Bridge your JavaScript library for usage in Swift 🚀
dependencies: [
.package(url: "https://github.com/LinusU/JSBridge", from: "1.0.0"),
]
github "LinusU/JSBridge" ~> 1.0.0
foobar.js:
window.Foobar = {
add (a, b) {
return a + b
},
greet (name) {
return `Hello, ${name}!`
},
async fetch (url) {
const response = await fetch(url)
const body = await response.text()
return { status: response.status, body }
}
}
Foobar.swift:
struct FetchResponse: Decodable {
let status: Int
let body: String
}
class Foobar {
static internal let bridge: JSBridge = {
let libraryPath = Bundle.main.path(forResource: "foobar", ofType: "js")!
let libraryCode = try! String(contentsOfFile: libraryPath)
return JSBridge(libraryCode: libraryCode)
}()
static func add(_ lhs: Int, _ rhs: Int) -> Promise<Int> {
return Foobar.bridge.call(function: "Foobar.add", withArgs: (lhs, rhs)) as Promise<Int>
}
static func greet(name: String) -> Promise<String> {
return Foobar.bridge.call(function: "Foobar.greet", withArg: name) as Promise<String>
}
static func fetch(url: URL) -> Promise<FetchResponse> {
return Foobar.bridge.call(function: "Foobar.fetch", withArg: url) as Promise<FetchResponse>
}
}
Create a new JSBridge
instance, with the supplied library source code.
The libraryCode
should be a string of JavaScript that attaches one or more functions to the window
object. These functions can then be called using the call
method.
Call a function without any arguments, ignoring the return value. The returned promise will settle once the function have completed running.
Call a function without any arguments. The returned promise will settle with the return value of the function.
Call a function with a single argument, ignoring the return value. The returned promise will settle once the function have completed running.
Call a function with a single argument. The returned promise will settle with the return value of the function.
Call a function with multiple arguments, ignoring the return value. The returned promise will settle once the function have completed running.
call<Result: Decodable, A: Encodable, B: Encodable, ...>(function: String, withArgs: (A, B, ...)) -> Promise<Result>
Call a function with multiple arguments. The returned promise will settle with the return value of the function.
To be able to use JSBridge on iOS, you need to give JSBridge a hook to your view hierarchy. Otherwise the WKWebView
will get suspended by the OS, and your Promises will never settle.
This is accomplished by using the setGlobalUIHook
function before instantiating any JSBridge
instances.
App:
// Can be called from anywhere, e.g. your AppDelegate
JSBridge.setGlobalUIHook(window: UIApplication.shared.windows.first)
App Extension:
// From within your root view controller
JSBridge.setGlobalUIHook(viewController: self)
The Xcode project is generated automatically from project.yml
using XcodeGen. It's only checked in because Carthage needs it, do not edit it manually.
$ mint run yonaskolb/xcodegen
💾 Saved project to JSBridge.xcodeproj