Swift API Server

API Server.swift

//
//  main.swift
//  SynopsisAPIServer
//
//  Created by vade on 4/12/21.
//


import Foundation
import Swifter
import CoreML
import Vision

func resizedImage(image:CGImage, for size: CGSize) -> CGImage? {

    let context = CGContext(data: nil,
                            width: Int(size.width),
                            height: Int(size.height),
                            bitsPerComponent: 32,
                            bytesPerRow: 32 * 4 * Int(size.width),
                            space: CGColorSpace(name: CGColorSpace.sRGB)!,
                            bitmapInfo: CGBitmapInfo(rawValue: CGImageAlphaInfo.noneSkipLast.rawValue)
                                .union(.floatComponents).rawValue  )
    context?.interpolationQuality = .low
    context?.draw(image, in: CGRect(origin: .zero, size: size))

    guard let scaledImage = context?.makeImage() else { return nil }
    
    return scaledImage
}



do {
    let server = HttpServer()// demoServer(try String.File.currentWorkingDirectory())
    server.listenAddressIPv4 = "10.0.1.156"
    try server.start()
    
    let config = MLModelConfiguration()
    config.computeUnits = .all
    
    var model:YOUR_CORE_ML_MODEL!
    do {
        model  = try YOUR_CORE_ML_MODEL(configuration: config)
    }
    catch {
        print("error loading model")
    }
    
    let analysis_queue = DispatchQueue.init(label: "analysis_queue")

    server["/testAfterBaseRoute"] = { request in
        return .ok(.htmlBody("ok !"))
    }

    server.POST["/api/v1/analyze_image"] = { request in
//            print("got request")
            var response = ""
            for multipart in request.parseMultiPartFormData() {
                guard let name = multipart.name, let fileName = multipart.fileName, let contentType = multipart.headers["content-type"]  else { continue }
                
                let body = multipart.body
                let imageData = Data(body)

                let provider = CGDataProvider(data: imageData as CFData)
                
                var image:CGImage? = nil
                
                if contentType == "image/png" {
                    image = CGImage(pngDataProviderSource: provider!, decode: nil, shouldInterpolate: false, intent: .defaultIntent)
                }
                else if content == "image/jpeg" {
                    image = CGImage(jpegDataProviderSource: provider!, decode: nil, shouldInterpolate: false, intent: .defaultIntent)
                }

                guard let img = image else {
                    print("no image bailing")
                    continue
                }

                guard let smallimg = resizedImage(image: img, for: CGSize(width: REQUIRED_IMAGE_WIDTH, height:REQUIRED_IMAGE_HEIGHT)) else {
                    print ("Cant resize image")
                    continue
                }
                
//                do {
//
////                    analysis_queue.sync {
                let semapher = DispatchSemaphore(value: 1)
                
                DispatchQueue.main.async {
                        do {
//                            print("making input")
                            let input =  try CinemaNet_3_15_5Input(ImageWith:smallimg)
                            let prediction = try model.prediction(input: input)
                            print(prediction.shot_type)
                            //                        print("running inference")
//                            print("fimished inference")
                            semapher.signal()
                        }
                        catch
                        {
                            print("error")
                            semapher.signal()
                        }

                    }
                    
                semapher.wait()
             
     
                response += "Name: \(name) File name: \(fileName) Size: \(multipart.body.count)<br>"
            }
            print(response)
            return HttpResponse.ok(.htmlBody(response))
            
    }

    
    if #available(OSXApplicationExtension 10.10, *) {
        try server.start(9080, forceIPv4: true)
    } else {
        // Fallback on earlier versions
    }

    print("Server has started ( port = \(try server.port()) ). Try to connect now...")

    RunLoop.main.run()

} catch {
    print("Server start error: \(error)")
}