From dbee06e6f0877ed5030d2ba208753f7955877916 Mon Sep 17 00:00:00 2001
From: Gaofei Zhao <15748980+dippindots@users.noreply.github.com>
Date: Tue, 1 Aug 2023 09:35:48 -0400
Subject: [PATCH] Allow redis service unavailable when Redis is enabled

---
 .../persistence/config/RedisConfig.java       |  8 ++++
 .../util/LoggingCacheErrorHandler.java        | 43 +++++++++++++++++++
 2 files changed, 51 insertions(+)
 create mode 100644 persistence/persistence-api/src/main/java/org/cbioportal/persistence/util/LoggingCacheErrorHandler.java

diff --git a/persistence/persistence-api/src/main/java/org/cbioportal/persistence/config/RedisConfig.java b/persistence/persistence-api/src/main/java/org/cbioportal/persistence/config/RedisConfig.java
index 9aad4491870..2da81e8787c 100644
--- a/persistence/persistence-api/src/main/java/org/cbioportal/persistence/config/RedisConfig.java
+++ b/persistence/persistence-api/src/main/java/org/cbioportal/persistence/config/RedisConfig.java
@@ -2,14 +2,17 @@
 
 import org.cbioportal.persistence.util.CustomKeyGenerator;
 import org.cbioportal.persistence.util.CustomRedisCachingProvider;
+import org.cbioportal.persistence.util.LoggingCacheErrorHandler;
 import org.cbioportal.utils.config.annotation.ConditionalOnProperty;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.cache.CacheManager;
 import org.springframework.cache.annotation.CachingConfigurerSupport;
 import org.springframework.cache.annotation.EnableCaching;
+import org.springframework.cache.interceptor.CacheErrorHandler;
 import org.springframework.cache.interceptor.CacheResolver;
 import org.springframework.cache.interceptor.KeyGenerator;
 import org.springframework.cache.interceptor.NamedCacheResolver;
+
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 
@@ -29,6 +32,11 @@ public CacheManager cacheManager() {
         );
     }
 
+    @Override
+    public CacheErrorHandler errorHandler() {
+        return new LoggingCacheErrorHandler();
+    }
+
     @Bean
     @Override
     public KeyGenerator keyGenerator() {
diff --git a/persistence/persistence-api/src/main/java/org/cbioportal/persistence/util/LoggingCacheErrorHandler.java b/persistence/persistence-api/src/main/java/org/cbioportal/persistence/util/LoggingCacheErrorHandler.java
new file mode 100644
index 00000000000..a682c568dca
--- /dev/null
+++ b/persistence/persistence-api/src/main/java/org/cbioportal/persistence/util/LoggingCacheErrorHandler.java
@@ -0,0 +1,43 @@
+package org.cbioportal.persistence.util;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.cache.Cache;
+import org.springframework.cache.interceptor.CacheErrorHandler;
+
+/**
+ * Implementation of org.springframework.cache.interceptor.CacheErrorHandler
+ * that logs the error messages when performing Redis operations.
+ * Redis will throw a RuntimeException causing our APIs to return HTTP 500 responses, so we defined
+ * this class to just log the errors and allow our app fallback to the non-cached version.
+ */
+
+public class LoggingCacheErrorHandler implements CacheErrorHandler {
+
+    private static final Logger LOG = LoggerFactory.getLogger(LoggingCacheErrorHandler.class);
+
+    @Override
+    public void handleCacheGetError(RuntimeException exception, Cache cache, Object key) {
+        LOG.error(String.format("Cache '%s' failed to get entry with key '%s'", cache.getName(), key), exception);
+        LOG.error(String.format("Cache error message: '%s'", exception.getMessage()));
+    }
+
+    @Override
+    public void handleCachePutError(RuntimeException exception, Cache cache, Object key, Object value) {
+        LOG.error(String.format("Cache '%s' failed to put entry with key '%s'", cache.getName(), key), exception);
+        LOG.error(String.format("Cache error message: '%s'", exception.getMessage()));
+    }
+
+    @Override
+    public void handleCacheEvictError(RuntimeException exception, Cache cache, Object key) {
+        LOG.error(String.format("Cache '%s' failed to evict entry with key '%s'", cache.getName(), key), exception);
+        LOG.error(String.format("Cache error message: '%s'", exception.getMessage()));
+    }
+
+    @Override
+    public void handleCacheClearError(RuntimeException exception, Cache cache) {
+        LOG.error(String.format("Cache '%s' failed to clear entries", cache.getName()), exception);
+        LOG.error(String.format("Cache error message: '%s'", exception.getMessage()));
+    }
+
+}