swift-cdb

A Swift wrapper for the CDB (Constant Database) implementation from howerj/cdb, providing a native Swift interface for creating and querying constant key-value databases.

Add this package to your Swift project dependencies:

// In your Package.swift
dependencies: [
    .package(url: "https://github.com/aisk/swift-cdb.git", from: "0.1.0"),
]

import CDB

// Open a CDB file and read values
do {
    let db = try CDB(filename: "example.cdb", mode: .read)

    // Read string value
    let value = try db.string(forKey: "some_key")
    print("Value: \(value ?? "not found")")

    try db.close()
} catch {
    print("Error: \(error)")
}

• init(filename: String, mode: CDB.AccessMode) throws - Open a CDB file
• init(fileURL: URL, mode: CDB.AccessMode) throws - Open a CDB file URL
• add(key: String, value: String) throws - Add a string value
• add(key: String, value: Data) throws - Add binary data
• add(key: Data, value: String) throws - Add a string value with a binary key
• add(key: Data, value: Data) throws - Add a binary key and value
• string(forKey: String, at index: UInt64 = 0) throws -> String? - Get a string value
• string(forKey: Data, at index: UInt64 = 0) throws -> String? - Get a string value using a binary key
• data(forKey: String, at index: UInt64 = 0) throws -> Data? - Get binary data
• data(forKey: Data, at index: UInt64 = 0) throws -> Data? - Get binary data using a binary key
• count(key: String) throws -> UInt64 - Count values for a key
• count(key: Data) throws -> UInt64 - Count values for a binary key
• forEach(_:) throws - Visit all keys and values as strings
• forEachData(_:) throws - Visit all keys and values without decoding
• close() throws - Close the database
• withDatabase(filename:mode:_:) throws - Use a database within a managed scope
• withDatabase(fileURL:mode:_:) throws - Use a file URL within a managed scope
• subscript(key: String) throws -> String? - Dictionary-like access

• CDB.AccessMode.read - Open for reading only
• CDB.AccessMode.write - Open for writing (creates new database)

A CDB instance is not thread-safe. Serialize all operations on the same instance, including close(). Separate CDB instances may be used concurrently.

Do not call close() from inside a forEach callback.

String APIs require valid UTF-8 and throw CDBError.invalidUTF8 when stored bytes cannot be decoded. Use data(forKey:) or forEachData(_:) for arbitrary binary content.

This project is licensed under the same terms as the original CDB library.