> ## Documentation Index
> Fetch the complete documentation index at: https://upstash.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# LMPOP

> Pop from the first non-empty list.

Use `LMPOP` to pop elements from the first of several lists that is not empty.

`<numkeys>` states how many keys follow, `LEFT` or `RIGHT` chooses the end to pop from, and `COUNT` sets how many elements to take, defaulting to one. Keys are examined in the order given and only the first non-empty one is touched, which is exactly what a priority queue needs: list the high priority queue first and it is drained before the others are looked at.

The reply names the key that was popped from together with the elements, so a caller working with several queues knows where the work came from. When every key is empty the reply is null; use [`BLMPOP`](/docs/redis/commands/list/blmpop) to wait instead.

## Syntax

```redis theme={"system"}
LMPOP <numkeys> <key> [<key> ...] (LEFT | RIGHT) [COUNT <count>]
```

## Arguments

| Argument          | Required | Repeatable | Description                                             |
| ----------------- | -------- | ---------- | ------------------------------------------------------- |
| `<numkeys>`       | Yes      | No         | Number of key arguments that follow.                    |
| `<key>`           | Yes      | Yes        | Redis key targeted by the command.                      |
| `(LEFT \| RIGHT)` | Yes      | No         | Which end to pop from: `LEFT` (head) or `RIGHT` (tail). |
| `COUNT <count>`   | No       | No         | Maximum number of elements to pop.                      |

## Response

The reply reports the result of the operation. Error replies have the same shape in RESP2 and RESP3 and are surfaced as exceptions by the SDKs below.

| Protocol | Reply                                                                         |
| -------- | ----------------------------------------------------------------------------- |
| RESP2    | Null bulk string or null array, or two-element array: key and array of values |
| RESP3    | Null, or two-element array: key and array of values                           |

<Note>
  Client libraries often decode bulk strings, maps, sets, and numeric strings into language-native values. The table describes the Redis wire reply.
</Note>

## Examples

TCP examples use the TLS `REDIS_URL` from the Upstash console. REST examples use `UPSTASH_REDIS_REST_URL` and `UPSTASH_REDIS_REST_TOKEN`.

<AccordionGroup>
  <Accordion title="Redis CLI" icon="terminal">
    ```bash theme={"system"}
    LMPOP 1 my-key LEFT
    ```
  </Accordion>

  <Accordion title="@upstash/redis" icon="node-js" iconType="brands">
    ```ts theme={"system"}
    import { Redis } from "@upstash/redis";

    const redis = Redis.fromEnv();
    const result = await redis.lmpop(1, ["my-key"], "LEFT");
    console.log(result);
    ```
  </Accordion>

  <Accordion title="upstash_redis" icon="python" iconType="brands">
    <Note>
      This command is not supported yet in `upstash_redis`.
    </Note>
  </Accordion>

  <Accordion title="ioredis" icon="node-js" iconType="brands">
    ```ts theme={"system"}
    import Redis from "ioredis";

    const redis = new Redis(process.env.REDIS_URL!);
    const result = await redis.lmpop("1", "my-key", "LEFT");
    console.log(result);
    ```
  </Accordion>

  <Accordion title="node-redis" icon="node-js" iconType="brands">
    ```ts theme={"system"}
    import { createClient } from "redis";

    const client = await createClient({ url: process.env.REDIS_URL })
      .on("error", console.error)
      .connect();
    const result = await client.lmPop("my-key", "LEFT");
    console.log(result);
    ```
  </Accordion>

  <Accordion title="redis-py" icon="python" iconType="brands">
    ```python theme={"system"}
    import os
    import redis

    client = redis.from_url(os.environ["REDIS_URL"])
    result = client.lmpop(1, "my-key", direction="LEFT")
    print(result)
    ```
  </Accordion>

  <Accordion title="go-redis" icon="golang" iconType="brands">
    ```go theme={"system"}
    package main

    import (
        "context"
        "fmt"
        "os"

        "github.com/redis/go-redis/v9"
    )

    func main() {
        opts, err := redis.ParseURL(os.Getenv("REDIS_URL"))
        if err != nil {
            panic(err)
        }
        client := redis.NewClient(opts)
        _, result, err := client.LMPop(context.Background(), "LEFT", 0, "my-key").Result()
        if err != nil {
            panic(err)
        }
        fmt.Println(result)
    }
    ```
  </Accordion>

  <Accordion title="jedis" icon="java" iconType="brands">
    ```java theme={"system"}
    import java.net.URI;

    import redis.clients.jedis.Jedis;

    try (Jedis jedis = new Jedis(new URI(System.getenv("REDIS_URL")))) {
      Object result = jedis.lmpop(redis.clients.jedis.args.ListDirection.LEFT, "my-key");
      System.out.println(result);
    }
    ```
  </Accordion>

  <Accordion title="redis-rs" icon="rust" iconType="brands">
    ```rust theme={"system"}
    use redis::{Direction, TypedCommands};

    fn main() -> redis::RedisResult<()> {
        let url = std::env::var("REDIS_URL").expect("REDIS_URL is not set");
        let client = redis::Client::open(url)?;
        let mut connection = client.get_connection()?;

        let result = connection.lmpop(1, "my-key", Direction::Left, 1)?;
        println!("{result:?}");
        Ok(())
    }
    ```
  </Accordion>
</AccordionGroup>


## Related topics

- [Changelog](/docs/redis/overall/changelog.md)
- [BLMPOP](/docs/redis/commands/list/blmpop.md)