From 0871d6ebc113761741ff19fea2c1198af25832e3 Mon Sep 17 00:00:00 2001
From: Jon Chambers <jon@signal.org>
Date: Fri, 7 Jun 2024 19:11:55 -0400
Subject: [PATCH] Add a log filter for spurious warnings about unsupported
 channel options

---
 .../logging/UnknownKeepaliveOptionFilter.java | 26 +++++++++++++++++++
 .../UnknownKeepaliveOptionFilterFactory.java  | 15 +++++++++++
 ...wizard.logging.common.filter.FilterFactory |  1 +
 service/src/test/resources/logback-test.xml   |  4 +++
 4 files changed, 46 insertions(+)
 create mode 100644 service/src/main/java/org/whispersystems/textsecuregcm/util/logging/UnknownKeepaliveOptionFilter.java
 create mode 100644 service/src/main/java/org/whispersystems/textsecuregcm/util/logging/UnknownKeepaliveOptionFilterFactory.java

diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/util/logging/UnknownKeepaliveOptionFilter.java b/service/src/main/java/org/whispersystems/textsecuregcm/util/logging/UnknownKeepaliveOptionFilter.java
new file mode 100644
index 000000000..b2570f797
--- /dev/null
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/util/logging/UnknownKeepaliveOptionFilter.java
@@ -0,0 +1,26 @@
+package org.whispersystems.textsecuregcm.util.logging;
+
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.filter.Filter;
+import ch.qos.logback.core.spi.FilterReply;
+
+/**
+ * Filters spurious warnings about setting a very specific channel option on local channels.
+ * <p/>
+ * gRPC unconditionally tries to set the {@code SO_KEEPALIVE} option on all of its channels, but local channels, which
+ * are used by the Noise-over-WebSocket tunnel, do not support {@code SO_KEEPALIVE} and log a warning on each new
+ * channel. We don't want to filter <em>all</em> warnings from the relevant logger, and so this custom filter denies
+ * attempts to log the specific spurious message.
+ */
+public class UnknownKeepaliveOptionFilter extends Filter<ILoggingEvent> {
+
+  private static final String MESSAGE_PREFIX = "Unknown channel option 'SO_KEEPALIVE'";
+
+  @Override
+  public FilterReply decide(final ILoggingEvent event) {
+    final boolean loggerNameMatches = "io.netty.bootstrap.Bootstrap".equals(event.getLoggerName()) ||
+        "io.netty.bootstrap.ServerBootstrap".equals(event.getLoggerName());
+
+    return loggerNameMatches && event.getMessage().startsWith(MESSAGE_PREFIX) ? FilterReply.DENY : FilterReply.NEUTRAL;
+  }
+}
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/util/logging/UnknownKeepaliveOptionFilterFactory.java b/service/src/main/java/org/whispersystems/textsecuregcm/util/logging/UnknownKeepaliveOptionFilterFactory.java
new file mode 100644
index 000000000..31d09bb06
--- /dev/null
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/util/logging/UnknownKeepaliveOptionFilterFactory.java
@@ -0,0 +1,15 @@
+package org.whispersystems.textsecuregcm.util.logging;
+
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.filter.Filter;
+import com.fasterxml.jackson.annotation.JsonTypeName;
+import io.dropwizard.logging.common.filter.FilterFactory;
+
+@JsonTypeName("unknownKeepaliveOption")
+public class UnknownKeepaliveOptionFilterFactory implements FilterFactory<ILoggingEvent> {
+
+  @Override
+  public Filter<ILoggingEvent> build() {
+    return new UnknownKeepaliveOptionFilter();
+  }
+}
diff --git a/service/src/main/resources/META-INF/services/io.dropwizard.logging.common.filter.FilterFactory b/service/src/main/resources/META-INF/services/io.dropwizard.logging.common.filter.FilterFactory
index 5e33b192a..1de0bbae5 100644
--- a/service/src/main/resources/META-INF/services/io.dropwizard.logging.common.filter.FilterFactory
+++ b/service/src/main/resources/META-INF/services/io.dropwizard.logging.common.filter.FilterFactory
@@ -1 +1,2 @@
 org.whispersystems.textsecuregcm.util.logging.RequestLogEnabledFilterFactory
+org.whispersystems.textsecuregcm.util.logging.UnknownKeepaliveOptionFilterFactory
diff --git a/service/src/test/resources/logback-test.xml b/service/src/test/resources/logback-test.xml
index b01f95f92..f149694a8 100644
--- a/service/src/test/resources/logback-test.xml
+++ b/service/src/test/resources/logback-test.xml
@@ -1,5 +1,9 @@
 <configuration>
+  <import class="org.whispersystems.textsecuregcm.util.logging.UnknownKeepaliveOptionFilter"/>
+
   <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+    <filter class="UnknownKeepaliveOptionFilter"/>
+
     <encoder>
       <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
     </encoder>