE && MAX_PAYLOAD_SIZE > 0) {
+                if (numMessagesToSend > 0 &&
+                    COMBINED_RESPONSE_CUTOFF > 0 &&
+                    totalPayloadLen + messageSize > COMBINED_RESPONSE_CUTOFF
+                   ) {
                     break;
                 }
                 totalPayloadLen += messageSize;