JSONRPCKit is a JSON-RPC 2.0 library purely written in Swift.
// Generating request JSON
let batchFactory = BatchFactory(version: "2.0", idGenerator: NumberIdGenerator())
let request = Subtract(minuend: 42, subtrahend: 23)
let batch = batchFactory.create(request)
batch.requestObject // ["jsonrpc": "2.0", "method": "subtract", "params": [42, 23], "id": 1]
// Parsing response JSON
let responseObject: Any = ["jsonrpc": "2.0", "result": 19, "id": 1]
let response = try! batch.responses(from: responseObject)
response // 19 (type of response is inferred from SubtractRequest.Response)- Swift 4.0 or later
- iOS 8.0 or later
- macOS 10.9 or later
- watchOS 2.0 or later
- tvOS 9.0 or later
- Define request type
- Generate request JSON
- Parse response JSON
First of all, define a request type that conforms to Request.
struct Subtract: JSONRPCKit.Request {
typealias Response = Int
let minuend: Int
let subtrahend: Int
var method: String {
return "subtract"
}
var parameters: Any? {
return [minuend, subtrahend]
}
func response(from resultObject: Any) throws -> Response {
if let response = resultObject as? Response {
return response
} else {
throw CastError(actualValue: resultObject, expectedType: Response.self)
}
}
}To generate request JSON, pass Request instances to BatchFactory instance, which has common JSON-RPC version and identifier generator.
When BatchFactory instance receives request(s), it generates identifier(s) for the request(s) and request JSON by combining id, version, method and parameters.
let batchFactory = BatchFactory(version: "2.0", idGenerator: NumberIdGenerator())
let request1 = Subtract(minuend: 42, subtrahend: 23)
let request2 = Subtract(minuend: 23, subtrahend: 42)
let batch = batchFactory.create(request1, request2)The request JSON is available in batch.requestObject. It looks like below:
[
{
"method" : "subtract",
"jsonrpc" : "2.0",
"id" : 1,
"params" : [
42,
23
]
},
{
"method" : "subtract",
"jsonrpc" : "2.0",
"id" : 2,
"params" : [
23,
42
]
}
]Suppose that following JSON is returned from server:
[
{
"result" : 19,
"jsonrpc" : "2.0",
"id" : 1,
"status" : 0
},
{
"result" : -19,
"jsonrpc" : "2.0",
"id" : 2,
"status" : 0
}
]To parse response object, execute responses(from:) of Batch instance.
When responses(from:) is called, Batch finds corresponding response object by comparing request id and response id.
After it find the response object, it executes responses(from:) of Response to get Request.Response from the response object.
let responseObject = ...
let (response1, response2) = try! batch.responses(from: responseObject)
print(response1) // 19
print(response2) // -19JSON-RPC over HTTP by APIKit
APIKit is a type-safe networking abstraction layer.
APIKit also has RequestType that represents HTTP request.
import APIKit
struct MyServiceRequest<Batch: JSONRPCKit.Batch>: APIKit.Request {
let batch: Batch
typealias Response = Batch.Responses
var baseURL: URL {
return NSURL(string: "https://api.example.com/")!
}
var method: HTTPMethod {
return .post
}
var path: String {
return "/"
}
var parameters: Any? {
return batch.requestObject
}
func response(from object: Any, urlResponse: HTTPURLResponse) throws -> Response {
return try batch.responses(from: object)
}
}let batchFactory = BatchFactory(version: "2.0", idGenerator: NumberIdGenerator())
let request1 = Subtract(minuend: 42, subtrahend: 23)
let request2 = Subtract(minuend: 23, subtrahend: 42)
let batch = batchFactory.create(request1, request2)
let httpRequest = MyServiceRequest(batch: batch)
Session.sendRequest(httpRequest) { result in
switch result {
case .Success(let response1, let response2):
print(response1.count) // CountCharactersResponse
print(response2.count) // CountCharactersResponse
case .Failure(let error):
print(error)
}
}JSONRPCKit is released under the MIT License.