check that we actually have some information back from redis before assuming its an array with 2 keys to avoid undefined array key warnings as per#45270

so the code in question is this:

publicfunction get(): ?array    {if ($this->autoSetup) {$this->setup();        }$now =microtime();$now =substr($now,11).substr($now,2,3);$queuedMessageCount =$this->rawCommand('ZCOUNT',0,$now);while ($queuedMessageCount--) {if (![$queuedMessage,$expiry] =$this->rawCommand('ZPOPMIN',1)) {break;            }if (\strlen($expiry) ===\strlen($now) ?$expiry >$now :\strlen($expiry) <\strlen($now)) {// if a future-placed message is popped because of a race condition with// another running consumer, the message is readded to the queueif (!$this->rawCommand('ZADD','NX',$expiry,$queuedMessage)) {thrownewTransportException('Could not add a message to the redis stream.');                }break;            }$decodedQueuedMessage =json_decode($queuedMessage,true);$this->add(\array_key_exists('body',$decodedQueuedMessage) ?$decodedQueuedMessage['body'] :$queuedMessage,$decodedQueuedMessage['headers'] ?? [],0);        }

I think what's happening, as I often can have up to 1000 workers (yup, for real, making 1000 http requests to remote sites - see mySites.guru) I think the logic might be flawed.

Because, the following line gets the number of messages using ZCOUNT

$queuedMessageCount =$this->rawCommand('ZCOUNT',0,$now);

It will then enter a loop counting down that number of messages checking them

while ($queuedMessageCount--) {

At the same time, 999 other workers can be doing the same thing

it gets to a point where one of the workers doesnt get a message back fromZPOPMIN and thus we get undefined array keys...

You can see the result of ZPOPMIN is no longer an array once empty using the interactive test on the official redis page.

carsonbot added Status: Needs Review Bug labels

Mar 2, 2022

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carsonbot commentedMar 2, 2022

Hey!

Oh no, it looks like you have made this PR towards a branch that is not maintained anymore. :/
Could you update thePR base branch to target one of these branches instead? 4.4, 5.4, 6.0, 6.1.

Cheers!

Carsonbot