jkatzer / pythoncodable

Swift framework to efficiently bridge objects from Python to Swift.

PythonCodable

Swift framework to efficiently bridge objects from Python to Swift.

Requirements

PythonCodable requires Swift 5 or higher.

Usage

PythonCodable builds on PythonKit to allow bridging arbitrary Python objects into Swift types efficiently using PythonDecoder:

import PythonKit
import PythonCodable

// 1. Get a valid Python object:

let urllibParse = Python.import("urllib.parse")
let pythonParsedURL = urllibParse.urlparse("http://www.cwi.nl:80/%7Eguido/Python.html")

print(pythonParsedURL)               // ParseResult(scheme='http', netloc='www.cwi.nl:80'...
print(Python.type(pythonParsedURL))  // <class 'urllib.parse.ParseResult'>

// 2. Define a compatible Swift struct conforming to `Decodable`:

struct ParsedURL: Decodable {
    let scheme: String
    let netloc: String
    let path: String
    let params: String?
    let query: String?
    let fragment: String?
}

// 3. Decode the Python object as a Swift type using `PythonDecoder`:

let parsedURL = try PythonDecoder.decode(ParsedURL.self, from: pythonParsedURL)

XCTAssertEqual(parsedURL.scheme, "http")
XCTAssertEqual(parsedURL.netloc, "www.cwi.nl:80")
XCTAssertEqual(parsedURL.path, "/%7Eguido/Python.html")

PythonDecoder supports multiple Python to Swift type conversions:

• int to Int
• float to Double
• bool to Bool
• None to nil
• list[t] to Array<T> where t is one of the supported types.
• dict[k, v] to Dictionary<K, T> where k is a str and v is one of the supported types.
• object to Any : Decodable where object is a dict, a named tuple or an object with a dictionary representation.

Swift Package Manager

Add the following dependency to your Package.swift manifest:

.package(url: "https://github.com/pvieito/PythonCodable.git", .branch("master")),

References

• PythonKit