routes.swift

import Vapor
import Redis


struct Counter: Content {
    let id: UUID
    let name: String
    let value: Int
}


struct CreateCounterRequest: Content {
    let name: String
    let value: Int
}


struct GetCounterResponse: Content {
    let counter: Counter
}


struct UpdateCounterRequest: Content {
    let name: String
    let value: Int
}


func routes(_ app: Application) throws {
    app.get { req in
        return "It works!"
    }

    app.get("hello") { req -> String in
        return "Hello, world!"
    }

    // Create a counter
    
    app.post("user", ":userId", "counter") { req -> EventLoopFuture<Counter> in
        guard let userId = req.parameters.get("userId", as: UUID.self) else {
            throw Abort(.notFound)
        }

        guard let createCounterRequest = try? req.content.decode(CreateCounterRequest.self) else {
            throw Abort(.badRequest)
        }

        let counter = Counter(id: UUID(), name: createCounterRequest.name, value: createCounterRequest.value)
        return app.redis.set("\(userId):\(counter.id)", toJSON: counter)
            .flatMap { req.eventLoop.makeSucceededFuture(counter) }
    }
    
    // Get a counter
    
    app.get("user", ":userId", "counter", ":counterId") { req -> EventLoopFuture<GetCounterResponse> in
        guard let userId = req.parameters.get("userId", as: UUID.self), let counterId = req.parameters.get("counterId", as: UUID.self) else {
            throw Abort(.badRequest)
        }
        
        return app.redis.get("\(userId):\(counterId)", asJSON: Counter.self)
            .unwrap(or: Abort(.notFound))
            .map { GetCounterResponse(counter: $0) }
    }
    
    // Update a counter
    
    app.put("user", ":userId", "counter", ":counterId") { req -> EventLoopFuture<GetCounterResponse> in
        guard let userId = req.parameters.get("userId", as: UUID.self), let counterId = req.parameters.get("counterId", as: UUID.self) else {
            throw Abort(.badRequest)
        }
        
        guard let updateCounterRequest = try? req.content.decode(UpdateCounterRequest.self) else {
            throw Abort(.notFound)
        }
        
        return app.redis.get("\(userId):\(counterId)", asJSON: Counter.self).flatMap { counter in
            guard let counter = counter else {
                return req.eventLoop.future(error: Abort(.notFound))
            }
            
            let updatedCounter = Counter(id: counter.id, name: updateCounterRequest.name, value: updateCounterRequest.value)
            
            return app.redis.set("\(userId):\(counter.id)", toJSON: updatedCounter)
                .flatMap { req.eventLoop.makeSucceededFuture(GetCounterResponse(counter: updatedCounter)) }
        }
    }
}