redis-on-mysql 0.0.1

A Redis-compatible proxy that stores all data and Pub/Sub state in MySQL
Documentation
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use bytes::Bytes;
use resp_async::response::RespError;
use resp_async::{Cmd, State, Value};
use sqlx::{MySqlPool, Row};
use std::sync::Arc;

use crate::handlers::util::{
    arg_as_bytes, arg_as_i64, glob_match, random_index, shuffle_slice, wrong_arity, wrong_type,
};
use crate::state::{AppState, SessionHandle, now_ms};
use crate::storage::{TYPE_SET, delete_key_in_tx, load_meta, map_sql_err};

pub async fn sadd(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    if cmd.args.len() < 2 {
        return Err(wrong_arity("SADD"));
    }
    let auth = session.auth().await.ok_or(RespError::NoAuth)?;
    state.pools.touch(&auth.user);
    let key = arg_as_bytes(&cmd.args[0])?;
    let now = now_ms() as i64;
    if let Some(meta) = load_meta(auth.pool.as_ref(), key, now).await?
        && meta.r_type != TYPE_SET
    {
        return Ok(wrong_type());
    }

    let mut members = Vec::with_capacity(cmd.args.len() - 1);
    for arg in cmd.args.iter().skip(1) {
        members.push(arg_as_bytes(arg)?.clone());
    }

    let mut tx = auth.pool.begin().await.map_err(map_sql_err)?;
    let mut qb = sqlx::QueryBuilder::new("INSERT IGNORE INTO redis_set (r_key, member) ");
    qb.push_values(members.iter(), |mut row, member| {
        row.push_bind(key.as_ref());
        row.push_bind(member.as_ref());
    });
    let res = qb.build().execute(&mut *tx).await.map_err(map_sql_err)?;
    let added = res.rows_affected() as i64;
    if added > 0 {
        sqlx::query(
            "INSERT INTO redis_kv (r_key, r_type, r_len, expires_at_ms) \
             VALUES (?, ?, ?, NULL) \
             ON DUPLICATE KEY UPDATE r_len = r_len + VALUES(r_len)",
        )
        .bind(key.as_ref())
        .bind(TYPE_SET)
        .bind(added)
        .execute(&mut *tx)
        .await
        .map_err(map_sql_err)?;
    }
    tx.commit().await.map_err(map_sql_err)?;
    Ok(Value::Integer(added))
}

pub async fn srem(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    if cmd.args.len() < 2 {
        return Err(wrong_arity("SREM"));
    }
    let auth = session.auth().await.ok_or(RespError::NoAuth)?;
    state.pools.touch(&auth.user);
    let key = arg_as_bytes(&cmd.args[0])?;
    let now = now_ms() as i64;
    let meta = load_meta(auth.pool.as_ref(), key, now).await?;
    let Some(meta) = meta else {
        return Ok(Value::Integer(0));
    };
    if meta.r_type != TYPE_SET {
        return Ok(wrong_type());
    }

    let mut qb = sqlx::QueryBuilder::new("DELETE FROM redis_set WHERE r_key = ");
    qb.push_bind(key.as_ref());
    qb.push(" AND member IN (");
    let mut separated = qb.separated(", ");
    for arg in cmd.args.iter().skip(1) {
        let member = arg_as_bytes(arg)?;
        separated.push_bind(member.as_ref());
    }
    qb.push(")");

    let mut tx = auth.pool.begin().await.map_err(map_sql_err)?;
    let res = qb.build().execute(&mut *tx).await.map_err(map_sql_err)?;
    let removed = res.rows_affected() as i64;
    if removed > 0 {
        let res =
            sqlx::query("UPDATE redis_kv SET r_len = r_len - ? WHERE r_key = ? AND r_type = ?")
                .bind(removed)
                .bind(key.as_ref())
                .bind(TYPE_SET)
                .execute(&mut *tx)
                .await
                .map_err(map_sql_err)?;
        if res.rows_affected() > 0 {
            sqlx::query("DELETE FROM redis_kv WHERE r_key = ? AND r_type = ? AND r_len <= 0")
                .bind(key.as_ref())
                .bind(TYPE_SET)
                .execute(&mut *tx)
                .await
                .map_err(map_sql_err)?;
        }
    }
    tx.commit().await.map_err(map_sql_err)?;
    Ok(Value::Integer(removed))
}

pub async fn sismember(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    if cmd.args.len() != 2 {
        return Err(wrong_arity("SISMEMBER"));
    }
    let auth = session.auth().await.ok_or(RespError::NoAuth)?;
    state.pools.touch(&auth.user);
    let key = arg_as_bytes(&cmd.args[0])?;
    let member = arg_as_bytes(&cmd.args[1])?;
    let now = now_ms() as i64;
    let meta = load_meta(auth.pool.as_ref(), key, now).await?;
    let Some(meta) = meta else {
        return Ok(Value::Integer(0));
    };
    if meta.r_type != TYPE_SET {
        return Ok(wrong_type());
    }

    let row = sqlx::query("SELECT 1 FROM redis_set WHERE r_key = ? AND member = ?")
        .bind(key.as_ref())
        .bind(member.as_ref())
        .fetch_optional(auth.pool.as_ref())
        .await
        .map_err(map_sql_err)?;
    Ok(Value::Integer(if row.is_some() { 1 } else { 0 }))
}

pub async fn smembers(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    if cmd.args.len() != 1 {
        return Err(wrong_arity("SMEMBERS"));
    }
    let auth = session.auth().await.ok_or(RespError::NoAuth)?;
    state.pools.touch(&auth.user);
    let key = arg_as_bytes(&cmd.args[0])?;
    let now = now_ms() as i64;
    let meta = load_meta(auth.pool.as_ref(), key, now).await?;
    let Some(meta) = meta else {
        return Ok(Value::Array(Vec::new()));
    };
    if meta.r_type != TYPE_SET {
        return Ok(wrong_type());
    }

    let rows = sqlx::query("SELECT member FROM redis_set WHERE r_key = ?")
        .bind(key.as_ref())
        .fetch_all(auth.pool.as_ref())
        .await
        .map_err(map_sql_err)?;
    let mut out = Vec::with_capacity(rows.len());
    for row in rows {
        let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
        out.push(Value::Bulk(Bytes::from(member)));
    }
    Ok(Value::Array(out))
}

pub async fn scard(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    if cmd.args.len() != 1 {
        return Err(wrong_arity("SCARD"));
    }
    let auth = session.auth().await.ok_or(RespError::NoAuth)?;
    state.pools.touch(&auth.user);
    let key = arg_as_bytes(&cmd.args[0])?;
    let now = now_ms() as i64;
    let meta = load_meta(auth.pool.as_ref(), key, now).await?;
    let Some(meta) = meta else {
        return Ok(Value::Integer(0));
    };
    if meta.r_type != TYPE_SET {
        return Ok(wrong_type());
    }
    Ok(Value::Integer(meta.r_len))
}

pub async fn srandmember(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    if cmd.args.is_empty() {
        return Err(wrong_arity("SRANDMEMBER"));
    }
    let auth = session.auth().await.ok_or(RespError::NoAuth)?;
    state.pools.touch(&auth.user);
    let count = if cmd.args.len() >= 2 {
        Some(arg_as_i64(&cmd.args[1])?)
    } else {
        None
    };

    let key = arg_as_bytes(&cmd.args[0])?;
    let now = now_ms() as i64;
    let meta = load_meta(auth.pool.as_ref(), key, now).await?;
    let Some(meta) = meta else {
        return Ok(if count.is_some() {
            Value::Array(Vec::new())
        } else {
            Value::Null
        });
    };
    if meta.r_type != TYPE_SET {
        return Ok(wrong_type());
    }
    let len = meta.r_len;
    if len <= 0 {
        return Ok(if count.is_some() {
            Value::Array(Vec::new())
        } else {
            Value::Null
        });
    }

    match count {
        None => {
            let offset = random_index(len);
            let row = sqlx::query(
                "SELECT member FROM redis_set WHERE r_key = ? ORDER BY member LIMIT 1 OFFSET ?",
            )
            .bind(key.as_ref())
            .bind(offset)
            .fetch_optional(auth.pool.as_ref())
            .await
            .map_err(map_sql_err)?;
            let Some(row) = row else {
                return Ok(Value::Null);
            };
            let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
            Ok(Value::Bulk(Bytes::from(member)))
        }
        Some(n) if n >= 0 => {
            if n == 0 {
                return Ok(Value::Array(Vec::new()));
            }
            let fetch_all = n >= len;
            let rows = if fetch_all {
                sqlx::query("SELECT member FROM redis_set WHERE r_key = ? ORDER BY member")
                    .bind(key.as_ref())
                    .fetch_all(auth.pool.as_ref())
                    .await
                    .map_err(map_sql_err)?
            } else {
                let range = len - n + 1;
                let offset = random_index(range);
                sqlx::query(
                    "SELECT member FROM redis_set WHERE r_key = ? ORDER BY member LIMIT ? OFFSET ?",
                )
                .bind(key.as_ref())
                .bind(n)
                .bind(offset)
                .fetch_all(auth.pool.as_ref())
                .await
                .map_err(map_sql_err)?
            };
            let mut out = Vec::with_capacity(rows.len());
            for row in rows {
                let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
                out.push(Bytes::from(member));
            }
            if fetch_all {
                shuffle_slice(&mut out);
            }
            Ok(Value::Array(out.into_iter().map(Value::Bulk).collect()))
        }
        Some(n) => {
            let n = n.abs();
            let mut out = Vec::new();
            for _ in 0..n {
                let offset = random_index(len);
                let row = sqlx::query(
                    "SELECT member FROM redis_set WHERE r_key = ? ORDER BY member LIMIT 1 OFFSET ?",
                )
                .bind(key.as_ref())
                .bind(offset)
                .fetch_optional(auth.pool.as_ref())
                .await
                .map_err(map_sql_err)?;
                let Some(row) = row else {
                    break;
                };
                let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
                out.push(Value::Bulk(Bytes::from(member)));
            }
            Ok(Value::Array(out))
        }
    }
}

pub async fn spop(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    if cmd.args.is_empty() {
        return Err(wrong_arity("SPOP"));
    }
    let auth = session.auth().await.ok_or(RespError::NoAuth)?;
    state.pools.touch(&auth.user);
    let key = arg_as_bytes(&cmd.args[0])?;
    let now = now_ms() as i64;
    let meta = load_meta(auth.pool.as_ref(), key, now).await?;
    let Some(meta) = meta else {
        return Ok(Value::Null);
    };
    if meta.r_type != TYPE_SET {
        return Ok(wrong_type());
    }

    let count = if cmd.args.len() >= 2 {
        arg_as_i64(&cmd.args[1])?
    } else {
        1
    };
    if count <= 0 {
        return Ok(Value::Array(Vec::new()));
    }

    let len = meta.r_len;
    if len <= 0 {
        return Ok(Value::Null);
    }
    let fetch_all = count >= len;
    let rows = if fetch_all {
        sqlx::query("SELECT member FROM redis_set WHERE r_key = ? ORDER BY member")
            .bind(key.as_ref())
            .fetch_all(auth.pool.as_ref())
            .await
            .map_err(map_sql_err)?
    } else {
        let range = len - count + 1;
        let offset = random_index(range);
        sqlx::query("SELECT member FROM redis_set WHERE r_key = ? ORDER BY member LIMIT ? OFFSET ?")
            .bind(key.as_ref())
            .bind(count)
            .bind(offset)
            .fetch_all(auth.pool.as_ref())
            .await
            .map_err(map_sql_err)?
    };
    if rows.is_empty() {
        return Ok(Value::Null);
    }

    let mut members = Vec::with_capacity(rows.len());
    for row in &rows {
        let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
        members.push(Bytes::from(member));
    }
    if fetch_all {
        shuffle_slice(&mut members);
    }

    let mut qb = sqlx::QueryBuilder::new("DELETE FROM redis_set WHERE r_key = ");
    qb.push_bind(key.as_ref());
    qb.push(" AND member IN (");
    let mut separated = qb.separated(", ");
    for member in &members {
        separated.push_bind(member.as_ref());
    }
    qb.push(")");

    let mut tx = auth.pool.begin().await.map_err(map_sql_err)?;
    qb.build().execute(&mut *tx).await.map_err(map_sql_err)?;
    let removed = members.len() as i64;
    let res = sqlx::query("UPDATE redis_kv SET r_len = r_len - ? WHERE r_key = ? AND r_type = ?")
        .bind(removed)
        .bind(key.as_ref())
        .bind(TYPE_SET)
        .execute(&mut *tx)
        .await
        .map_err(map_sql_err)?;
    if res.rows_affected() > 0 {
        sqlx::query("DELETE FROM redis_kv WHERE r_key = ? AND r_type = ? AND r_len <= 0")
            .bind(key.as_ref())
            .bind(TYPE_SET)
            .execute(&mut *tx)
            .await
            .map_err(map_sql_err)?;
    }
    tx.commit().await.map_err(map_sql_err)?;

    if count == 1 {
        return Ok(Value::Bulk(members.remove(0)));
    }
    Ok(Value::Array(members.into_iter().map(Value::Bulk).collect()))
}

pub async fn sinter(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    set_op(cmd, state, session, SetOp::Inter, false).await
}

pub async fn sunion(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    set_op(cmd, state, session, SetOp::Union, false).await
}

pub async fn sdiff(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    set_op(cmd, state, session, SetOp::Diff, false).await
}

pub async fn sinterstore(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    set_op(cmd, state, session, SetOp::Inter, true).await
}

pub async fn sunionstore(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    set_op(cmd, state, session, SetOp::Union, true).await
}

pub async fn sdiffstore(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    set_op(cmd, state, session, SetOp::Diff, true).await
}

enum SetOp {
    Inter,
    Union,
    Diff,
}

async fn set_op(
    cmd: resp_async::Command,
    state: Arc<AppState>,
    session: Arc<crate::state::Session>,
    op: SetOp,
    store: bool,
) -> Result<Value, RespError> {
    if cmd.args.len() < if store { 2 } else { 1 } {
        return Err(wrong_arity(match (op, store) {
            (SetOp::Inter, true) => "SINTERSTORE",
            (SetOp::Union, true) => "SUNIONSTORE",
            (SetOp::Diff, true) => "SDIFFSTORE",
            (SetOp::Inter, false) => "SINTER",
            (SetOp::Union, false) => "SUNION",
            (SetOp::Diff, false) => "SDIFF",
        }));
    }
    let auth = session.auth().await.ok_or(RespError::NoAuth)?;
    state.pools.touch(&auth.user);

    let (dest, keys) = if store {
        let dest = arg_as_bytes(&cmd.args[0])?.clone();
        let mut keys = Vec::with_capacity(cmd.args.len() - 1);
        for arg in cmd.args.iter().skip(1) {
            keys.push(arg_as_bytes(arg)?.clone());
        }
        (Some(dest), keys)
    } else {
        let mut keys = Vec::with_capacity(cmd.args.len());
        for arg in cmd.args.iter() {
            keys.push(arg_as_bytes(arg)?.clone());
        }
        (None, keys)
    };

    let now = now_ms() as i64;
    let mut present_keys = Vec::new();
    for key in &keys {
        if let Some(meta) = load_meta(auth.pool.as_ref(), key, now).await? {
            if meta.r_type != TYPE_SET {
                return Ok(wrong_type());
            }
            present_keys.push(key.clone());
        }
    }

    if matches!(op, SetOp::Inter) && present_keys.len() != keys.len() {
        return Ok(if store {
            Value::Integer(0)
        } else {
            Value::Array(Vec::new())
        });
    }

    let members = match op {
        SetOp::Inter => query_intersection(auth.pool.as_ref(), &present_keys).await?,
        SetOp::Union => query_union(auth.pool.as_ref(), &present_keys).await?,
        SetOp::Diff => query_diff(auth.pool.as_ref(), &present_keys).await?,
    };

    if let Some(dest) = dest {
        store_set(auth.pool.as_ref(), &dest, &members).await?;
        return Ok(Value::Integer(members.len() as i64));
    }

    Ok(Value::Array(members.into_iter().map(Value::Bulk).collect()))
}

async fn query_intersection(pool: &MySqlPool, keys: &[Bytes]) -> Result<Vec<Bytes>, RespError> {
    if keys.is_empty() {
        return Ok(Vec::new());
    }
    let mut qb = sqlx::QueryBuilder::new("SELECT member FROM redis_set WHERE r_key IN (");
    let mut separated = qb.separated(", ");
    for key in keys {
        separated.push_bind(key.as_ref());
    }
    qb.push(") GROUP BY member HAVING COUNT(DISTINCT r_key) = ");
    qb.push_bind(keys.len() as i64);
    let rows = qb.build().fetch_all(pool).await.map_err(map_sql_err)?;
    let mut out = Vec::with_capacity(rows.len());
    for row in rows {
        let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
        out.push(Bytes::from(member));
    }
    Ok(out)
}

async fn query_union(pool: &MySqlPool, keys: &[Bytes]) -> Result<Vec<Bytes>, RespError> {
    if keys.is_empty() {
        return Ok(Vec::new());
    }
    let mut qb = sqlx::QueryBuilder::new("SELECT DISTINCT member FROM redis_set WHERE r_key IN (");
    let mut separated = qb.separated(", ");
    for key in keys {
        separated.push_bind(key.as_ref());
    }
    qb.push(")");
    let rows = qb.build().fetch_all(pool).await.map_err(map_sql_err)?;
    let mut out = Vec::with_capacity(rows.len());
    for row in rows {
        let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
        out.push(Bytes::from(member));
    }
    Ok(out)
}

async fn query_diff(pool: &MySqlPool, keys: &[Bytes]) -> Result<Vec<Bytes>, RespError> {
    if keys.is_empty() {
        return Ok(Vec::new());
    }
    let first = &keys[0];
    if keys.len() == 1 {
        let rows = sqlx::query("SELECT member FROM redis_set WHERE r_key = ?")
            .bind(first.as_ref())
            .fetch_all(pool)
            .await
            .map_err(map_sql_err)?;
        let mut out = Vec::with_capacity(rows.len());
        for row in rows {
            let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
            out.push(Bytes::from(member));
        }
        return Ok(out);
    }

    let mut qb = sqlx::QueryBuilder::new("SELECT member FROM redis_set WHERE r_key = ");
    qb.push_bind(first.as_ref());
    qb.push(" AND member NOT IN (");
    let mut first_union = true;
    for key in keys.iter().skip(1) {
        if !first_union {
            qb.push(" UNION ");
        }
        first_union = false;
        qb.push("SELECT member FROM redis_set WHERE r_key = ");
        qb.push_bind(key.as_ref());
    }
    qb.push(")");
    let rows = qb.build().fetch_all(pool).await.map_err(map_sql_err)?;
    let mut out = Vec::with_capacity(rows.len());
    for row in rows {
        let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
        out.push(Bytes::from(member));
    }
    Ok(out)
}

async fn store_set(pool: &MySqlPool, key: &Bytes, members: &[Bytes]) -> Result<(), RespError> {
    let mut tx = pool.begin().await.map_err(map_sql_err)?;
    delete_key_in_tx(&mut tx, key).await?;
    if members.is_empty() {
        tx.commit().await.map_err(map_sql_err)?;
        return Ok(());
    }

    sqlx::query(
        "INSERT INTO redis_kv (r_key, r_type, r_len, expires_at_ms) VALUES (?, ?, ?, NULL)",
    )
    .bind(key.as_ref())
    .bind(TYPE_SET)
    .bind(members.len() as i64)
    .execute(&mut *tx)
    .await
    .map_err(map_sql_err)?;

    let mut qb = sqlx::QueryBuilder::new("INSERT INTO redis_set (r_key, member) ");
    qb.push_values(members, |mut row, member| {
        row.push_bind(key.as_ref());
        row.push_bind(member.as_ref());
    });
    qb.build().execute(&mut *tx).await.map_err(map_sql_err)?;

    tx.commit().await.map_err(map_sql_err)?;
    Ok(())
}

pub async fn sscan(
    Cmd(cmd): Cmd,
    State(state): State<AppState>,
    SessionHandle(session): SessionHandle,
) -> Result<Value, RespError> {
    if cmd.args.len() < 2 {
        return Err(wrong_arity("SSCAN"));
    }
    let auth = session.auth().await.ok_or(RespError::NoAuth)?;
    state.pools.touch(&auth.user);
    let key = arg_as_bytes(&cmd.args[0])?;
    let now = now_ms() as i64;
    let meta = load_meta(auth.pool.as_ref(), key, now).await?;
    let Some(meta) = meta else {
        return Ok(Value::Array(vec![
            Value::Bulk(Bytes::from_static(b"0")),
            Value::Array(Vec::new()),
        ]));
    };
    if meta.r_type != TYPE_SET {
        return Ok(wrong_type());
    }

    let cursor = arg_as_bytes(&cmd.args[1])?;
    let mut count = 10i64;
    let mut pattern: Option<Bytes> = None;
    let mut i = 2;
    while i < cmd.args.len() {
        let mut token = arg_as_bytes(&cmd.args[i])?.to_vec();
        for b in &mut token {
            b.make_ascii_uppercase();
        }
        match token.as_slice() {
            b"MATCH" => {
                let next = cmd
                    .args
                    .get(i + 1)
                    .ok_or_else(|| RespError::invalid_data("ERR syntax error"))?;
                pattern = Some(arg_as_bytes(next)?.clone());
                i += 2;
            }
            b"COUNT" => {
                let next = cmd
                    .args
                    .get(i + 1)
                    .ok_or_else(|| RespError::invalid_data("ERR syntax error"))?;
                count = arg_as_i64(next)?;
                if count <= 0 {
                    return Err(RespError::invalid_data("ERR invalid COUNT"));
                }
                i += 2;
            }
            _ => return Err(RespError::invalid_data("ERR syntax error")),
        }
    }

    let rows = sqlx::query(
        "SELECT member FROM redis_set WHERE r_key = ? AND member > ? \
         ORDER BY member LIMIT ?",
    )
    .bind(key.as_ref())
    .bind(cursor.as_ref())
    .bind(count)
    .fetch_all(auth.pool.as_ref())
    .await
    .map_err(map_sql_err)?;

    let mut out = Vec::new();
    let mut next_cursor: Option<Bytes> = None;
    for row in &rows {
        let member: Vec<u8> = row.try_get("member").map_err(map_sql_err)?;
        next_cursor = Some(Bytes::from(member.clone()));
        if let Some(pattern) = &pattern
            && !glob_match(pattern.as_ref(), &member)
        {
            continue;
        }
        out.push(Value::Bulk(Bytes::from(member)));
    }

    let cursor_value = match next_cursor {
        Some(value) if rows.len() as i64 == count => value,
        _ => Bytes::from_static(b"0"),
    };
    Ok(Value::Array(vec![
        Value::Bulk(cursor_value),
        Value::Array(out),
    ]))
}