From 51b701eefeb2b34a5a85e470d4bf8f885ebfd1e1 Mon Sep 17 00:00:00 2001
From: Mikhail Bezoyan <mbezoyan@twitter.com>
Date: Tue, 16 Jan 2024 22:38:50 +0000
Subject: [PATCH] [finagle-core] Fix for DeadlineFilter takes rejectWithdrawal
 regardless of passed Deadline

Problem
DeadlineFilter takes rejectWithdrawal regardless of passed Deadline
https://github.com/twitter/finagle/issues/936

Solution
Withdraw tokens only if the deadline has passed

Closes twitter/finagle#936

Differential Revision: https://phabricator.twitter.biz/D1120240
---
 CHANGELOG.rst                                               | 5 +++++
 .../scala/com/twitter/finagle/service/DeadlineFilter.scala  | 6 +++---
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 639cab0f5b..02a3baa97f 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -7,6 +7,11 @@ Note that ``PHAB_ID=#`` and ``RB_ID=#`` correspond to associated messages in com
 Unreleased
 ----------
 
+Bug Fixes
+~~~~~~~~~~
+
+* finagle-core: Fix for DeadlineFilter takes rejectWithdrawal regardless of passed Deadline. ``PHAB_ID=D1120240``
+
 23.11.0
 -------
 
diff --git a/finagle-core/src/main/scala/com/twitter/finagle/service/DeadlineFilter.scala b/finagle-core/src/main/scala/com/twitter/finagle/service/DeadlineFilter.scala
index f2946520fa..b2b0deb958 100644
--- a/finagle-core/src/main/scala/com/twitter/finagle/service/DeadlineFilter.scala
+++ b/finagle-core/src/main/scala/com/twitter/finagle/service/DeadlineFilter.scala
@@ -280,9 +280,6 @@ class DeadlineFilter[Req, Rep](
 
         val now = Time.now
         val difference: Duration = deadline - now
-        val reject = rejectBucket.tryGet(rejectWithdrawal)
-
-        trace(tracing, deadline, difference, reject)
 
         // If the difference is negative, we've exceeded the deadline
         if (difference.inMillis < 0l) {
@@ -291,6 +288,8 @@ class DeadlineFilter[Req, Rep](
           expiredTimeStat.add(exceeded.inMillis)
 
           // There are enough tokens to reject the request
+          val reject = rejectBucket.tryGet(rejectWithdrawal)
+          trace(tracing, deadline, difference, reject)
           if (reject) {
             rejectedCounter.incr()
             if (isDarkMode)
@@ -304,6 +303,7 @@ class DeadlineFilter[Req, Rep](
             service(request)
           }
         } else {
+          trace(tracing, deadline, difference, false)
           rejectBucket.put(serviceDeposit)
           val remaining = difference
           remainingTimeStat.add(remaining.inMillis)