Tauri v2: Store Plugin

A JSON-backed key-value store that survives restarts. One store per file; files live under app_data_dir. Cheap, async, shared between Rust and JS — pick it for settings, last-window-state, simple caches.

Not the right tool for: lists with >~1k entries, anything queryable, anything you’d want to sort or filter without loading the whole file. Use tauri-plugin-sql for that.

Install

npm run tauri add store

Manual: tauri-plugin-store = "2", @tauri-apps/plugin-store, .plugin(tauri_plugin_store::Builder::new().build()).

JS API

import { load } from '@tauri-apps/plugin-store';

// Lazy: file is created on first save; not read off disk until first access.
const store = await load('settings.json', { autoSave: true });

await store.set('theme', 'dark');
await store.set('lastWindow', { x: 100, y: 100, w: 800, h: 600 });

const theme = await store.get<string>('theme');     // 'dark'
const has   = await store.has('theme');             // true
await store.delete('lastWindow');
await store.clear();

// With autoSave: false, persist manually:
await store.save();

load() returns the same handle for the same path — it’s cached. Subsequent calls hit the in-memory copy.

Option	Default	Meaning
autoSave	false	If a number, debounces saves by that many ms; true ≈ 100ms
defaults	none	Seed values used on first creation only
serializeFn / deserializeFn	JSON	Override the codec (advanced)

Stores also auto-persist on graceful app exit. Don’t rely on this for crashes.

Rust API

use tauri_plugin_store::StoreExt;

#[tauri::command]
async fn set_theme(app: tauri::AppHandle, theme: String) -> Result<(), String> {
    let store = app.store("settings.json").map_err(|e| e.to_string())?;
    store.set("theme", serde_json::Value::String(theme));
    store.save().map_err(|e| e.to_string())?;
    Ok(())
}

app.store(path) returns an Arc<Store<R>>. Values are serde_json::Value — convert at the edges:

let theme: String = store
    .get("theme")
    .and_then(|v| v.as_str().map(String::from))
    .unwrap_or_else(|| "system".into());

File location

OS	Path
macOS	~/Library/Application Support/<bundle id>/<file>
Linux	~/.local/share/<bundle id>/<file>
Windows	%APPDATA%\<bundle id>\<file>

The exact resolved dir is app.path().app_data_dir(). Use relative names in load() — never absolute paths; you’d skip the per-app sandbox.

JSON-only

Anything you set() is serialized via JSON. Concretely:

• ✅ string, number, boolean, null, plain object, array
• ❌ Date — silently becomes "2024-…" string round-trip; convert explicitly
• ❌ Map/Set — becomes {} / []
• ❌ Uint8Array — becomes a JSON object of indices; for binary use the fs plugin
• ❌ functions, class instances — lose prototype, often {}

If you find yourself reaching for one of these, that’s a sign you want SQL.

Migrations

There’s no built-in schema migration. Two practical patterns:

// 1) version key + manual upgrades on load
const VERSION = 2;
const store = await load('settings.json', { autoSave: true });
const v = (await store.get<number>('__v')) ?? 0;
if (v < 1) {
  // v0 → v1: rename `colorMode` → `theme`
  const old = await store.get<string>('colorMode');
  if (old) { await store.set('theme', old); await store.delete('colorMode'); }
}
if (v < 2) { /* v1 → v2 … */ }
await store.set('__v', VERSION);

// 2) namespaced files, no migration — bump the filename
const store = await load('settings.v2.json', { autoSave: true });

The second pattern is the simplest correct choice when shapes change a lot.

Store vs SQL

Need	Store	SQL
App settings, last-used window	yes	overkill
<100 small records	yes	works
Querying / filtering / sorting	reload-and-walk	yes
Concurrent writers (multiple windows)	last-write-wins	proper transactions
Schema migrations	manual	first-class
Binary blobs	no	yes

Permission

store:default covers normal use. Grant it in the capability:

{ "permissions": ["store:default"] }

Templates

• templates/setup.rs — plugin init + a Rust command reading the store.
• templates/usage.ts — load / get / set / migrate pattern.
• templates/capability.json — minimal store permission.

Related

• tauri-plugins-fs — when you need raw file I/O instead of KV.
• tauri-plugins-sql — when KV stops scaling.
• tauri-plugins — overall plugin decision matrix.