README.md

PowerSync encryption demo

A tiny app opening an encrypted database with PowerSync.

This example only opens a local database and does not setup a sync client. Since encryption happens at a low level using SQLite3 Multiple Ciphers, all regular PowerSync APIs are available for encrypted databases too.

Setup

PowerSync has no builtin encryption primitives, but can be made to work with SQLite3 Multiple Ciphers (sqlite3mc). By using the initialStatements parameter when opening databases, you can run PRAGMA key statements to configure encryption.

To use sqlite3mc instead of regular sqlite3, note that PowerSync depends on this project to compile and link SQLite into your app. To support encryption, enable the Encryption trait for that package. Since XCode doesn't support package traits, the workaround is to create a SwiftPM project in your XCode project (called helper/ in this demo). In helper/Package.swift, depend on CSQLite with the Encryption trait:

// swift-tools-version: 6.2
import PackageDescription

let package = Package(
    name: "helper",
    products: [
        // Products define the executables and libraries a package produces, making them visible to other packages.
        .library(
            name: "helper",
            targets: ["helper"]
        ),
    ],
    dependencies: [
        .package(url: "https://github.com/powersync-ja/CSQLite.git", exact: "3.51.2", traits: ["Encryption"]),
    ],
    targets: [
        .target(
            name: "helper",
            dependencies: [.product(name: "CSQLite", package: "CSQLite")]
        ),
    ]
)

Note that Sources/helper/helper.swift can be an empty file, but it needs to exist for this to compile.

Next, add a dependency to this local project from XCode and resolve packages. This will enable your entire app, including the PowerSync framework, to use sqlite3mc.

Finally, add initialStatements to encrypt databases:

let ps = PowerSyncDatabase(
    schema: yourSchema,
    initialStatements: ["pragma key = 'TODO: your key'"]
)