An actor-based data layer, helping you build simple or complex stores for any iOS or Mac app. ?
If you find Bodega valuable I would really appreciate it if you would consider helping sponsor my open source work, so I can continue to work on projects like Bodega to help developers like yourself.
act as humble infrastructure for our city, and Bodega aims to do that as well. We appreciate what bodegas do for us, yet it’s their simplicity and prevalence that almost makes us forget they’re here.
Bodega is an actor-based library that started as a simple cache based on reading and writing files to/from disk with an incredibly simple API. Today Bodega offers a form of infrastructure that any app’s data layer can use. Whether you want to store Codable objects with ease, build caches, or interface with your API or services like CloudKit, it all works in just a few lines of code.
Bodega’s StorageEngine is at the heart of what’s possible. Conforming any database, persistence layer, or even an API server, to the StorageEngine protocol automatically provides an incredibly simple data layer for your app thanks to Bodega’s ObjectStorage. Rather than Data and databases developers interact with their app’s Swift types no matter what those may be, have a unified API, and concurrency handled out of the box.
Bodega is fully usable and useful on its own, but it’s also the foundation of Boutique. You can find a demo app built atop Boutique in the Boutique Demo folder, showing you how to make an offline-ready realtime updating SwiftUI app in only a few lines of code. You can read more about the thinking behind the architecture in this blog post exploring Boutique and the Model View Controller Store architecture.
Getting Started
Bodega provides two types of storage primitives for you, StorageEngine and ObjectStorage. A StorageEngine writes Data to a persistence layer, while ObjectStorage works with Swift types that conform to Codable. A StorageEngine can save items to disk, SQLite, or even your own database, while ObjectStorage offers a unified layer over StorageEngines, providing a single API for saving objects to any StorageEngine you choose. Bodega offers DiskStorageEngine and SQLiteStorageEngine by default, or you can even build a StorageEngine based on your app’s server or a service like CloudKit if you want a simple way to interface with your API. You can even compose storage engines to create a complex data pipeline that hits your API and saves items into a database, all in one API call. The possibilities are endless.
StorageEngines
// Initialize a SQLiteStorageEngine to save data to an SQLite database.
let storage = SQLiteStorageEngine(
directory: .documents(appendingPath: "Quotes")
)
// Alternatively Bodega provides a DiskStorageEngine out of the box too.
// It has the same API but uses the file system to store objects. ¹
let storage = DiskStorageEngine(
directory: .documents(appendingPath: "Quotes")
)
// CacheKeys can be generated from a String or URL.
// URLs will be reformatted into a file system safe format before writing to disk.
let url = URL(string: "https://redpanda.club/dope-quotes/dolly-parton")
let cacheKey = CacheKey(url: url)
let data = Data("Find out who you are. And do it on purpose. - Dolly Parton".utf8)
// Write data to disk
try await storage.write(data, key: cacheKey)
// Read data from disk
let readData = await storage.read(key: cacheKey)
// Remove data from disk
try await storage.remove(key: Self.testCacheKey)
¹ The tradeoffs of SQLiteStorageEngine vs. DiskStorageEngine are discussed in the StorageEngine documentation, but SQLiteStorageEngine is the suggested default because of it’s far superior performance, using the same simple API.
Bodega provides two different instances of StorageEngine out of the box, but if you want to build your own all you have to do is conform to the StorageEngine protocol. This will allow you to create a StorageEngine for any data layer, whether you want to build a CoreDataStorageEngine, a RealmStorageEngine, a KeychainStorageEngine, or even a StorageEngine that maps to your API. If you can read, write, or delete data, you can conform to StorageEngine.
public protocol StorageEngine: Actor {
func write(_ data: Data, key: CacheKey) async throws
func write(_ dataAndKeys: [(key: CacheKey, data: Data)]) async throws
func read(key: CacheKey) async -> Data?
func read(keys: [CacheKey]) async -> [Data]
func readDataAndKeys(keys: [CacheKey]) async -> [(key: CacheKey, data: Data)]
func readAllData() async -> [Data]
func readAllDataAndKeys() async -> [(key: CacheKey, data: Data)]
func remove(key: CacheKey) async throws
func remove(keys: [CacheKey]) async throws
func removeAllData() async throws
func keyExists(_ key: CacheKey) async -> Bool
func keyCount() async -> Int
func allKeys() async -> [CacheKey]
func createdAt(key: CacheKey) async -> Date?
func updatedAt(key: CacheKey) async -> Date?
}
ObjectStorage
Bodega’s most common usage is in Boutique, but you can also use it as a standalone cache. Any StorageEngine can read or write Data from your peristence layer, but ObjectStorage provides the ability to work with Swift types, as long as they conform to Codable. ObjectStorage has a very similar API to DiskStorage, but with slightly different function names to be more explicit that you’re working with objects and not Data.
// Initialize an ObjectStorage object
let storage = ObjectStorage(
storage: SQLiteStorageEngine(directory: . documents(appendingPath: "Quotes"))!
)
let cacheKey = CacheKey("churchill-optimisim")
let quote = Quote(
id: "winston-churchill-1",
text: "I am an optimist. It does not seem too much use being anything else.",
author: "Winston Churchill",
url: URL(string: "https://redpanda.club/dope-quotes/winston-churchill")
)
// Store an object
try await storage.store(quote, forKey: cacheKey)
// Read an object
let readObject: Quote? = await storage.object(forKey: cacheKey)
// Grab all the keys, which at this point will be one key, `cacheKey`.
let allKeys = await storage.allKeys()
// Verify by calling `keyCount`, both key-related methods are also available on `DiskStorage`.
await storage.keyCount()
// Remove an object
try await storage.removeObject(forKey: cacheKey)
Further Exploration
Bodega is very useful as a primitive for interacting with and peristing data, but it’s even more powerful when integrated into Boutique. Boutique is a Store and serves as the foundation of a Model View Controller Store architecture I’ve developed. MVCS brings together the familiarity and simplicity of the MVC architecture you know and love with the power of a Store, to give your app a simple but well-defined state management and data architecture.
If you’d like to learn more about how it works you can read about the philosophy in a blog post where I explore MVCS for SwiftUI, and you can find a reference implementation of an offline-ready realtime updating MVCS app powered by Boutique in this repo.
Feedback
This project provides multiple forms of delivering feedback to maintainers.
-
If you have a question about Bodega, we ask that you first consult the documentation to see if your question has been answered there.
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If you still have a question, enhancement, or a way to improve Bodega, this project leverages GitHub’s Discussions feature.
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If you find a bug and wish to report an issue would be appreciated.
Feedback
Requirements
- iOS 13.0+
- macOS 11.0
- Xcode 13.2+
Installation
Swift Package Manager
The Swift Package Manager is a tool for automating the distribution of Swift code and is integrated into the Swift build system.
Once you have your Swift package set up, adding Bodega as a dependency is as easy as adding it to the dependencies value of your Package.swift.
dependencies: [
.package(url: "https://github.com/mergesort/Bodega.git", .upToNextMajor(from: "1.0.0"))
]
Manually
If you prefer not to use SPM, you can integrate Bodega into your project manually by copying the files in.
About me
Hi, I’m Joe everywhere on the web, but especially on Twitter.
License
See the license for more information about how you can use Bodega.
Sponsorship
Bodega is a labor of love to help developers build better apps, making it easier for you to unlock your creativity and make something amazing for your yourself and your users. If you find Bodega valuable I would really appreciate it if you’d consider helping sponsor my open source work, so I can continue to work on projects like Bodega to help developers like yourself.
