86b54e1291
Move core, sync, and transit from platform-specific .clj/.cljs to shared .cljc files with reader conditionals. This enables testing the full sync logic on the JVM and using SyncedAtom from Clojure clients. Key changes: - PStore protocol (store.cljc) decouples core from storage backend - IDB store (store/idb.cljs) and memory store (store/memory.cljc) - SyncedAtom implements CLJ IDeref/IAtom/IRef + CLJS equivalents - Sync client uses java.net.http on CLJ, fetch on CLJS - SSE remains CLJS-only; JVM clients use polling - API change: store passed explicitly instead of pb/open - 7 new JVM tests: local ops, persistence, watches, two-client sync - 28 tests total, 87 assertions, all passing
Pocketbook
A Clojure-native synced atom. Offline-first key-value store with an atom interface that syncs to a SQLite-backed server over Transit.
(def conn (<! (pocketbook/open "my-app")))
(def todos (pocketbook/synced-atom conn "todo" {:server "http://localhost:8090/sync"}))
(swap! todos assoc "todo:1" {:text "Buy milk" :tags #{:groceries}})
@todos ;=> {"todo:1" {:text "Buy milk" :tags #{:groceries}}}
What it does
- Preserves Clojure types: keywords, sets, UUIDs, instants — no lossy JSON
- Works offline: reads/writes hit IndexedDB immediately, syncs when online
- Atom interface:
swap!,deref,add-watch— works with Reagent, Rum, or raw CLJS - ~500 lines: client (~300) + server (~200), no opaque dependencies
Quick start
Server
clj -M:server
# or: clj -M:server 8090 my-data.db
Starts on http://localhost:8090 with a SQLite file at pocketbook.db.
Client (CLJS)
(ns my-app.core
(:require [pocketbook.core :as pb]
[cljs.core.async :refer [go <!]]))
(go
(let [conn (<! (pb/open "my-app"))
todos (pb/synced-atom conn "todo"
{:server "http://localhost:8090/sync"})]
(<! (pb/ready? todos))
(swap! todos assoc "todo:1" {:text "Buy milk" :done false})
(add-watch todos :log (fn [_ _ _ new] (println (count new) "todos")))))
Architecture
Browser Server
┌─────────────┐ ┌──────────────┐
│ SyncedAtom │ ── Transit/HTTP ──▶ │ http-kit │
│ ↕ atom │ │ ↕ Transit │
│ ↕ IndexedDB│ ◀── Transit/HTTP ── │ ↕ Nippy │
│ (Transit) │ │ ↕ SQLite │
└─────────────┘ └──────────────┘
Sync protocol
- Pull:
GET /sync?group=todo&since=<epoch-ms>— returns changed docs - Push:
POST /sync— sends local changes with version numbers - Conflicts: server rejects stale writes, client accepts server value
Auth
Optional token-based auth:
(server/start! {:port 8090
:users {"alice" {:token "abc123" :groups #{"todo" "settings"}}
"bob" {:token "def456" :groups #{"todo"}}}})
Client passes token:
(pb/synced-atom conn "todo" {:server "http://localhost:8090/sync"
:token "abc123"})
Dependencies
| Layer | Library | Purpose |
|---|---|---|
| Server | next.jdbc + sqlite-jdbc | SQLite storage |
| Server | nippy | Binary serialization |
| Server | transit-clj | Wire format |
| Server | http-kit | HTTP server |
| Client | transit-cljs | Serialization (IDB + wire) |
| Client | core.async | Sync coordination |
Tests
# All server tests
clj -M:dev -e '(require (quote pocketbook.db-test) (quote pocketbook.transit-test) (quote pocketbook.server-test) (quote pocketbook.auth-test)) (clojure.test/run-all-tests #"pocketbook\..*")'
License
MIT