Einführung

#!/usr/bin/env node

// Example for Nodejs - JS
//
// 1. Connect to websocket-server
// 2. Check camera 1 is connected
// 3. If camera 1 is connected toggle the light
// 4. Take a jpg image and save it as file
// 5. Close connection
//
// Install dependencies:
//   npm install websocket
//


const W3CWebSocket = require('websocket').w3cwebsocket;
const http = require('http');
const fs = require('fs');

const RotoclearIp = "192.168.178.61"
const RotoclearApiPort = "80"
const ApiToken = "1a2B3c4D5e6f7G8h"
const WebsocketApiUrlWithAuth = "ws://" + RotoclearIp + ":" + RotoclearApiPort + "/api?token=" + ApiToken
const HttpCameraImageUrlWithAuth = "http://" + RotoclearIp + ":" + RotoclearApiPort + "/camera.jpeg?user=API-User&token=" + ApiToken
const imageName = 'myNewImage.jpg'

console.log("try to establish connection to ", WebsocketApiUrlWithAuth)
var connection = new W3CWebSocket(WebsocketApiUrlWithAuth);

function sendToAPI(message) {
  // Send message to api server. Only stringified json object is accepted
  connection.send(JSON.stringify(message));
}


connection.onerror = function (err) {
  console.log('Connection error', err.toString());
};

connection.onopen = function () {
  console.log('Connection successful established');
};

connection.onclose = function (ev) {
  console.log('Client closed', ev.reason);
};

connection.onmessage = function (ev) {
  if (typeof ev.data === "string") {
    // if data is of type string, then it is json
    var api_message = JSON.parse(ev.data);

    if (api_message["cam0Exists"]) {
      if(api_message["light0"]) {
        sendToAPI({ "light0": false });
      } else {
        sendToAPI({ "jpeg": true });
      }

      http.get(HttpCameraImageUrlWithAuth, (res) => {
        let data = [];
        console.log('Status Code:', res.statusCode);
        res.on('data', (chunk) => {
          data.push(chunk);
        });
        
        res.on('end', () => {
          const imageBuffer = Buffer.concat(data);
          fs.writeFileSync(imageName, imageBuffer);

          process.exit()
        });
        
      }); 
    } else {
      console.log("No camera head detected")
      process.exit()
    }
  } 
};

// Dotnet c# API Example
//
// 1. Connect to websocket-server
// 2. Check camera 1 is connected
// 3. If camera 1 is connected toggle the light
// 4. Take a jpg image and save it as file
//
// Install dotnetSDK:
//   see:  https://docs.microsoft.com/de-de/dotnet/core/install
// 
// Init project in current directory:
//   dotnet new console
// 
// copy the content to your Program.cs and replace the namespace "dotnet_websocket_api_example" with yours

using System.Text;
using System.Net.WebSockets;
using System.Text.Json;
using System.Net;

namespace dotnet_websocket_api_example
{
  class Program
  {
    const string ServerIp = "192.168.178.61";
    const int ServerPort = 80;
    const string APIToken = "1a2B3c4D5e6f7G8h";


    public static Task SendString(ClientWebSocket ws, String data)
    {
      var encoded = Encoding.UTF8.GetBytes(data);
      var buffer = new ArraySegment<Byte>(encoded, 0, encoded.Length);
      return ws.SendAsync(buffer, WebSocketMessageType.Text, true, CancellationToken.None);
    }

    public static async Task<String> ReadString(ClientWebSocket ws)
    {
      ArraySegment<Byte> buffer = new ArraySegment<byte>(new Byte[32000]);

      using (var ms = new MemoryStream())
      {
        while (true)
        {
          WebSocketReceiveResult result = await ws.ReceiveAsync(buffer, CancellationToken.None);
          ms.Write(buffer.ToArray(), buffer.Offset, result.Count);
          if (result.EndOfMessage) {
            break;
          }
        }

        ms.Seek(0, SeekOrigin.Begin);
        using (var reader = new StreamReader(ms, Encoding.UTF8))
        {
          return reader.ReadToEnd();
        }
      }
    }

    static async Task Main(string[] args)
    {
      // Define the cancellation token.
      using (var socket = new ClientWebSocket())
      {

        try
        {
          await socket.ConnectAsync(new Uri("ws://" + ServerIp + ":" + ServerPort + "/api?token=" + APIToken), CancellationToken.None);

          string systemStateMessage = await ReadString(socket);
          JsonDocument doc = JsonDocument.Parse(systemStateMessage);
          var systemStateJson = doc.RootElement;

          System.Console.WriteLine(systemStateJson.ToString());

          if (!systemStateJson.GetProperty("cam0Exists").GetBoolean()) {
            // toggle light
            if (systemStateJson.GetProperty("light0").GetBoolean()) 
            { 
              await SendString(socket, "{ \"light0\": false }");
            }
            else
            {
              await SendString(socket, "{ \"light0\": true }");
            }

            // # get jpeg and save it
            using (var client = new HttpClient(new HttpClientHandler { AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate }))
            {
                HttpResponseMessage response = await client.GetAsync("http://" + ServerIp + ":" + ServerPort + "/camera.jpeg?user=API-User&token=" + APIToken);
                var jpgBytes = await response.Content.ReadAsByteArrayAsync();
                File.WriteAllBytes("streamImage.jpg", jpgBytes);
            }
          }
          else
          {
            System.Console.WriteLine("No camera head detected");
          }
        }
        catch (Exception ex)
        {
          Console.WriteLine($"ERROR - {ex.Message}");
        }
      }
    }
  }
}

# Example in NIM - Use http api to get and set data
#
# 1. Connect to websocket-server
# 2. Fetch some information from the system (eg. light0, record, recordTime, pan0)
# 3. Disable light and move pan cursor from current position via post request
# 

import std/[strformat, json, httpclient]

const
  rotoclearIp = "192.168.178.61" 
  rotoclearApiPort = "80" 
  apiToken = "1a2B3c4D5e6f7G8h"
  urlWithAuthInQuery = fmt("http://{rotoclearIp}:{rotoclearApiPort}/api?token={apiToken}")

let
  client = newHttpClient()
  response = client.getContent(urlWithAuthInQuery & "&get=[light0,record,recordTime,pan0]")
  jsonResponse = response.parseJson()

echo jsonResponse.pretty()

# disable light and move pan cursor from current position via post request
let
  message = %*{ 
    "light0": false,
    "pan0": { # relative values
      "x": -20.0, 
      "y": -30.0
    }
  }

echo client.postContent(urlWithAuthInQuery, $message)