W3911 Sudoku Server

Within these castle walls be forged Mavens of Computer Science ...

— Merlin, The Coder

Background

A Sudoku board is made up of nine boxes. Boxes (container for nine cells) are listed from top-to-bottom, left-to-right indexed from zero. Cells are listed from top-to-bottom, left-to-right, indexed from zero. All valid payloads and responses must use well-formed JSON. “cells” is returned as follows: “cells”: [[<nine values from top-left>], [<nine values from top-middle>], …]

End Points

POST /games?difficulty=<difficulty>

Creates a new game and associated board

   Parameters: 
   difficulty: easy | medium | hard | hell

   Body: none

   Status code: 201 Created

   Response: ID (integer) of newly created game
   {"id":<id>}
   

   {"id": 728134}

   Errors:
   

   400 Bad Request (difficulty specified doesn't match requirements)

GET /games/<id>/cells?filter=<filter>

Returns the current cells for the specified game

   Parameters: 
   filter: all | repeated | incorrect

   Body: none

   Status code: 200 OK

   Response: {"board":
   [{"cells":[{"position":{"boxIndex":<boxIndex>,"cellIndex":<cellIndex>},"value":<value>}...
   

   {"board":
   [{"cells":[{"position":{"boxIndex":0,"cellIndex":0},"value":0},{"position":{"boxIndex":0,"cellIndex":1},"value":1},
              {"position":{"boxIndex":0,"cellIndex":2},"value":2},{"position":{"boxIndex":0,"cellIndex":3},"value":3},
              {"position":{"boxIndex":0,"cellIndex":4},"value":4},{"position":{"boxIndex":0,"cellIndex":5},"value":5},
              {"position":{"boxIndex":0,"cellIndex":6},"value":6},{"position":{"boxIndex":0,"cellIndex":7},"value":7},
              {"position":{"boxIndex":0,"cellIndex":8},"value":8}]},
    {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1},
              {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3},
              {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5},
              {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7},
              {"position":{"boxIndex":1,"cellIndex":8},"value":8}]},
    {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1},
              {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3},
              {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5},
              {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7},
              {"position":{"boxIndex":1,"cellIndex":8},"value":8}]},
    {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1},
              {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3},
              {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5},
              {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7},
              {"position":{"boxIndex":1,"cellIndex":8},"value":8}]},
    {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1},
              {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3},
              {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5},
              {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7},
              {"position":{"boxIndex":1,"cellIndex":8},"value":8}]},
    {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1},
              {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3},
              {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5},
              {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7},
              {"position":{"boxIndex":1,"cellIndex":8},"value":8}]},
    {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1},
              {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3},
              {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5},
              {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7},
              {"position":{"boxIndex":1,"cellIndex":8},"value":8}]},
    {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1},
              {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3},
              {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5},
              {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7},
              {"position":{"boxIndex":1,"cellIndex":8},"value":8}]},
    {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1},
              {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3},
              {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5},
              {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7},
              {"position":{"boxIndex":1,"cellIndex":8},"value":8}]}
 ]}

   Errors:
   

   400 Bad Request (filter specified doesn't match requirements)

PUT /games/<id>/cells/<boxIndex>/<cellIndex>

Place specified value at in game at boxIndex, cellIndex

   Parameters: 
   none

   Body: {"value":<value>}

   Status code: 200 OK

   Response: none
   

   none

   Errors:
   

   400 Bad Request (boxIndex is out of range 0 ... 8)
 400 Bad Request (cellIndex is out of range 0 ... 8)
 400 Bad Request (value is out of range 1 ... 9 or null)

JSON Encoding

CoderMerlin™ Code Explorer: W0000 (1) 🟢

Assembly

C

C++

Java

Python

Swift

import Foundation let board = Board() let encoder = JSONEncoder() guard let data = try? encoder.encode(board), let json = String(data: data, encoding: .utf8) else { fatalError("Failed to encode data into json.") } print(json) // Structure definitions struct Position: Codable { let boxIndex: Int let cellIndex: Int } struct Cell: Codable { let position: Position let value: Int? } struct Box: Codable { let cells: [Cell] init(boxIndex: Int) { var cells = [Cell]() for cellIndex in 0 ..< 9 { cells.append(Cell(position: Position(boxIndex: boxIndex, cellIndex: cellIndex), value: cellIndex)) } self.cells = cells } } struct Board: Codable { let board: [Box] init() { var board = [Box]() for boxIndex in 0 ..< 9 { board.append(Box(boxIndex: boxIndex)) } self.board = board } }

Hide Compilation Output Sync  

Broadcast  

JSON Decoding

CoderMerlin™ Code Explorer: W0000 (2) 🟢

Assembly

C

C++

Java

Python

Swift

import Foundation let json = #""" {"board": [{"cells":[{"position":{"boxIndex":0,"cellIndex":0},"value":0},{"position":{"boxIndex":0,"cellIndex":1},"value":1}, {"position":{"boxIndex":0,"cellIndex":2},"value":2},{"position":{"boxIndex":0,"cellIndex":3},"value":3}, {"position":{"boxIndex":0,"cellIndex":4},"value":4},{"position":{"boxIndex":0,"cellIndex":5},"value":5}, {"position":{"boxIndex":0,"cellIndex":6},"value":6},{"position":{"boxIndex":0,"cellIndex":7},"value":7}, {"position":{"boxIndex":0,"cellIndex":8},"value":8}]}, {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1}, {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3}, {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5}, {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7}, {"position":{"boxIndex":1,"cellIndex":8},"value":8}]}, {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1}, {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3}, {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5}, {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7}, {"position":{"boxIndex":1,"cellIndex":8},"value":8}]}, {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1}, {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3}, {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5}, {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7}, {"position":{"boxIndex":1,"cellIndex":8},"value":8}]}, {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1}, {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3}, {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5}, {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7}, {"position":{"boxIndex":1,"cellIndex":8},"value":8}]}, {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1}, {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3}, {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5}, {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7}, {"position":{"boxIndex":1,"cellIndex":8},"value":8}]}, {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1}, {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3}, {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5}, {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7}, {"position":{"boxIndex":1,"cellIndex":8},"value":8}]}, {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1}, {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3}, {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5}, {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7}, {"position":{"boxIndex":1,"cellIndex":8},"value":8}]}, {"cells":[{"position":{"boxIndex":1,"cellIndex":0},"value":0},{"position":{"boxIndex":1,"cellIndex":1},"value":1}, {"position":{"boxIndex":1,"cellIndex":2},"value":2},{"position":{"boxIndex":1,"cellIndex":3},"value":3}, {"position":{"boxIndex":1,"cellIndex":4},"value":4},{"position":{"boxIndex":1,"cellIndex":5},"value":5}, {"position":{"boxIndex":1,"cellIndex":6},"value":6},{"position":{"boxIndex":1,"cellIndex":7},"value":7}, {"position":{"boxIndex":1,"cellIndex":8},"value":8}]} ]} """# let decoder = JSONDecoder() guard let data = json.data(using: .utf8), let board: Board = try? decoder.decode(Board.self, from: data) else { fatalError("Failed to decode json into board.") } dump(board) // Structure definitions struct Position: Codable { let boxIndex: Int let cellIndex: Int } struct Cell: Codable { let position: Position let value: Int? } struct Box: Codable { let cells: [Cell] } struct Board: Codable { let board: [Box] }

Hide Compilation Output Sync  

Broadcast  

Issue Request from Client to Server

CoderMerlin™ Code Explorer: W0000 (3) 🟢

Assembly

C

C++

Java

Python

Swift

import Foundation import FoundationNetworking // Form the request var request = URLRequest(url: URL(string: "https://language-server.codermerlin.com/now")!) request.httpMethod = "GET" // Execute synchronously (uses extension in code below) let (data, response, error) = URLSession.shared.syncRequest(with: request) if let data = data, let string = String(data: data, encoding: .utf8) { print(string) } else if let error = error { print("Error: \(error)") } else { print("An unexpected error occurred.") } // Reference: https://stackoverflow.com/questions/26784315/can-i-somehow-do-a-synchronous-http-request-via-nsurlsession-in-swift extension URLSession { func syncRequest(with request: URLRequest) -> (Data?, URLResponse?, Error?) { var data: Data? var response: URLResponse? var error: Error? let dispatchGroup = DispatchGroup() let task = dataTask(with: request) { data = $0 response = $1 error = $2 dispatchGroup.leave() } dispatchGroup.enter() task.resume() dispatchGroup.wait() return (data, response, error) } }

Hide Compilation Output Sync  

Broadcast  

Server-side Query String Access

  let difficulty: String? = request.query["difficulty"]

Server-side Content Access for JSON

  app.put("value") { req -> String in
      struct CellValue: Decodable {
          let value: Int?
      }
      let cellValue = try req.content.decode(CellValue.self)
      return "Done"
  }

Server-side Parameter Access and Error Handling

    guard let boxIndex = req.parameters.get("boxIndex", as: Int.self),
        let cellIndex = req.parameters.get("cellIndex", as: Int.self) else {
        throw Abort(.badRequest, reason: "boxIndex and cellIndex MUST be integers")
    }

Server-side Returning "No Content"

  return Response(status: .noContent)

Conversion to Dynamic Library

• In a directory parallel to the root of your project, execute:

  git clone https://github.com/TheCoderMerlin/VaporShell

• Enter your project's root directory
• Execute the following:

  cp ../VaporShell/make.sh .
  cp ../VaporShell/Package.swift .
  cp ../VaporShell/dylib.manifest .
  cp -r ../VaporShell/Sources/CBase32 Sources/
  cp -r ../VaporShell/Sources/CBcrypt Sources/
  mkdir Sources/VaporShell
  mv Sources/App Sources/VaporShell/
  mv Sources/Run Sources/VaporShell/
  swift package clean
  rm .build -rf

• Remove the line "import App" from Sources/VaporShell/Run/main.swift
• Execute "dylibEmacs"