I have an application that saves data in redis, this data arrives through events in a queue which generates a high concurrency environment. To maintain data consistency I have used the Redis MULTI / EXEC statement and in case of failure the data is not confirmed. Before opening MULTI I need to query Redis for data.
I present an example case.
Test endpoint with which I simulate the events:
@GET@Path("/foo")public Response foo() { String queue = "foo"; for (int i = 0; i < 10000; i++) { activeMqClient.addToQueue(queue, new Foo(i, "Message " + 1)); } return OkResponse.toResponse("Foo send OK");}Event burning (running multiple instances in threads):
public class FooRedisCmd { public void process(Foo foo) { // Example RedisClient redisClient = null; Response multiResponse = null; try { redisClient = RedisClient.createClient(); //get info redisClient.hget("foos", "foo_field1:" + foo.getId()); redisClient.hget("foos", "foo_field2:" + foo.getId()); redisClient.hget("foos", "foo_field3:" + foo.getId()); redisClient.hget("foos", "foo_field4:" + foo.getId()); redisClient.hget("foos", "foo_field5:" + foo.getId()); redisClient.hget("foos", "foo_field6:" + foo.getId()); redisClient.hget("foos", "foo_field7:" + foo.getId()); //write info multiResponse = redisClient.multi(); log.info("Get multi: {} for foo: {}", multiResponse, foo); redisClient.hincrby("foos", "foo_field1:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field2:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field3:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field4:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field5:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field6:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field7:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field8:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field9:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field10:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field11:" + foo.getId(), Integer.toString(1)); redisClient.hincrby("foos", "foo_field12:" + foo.getId(), Integer.toString(1)); Response execResponse = redisClient.exec(); log.info("Multi result: {} for foo: {}", execResponse, foo); } catch (Exception e) { if (multiResponse != null) { try { redisClient.discard(); } catch (Exception e2) { log.error("Error on discard for foo: {}", foo, e2); } } log.error("Error on exec for foo: {}", foo, e); } finally { if (redisClient != null) { redisClient.close(); } } }}Errors:
INFO [com.foo.FooRedisCmd] (pool-17-thread-3) Get multi: OK for foo: Foo(id=9965, message=Message 1)INFO [com.foo.FooRedisCmd] (pool-17-thread-3) Multi result: [3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3] for foo: Foo(id=9965, message=Message 1)INFO [com.foo.FooRedisCmd] (pool-17-thread-1) Get multi: OK for foo: Foo(id=9966, message=Message 1)ERROR [com.foo.FooRedisCmd] (pool-17-thread-1) Error on discard for foo: Foo(id=9966, message=Message 1): java.util.concurrent.CompletionException: ERR DISCARD without MULTI at io.smallrye.mutiny.operators.uni.UniBlockingAwait.await(UniBlockingAwait.java:73) at io.smallrye.mutiny.groups.UniAwait.atMost(UniAwait.java:61) at io.quarkus.redis.client.runtime.RedisClientImpl.await(RedisClientImpl.java:1026) at io.quarkus.redis.client.runtime.RedisClientImpl.discard(RedisClientImpl.java:142) at com.foo.FooRedisCmd.process(FooRedisCmd.java:48) at com.foo.FooRedisCmd_Subclass.process$$superforward1(FooRedisCmd_Subclass.zig:94) at com.foo.FooRedisCmd_Subclass$$function$$1.apply(FooRedisCmd_Subclass$$function$$1.zig:33) at io.quarkus.arc.impl.AroundInvokeInvocationContext.proceed(AroundInvokeInvocationContext.java:54) at io.quarkus.arc.runtime.devconsole.InvocationInterceptor.proceed(InvocationInterceptor.java:62) at io.quarkus.arc.runtime.devconsole.InvocationInterceptor.monitor(InvocationInterceptor.java:51) at io.quarkus.arc.runtime.devconsole.InvocationInterceptor_Bean.intercept(InvocationInterceptor_Bean.zig:521) at io.quarkus.arc.impl.InterceptorInvocation.invoke(InterceptorInvocation.java:41) at io.quarkus.arc.impl.AroundInvokeInvocationContext.perform(AroundInvokeInvocationContext.java:41) at io.quarkus.arc.impl.InvocationContexts.performAroundInvoke(InvocationContexts.java:32) at com.foo.FooRedisCmd_Subclass.process(FooRedisCmd_Subclass.zig:158) at com.foo.FooRedisCmd_ClientProxy.process(FooRedisCmd_ClientProxy.zig:128) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) at java.base/java.lang.Thread.run(Thread.java:829)Caused by: ERR DISCARD without MULTIINFO [com.foo.FooRedisCmd] (pool-17-thread-2) Get multi: OK for foo: Foo(id=9967, message=Message 1)ERROR [com.foo.FooRedisCmd] (pool-17-thread-1) Error on exec for foo: Foo(id=9966, message=Message 1): java.util.concurrent.CompletionException: ERR EXEC without MULTI at io.smallrye.mutiny.operators.uni.UniBlockingAwait.await(UniBlockingAwait.java:73) at io.smallrye.mutiny.groups.UniAwait.atMost(UniAwait.java:61) at io.quarkus.redis.client.runtime.RedisClientImpl.await(RedisClientImpl.java:1026) at io.quarkus.redis.client.runtime.RedisClientImpl.exec(RedisClientImpl.java:167) at com.foo.FooRedisCmd.process(FooRedisCmd.java:43) at com.foo.FooRedisCmd_Subclass.process$$superforward1(FooRedisCmd_Subclass.zig:94) at com.foo.FooRedisCmd_Subclass$$function$$1.apply(FooRedisCmd_Subclass$$function$$1.zig:33) at io.quarkus.arc.impl.AroundInvokeInvocationContext.proceed(AroundInvokeInvocationContext.java:54) at io.quarkus.arc.runtime.devconsole.InvocationInterceptor.proceed(InvocationInterceptor.java:62) at io.quarkus.arc.runtime.devconsole.InvocationInterceptor.monitor(InvocationInterceptor.java:51) at io.quarkus.arc.runtime.devconsole.InvocationInterceptor_Bean.intercept(InvocationInterceptor_Bean.zig:521) at io.quarkus.arc.impl.InterceptorInvocation.invoke(InterceptorInvocation.java:41) at io.quarkus.arc.impl.AroundInvokeInvocationContext.perform(AroundInvokeInvocationContext.java:41) at io.quarkus.arc.impl.InvocationContexts.performAroundInvoke(InvocationContexts.java:32) at com.foo.FooRedisCmd_Subclass.process(FooRedisCmd_Subclass.zig:158) at com.foo.FooRedisCmd_ClientProxy.process(FooRedisCmd_ClientProxy.zig:128) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) at java.base/java.lang.Thread.run(Thread.java:829)Caused by: ERR EXEC without MULTIINFO [com.foo.FooRedisCmd] (pool-17-thread-2) Multi result: [3, 3, 3, 3, 3, 3, 3, 3, 3, 3] for foo: Foo(id=9967, message=Message 1)Errors are generated when executing both the exec and the discard when the first one fails. Why is this happening? I am using quarkus 2 and its own client for redis quarkus-redis-client.