Readme.md

Edgenda.AzureIoT.CameraCirculation.ConsoleApp

Console application which allows the fetch of traffic camera data fron Ville de Montréal Open Data Portal.

Context

For the Azure IoT Edge course, this console application allows the capture of live traffic camera images. The images are provided by the Ville de Montréal Open Data Portal Street Observation Cameras.

How to use

Clone the project and build the Edgenda.AzureIoT.CameraCirculation.ConsoleApp project. Launch the application using:

$ dotnet Edgenda.AzureIoT.CameraCirculation.ConsoleApp.dll
starting
running

The default settings are:

• hostname: localhost

  Environment variable bound: CAMERASERVER_ZMQ_SERVERHOSTNAME

• basePort: 15000

  Environment variable bound: CAMERASERVER_ZMQ_SERVERBASEPORT

Application Architecture

The application fetches the data from: http://ville.montreal.qc.ca/circulation/sites/ville.montreal.qc.ca.circulation/files/cameras-de-circulation.json

Data is cached therefore multiple calls won't be throttled by the provider.

Two 0MQ (ZeroMQ) sockets are available:

• Port: basePort (15000)

  Request/Response socket, sample payload:

  {
      "Name":"get-by-coordinates",
      "Parameters":[-73.532344350311,45.600982799511]
  }

  Sample client code:

      using NetMQ;
      using NetMQ.Sockets;
      using Newtonsoft.Json;
      using System;
  
      using (var testClientSocket = new RequestSocket($"tcp://{hostname}:{basePort}"))
      {
          testClientSocket.SendFrame("{\"Name\":\"get-by-coordinates\",\"Parameters\":-73.532344350311,45.600982799511]}");
          var response = testClientSocket.ReceiveFrameString();
      }

  Coordinates in Parameters are Longitude/Latitude.

  Returns the five (5) closest camera data:

  [
      {
          "nid":241,
          "url":"http://ville.montreal.qc.ca/circulation/map/9/241",
          "titre":"Rue Saint-Donat et rue Sherbrooke",
          "id-camera":4,
          "id-arrondissement":9,
          "description":null,
          "axe-routier-nord-sud":"Rue Saint-Donat",
          "axe-routier-est-ouest":"Rue Sherbrooke",
          "url-image-en-direct":"http://www1.ville.montreal.qc.ca/Circulation-Cameras/GEN4.jpeg",
          "url-video-en-direct":"http://ville.montreal.qc.ca/circulation/GEN4.mp4"
      }
      ...
  ]

• Port: basePort + 1 (15001)

  Unused at the moment.