rdb-rs

Fast parser for Redis RDB dump files, as a Rust library, a command line tool and a Python package.

Use it to look inside a Redis snapshot without loading it into Redis: inspect or export keys, convert a dump to JSON, replay it as Redis commands, or feed it into your own analysis code.

Supported Redis versions

RDB format versions 1 to 13, i.e. dumps written by Redis up to 8.6. CI parses dumps produced by real Redis 6.2, 7.0, 7.2, 7.4, 8.0, 8.2, 8.4 and 8.6 servers.

Files from newer Redis versions are rejected with an "unsupported RDB version" error rather than misread.

Command line

cargo install rdb

Usage: rdb [options] dump.rdb

Options:
  -f, --format <FORMAT>  Format to output. Valid: json, plain, nil, protocol
  -k, --keys <KEYS>      Keys to show. Can be a regular expression
  -d, --databases <DB>   Database to show. Can be specified multiple times
  -t, --type <TYPE>      Type to show. Can be specified multiple times
  -o, --output <FILE>    Output file path. If not specified, writes to stdout

Types are string, list, set, sortedset and hash.

$ rdb --format json --keys '^(str|zset|hfe_small)$' dump.rdb
[{"str":"hello","zset":{"a":"1","b":"2"},"hfe_small":{"f1":"v1","f2":"v2","f3":"v3"}}]

$ rdb --format plain --keys '^zset$' dump.rdb | grep zset
db=0 zset[0] -> {a, score=1}
db=0 zset[1] -> {b, score=2}

$ rdb --format protocol dump.rdb | redis-cli --pipe   # replay into another server

json prints one object per database, plain one line per value, protocol emits RESP commands (SET, RPUSH, HSET, SADD, ZADD, PEXPIREAT) and nil only validates the file. Errors go to stderr with exit code 1.

Rust

[dependencies]
rdb = "0.4"

use std::fs::File;
use std::io::BufReader;
use rdb::{RdbDecoder, RdbValue, filter::Simple};

fn main() -> Result<(), rdb::RdbError> {
    let file = BufReader::new(File::open("dump.rdb")?);
    for item in RdbDecoder::new(file, Simple::new())? {
        if let RdbValue::String { key, value, expiry } = item? {
            println!("{:?} = {:?} (expires {:?})", key, value, expiry);
        }
    }
    Ok(())
}

rdb::parse(reader, formatter, filter) renders a dump through one of the built-in formatters or your own Formatter implementation. API documentation: https://docs.rs/rdb.

Python

pip install rdb-py

Wheels are published for Linux, macOS and Windows, for CPython 3.10+ (including free-threaded 3.14t).

import rdb

decoder = rdb.RdbDecoder("dump.rdb")  # str or pathlib.Path
print(decoder.version)                # RDB format version, e.g. 13

for item in decoder:
    if item["type"] == "hash":
        print(item["key"], item["values"], item["expiry"])

Each item is a dict with a type field. Keys and values are bytes; expiry is a Unix timestamp in milliseconds or None.

The package ships type hints (TypedDict per item type). Opening a missing file raises FileNotFoundError; a file that is not a supported RDB file, or malformed data during iteration, raises ValueError.

Development

cargo test                                   # unit, fixture, CLI and Redis container tests (needs Docker)
cargo test -- --skip test_redis_protocol     # without Docker
uv sync && uv run pytest                     # Python bindings

tests/dumps/*.rdb are compared byte-for-byte against the expected outputs in tests/dumps/{json,plain,protocol}/. To add a fixture, put the dump there and generate the three outputs with cargo run -- --format <format> -o tests/dumps/<format>/<name>.<format> tests/dumps/<name>.rdb, then check them by hand.

The file format is described in docs/RDB_File_Format.md and its evolution in docs/RDB_Version_History.md. Changes are listed in the changelog.

History

rdb-rs was written by Jan-Erik Rediger (badboy/rdb-rs, now archived), inspired by redis-rdb-tools. Since 2024 it is maintained here by Tim Bauer. Bugs and ideas: issues.

License

MIT, see LICENSE.