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Blocking queues

Respire supports Redis blocking commands without letting one long wait stall unrelated requests.

Why dedicated connections matter​

A multiplexed connection serves many callers. If BLPOP waited on that socket, commands queued behind it could not receive replies. Respire rents a separate connection for the blocking operation while regular traffic stays on the shared multiplexer.

No second client or manual connection is required.

Wait for work​

while (!stoppingToken.IsCancellationRequested)
{
    string? job = await redis.Lists.LeftPopAsync(
        "jobs",
        waitFor: TimeSpan.FromSeconds(30),
        cancellationToken: stoppingToken);

    if (job is not null)
    {
        await ProcessAsync(job, stoppingToken);
    }
}

waitFor: null performs non-blocking LPOP. Supplying a duration performs BLPOP on a dedicated pooled connection.

Reliable queue movement​

Move a job atomically from a pending queue into a processing queue:

string? job = await redis.Lists.MoveAsync(
    source: "jobs:pending",
    destination: "jobs:processing",
    from: ListSide.Right,
    to: ListSide.Left,
    waitFor: TimeSpan.FromSeconds(30),
    cancellationToken: stoppingToken);

After successful processing, remove the item from jobs:processing. Recovery code can requeue abandoned items.

Cancellation semantics​

Cancellation stops your wait. If a blocking command has already reached the server, Respire safely retires or cleans up the dedicated connection rather than leaving a partial protocol exchange in the shared pool.

Use bounded wait durations when workers also need periodic housekeeping or health updates.