tur-tourist-session-valkey

Valkey-backed session store for tur-tourist-session.

The core tourist-session spice has no native dependencies and ships an in-memory store and a file store. This sibling spice adds a third backend — Valkey/Redis — without pulling the valkey/hiredis native dependency into every session-using app. Reach for it once a single process's in-memory store or one machine's file store no longer fits: multi-process, multi-server, or restart-surviving deployments.

It plugs into the same Store vtable, so installation is identical to the built-in stores:

(import valkey/client          :refer [client-connect client-close])
(import tourist-session-valkey/store :refer [valkey-store-new])
(import session/mw             :refer [session-mw])
(import session/config         :refer [default-session-config])

(defn main [] : int
  (let [c     (ok-val (client-connect "127.0.0.1" 6379))
        store (valkey-store-new c "sess" 86400)]   ;; client, key prefix, max-age
    (let [srv (tourist 3000
                (session-mw store (default-session-config))
                (get! "/" home))]
      ;; ... serve ...
      (client-close c)   ;; the store borrows the client; you own its lifecycle
      0)))

How it stores sessions

• Key layout. Each session is one key, <prefix>:<session-id>.
• Serialization. The value is the same JSON envelope the file store writes ({"expires_at":N,"data":{...}}), produced by the shared session/serde codec in core tourist-session.
• Expiry. The key is given a TTL equal to the session's max-age, so expired sessions vacate on their own — no sweeper. A max-age of 0 ("until browser close") has no natural Valkey TTL, so the key falls back to a documented 24h default.
• Client lifecycle. valkey-store-new borrows the client and never closes it. Keep it alive for the life of the server and client-close it on shutdown.

API

;; client  -- borrowed Valkey client (caller owns lifecycle)
;; prefix  -- key namespace, e.g. "sess"
;; max-age -- session lifetime in seconds (match SessionConfig's max-age)
(defn valkey-store-new [^borrow client : Client prefix : cstr max-age : int] : Store)

Tests

tests/ drives a real save → load → delete cycle against a Valkey on 127.0.0.1:6379. The test is self-skipping: with no server reachable it prints a skip notice and passes, so tur test is green on a machine without Valkey. To run it for real, start a server first:

valkey-server --port 6379 &     # or: redis-server
tur test tests/tourist-session-valkey