fix: handle RedisException gracefully when retrieving cached data (#1934

)

backend/api/src/main/kotlin/io/tolgee/component/TolgeeCacheErrorHandler.kt

@@ -0,0 +1,46 @@
+/**
+ * Copyright (C) 2023 Tolgee s.r.o. and contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.tolgee.component
+
+import org.redisson.client.RedisException
+import org.slf4j.LoggerFactory
+import org.springframework.cache.Cache
+import org.springframework.cache.interceptor.SimpleCacheErrorHandler
+import java.lang.RuntimeException
+
+class TolgeeCacheErrorHandler : SimpleCacheErrorHandler() {
+  private val logger = LoggerFactory.getLogger(TolgeeCacheErrorHandler::class.java)
+
+  override fun handleCacheGetError(exception: RuntimeException, cache: Cache, key: Any) {
+    if (exception is RedisException) {
+      logger.warn(
+        "Suppressing RedisException for cache {} on key {}. " +
+          "This is likely due to outdated cache data, therefore this cache entry has been removed. " +
+          "If this re-occurs for the same cache and key, it is likely from a bug that should be reported.",
+        cache.name,
+        key,
+      )
+
+      logger.warn("The following error occurred while fetching the key", exception)
+
+      cache.evictIfPresent(key)
+      return
+    }
+
+    throw exception
+  }
+}

backend/api/src/main/kotlin/io/tolgee/configuration/CacheConfiguration.kt

@@ -0,0 +1,29 @@
+/**
+ * Copyright (C) 2023 Tolgee s.r.o. and contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.tolgee.configuration
+
+import io.tolgee.component.TolgeeCacheErrorHandler
+import org.springframework.cache.annotation.CachingConfigurerSupport
+import org.springframework.cache.interceptor.CacheErrorHandler
+import org.springframework.context.annotation.Configuration
+
+@Configuration
+class CacheConfiguration : CachingConfigurerSupport() {
+  override fun errorHandler(): CacheErrorHandler {
+    return TolgeeCacheErrorHandler()
+  }
+}