kevy — Python client

First-party Python client for kevy, the pure-Rust, Redis-compatible engine. One package ships both faces (contract §1.4): a blocking Client and an asyncio AsyncClient — the same shape as redis-py's redis + redis.asyncio.

pip install kevy

import kevy

# Remote — native RESP2/3 over TCP. Standard library only.
r = kevy.connect("kevy://127.0.0.1:6379")
r.set("k", "v")
assert r.get(b"k") == b"v"

# Asyncio — same package, same results.
ac = await kevy.AsyncClient.connect("kevy://127.0.0.1:6379")
await ac.set("k", "v")

# Embedded (in-process), over the C ABI with ctypes. Needs the engine —
# see below; this line raises a message naming where to get it otherwise.
c = kevy.connect("mem://app")        # or  file:///var/lib/app

The embedded engine

mem:// and file:// run kevy inside your process through libkevy_ffi, a per-platform native library. A Python wheel does not carry it: it would work on the handful of targets we happened to build and nowhere else, while the remote client above works everywhere CPython does. So the engine comes from the engine's own repository —

git clone https://github.com/goliajp/kevy
cd kevy && cargo build --release -p kevy-ffi   # → target/release/

— and is found automatically from a kevy checkout, or by pointing KEVY_FFI_LIB at the built library. Without it, the first embedded call raises an error saying exactly this. Nothing else in the API differs.

One URL, two transports (§1.1)

rediss:// / kevys:// (TLS) and redis://user:pass@host (AUTH) are rejected — kevy has neither.

Embedded door (§5)

kevy.open_mem() / kevy.open_persistent(dir) return a DB — the in-process store over libkevy_ffi, driven by ctypes (no C-extension build). Every verb is reachable through db.cmd(*argv) -> Reply; db.get / db.set are the scalar fast paths; db.subscribe(chan) gives a polled (next()) + blocking (wait(ms)) subscription. The library is located via $KEVY_FFI_LIB or the repo target/{release,debug} build.

Command families

Every family of the contract (§3): core string/generic, hash, list, set, sorted set, sorted-set algebra, hash-field TTL, declarative indexes (idx_*, remote-only) — with any other IDX.* subcommand reachable through the raw do(*argv) / idx_query_raw escape hatches — change feed (feed_*), pub/sub (Subscriber / AsyncSubscriber), transactions (Transaction), pipelines, blocking pops (blpop/brpop/bzpopmin), and the cluster client (ClusterClient). Bytes and str are both accepted; the wire is bytes (§7).

Errors (§2)

Raised as a KevyError hierarchy inspectable by type: StoreError (WrongTypeError, NotIntegerError, …), ProtocolError, IoError, UnsupportedError, InvalidInputError, NotFoundError, ReadOnlyError, TimedOutError, ClosedError.

Tests

pip install -e '.[test]'
pytest                       # embedded + remote (spawns a real kevy server)

Remote tests build and boot kevy on a temp port; they skip cleanly if the server binary is absent (cargo build --release -p kevy).