Delphi and WebSoket
WebSocket is a technology that allows a bidirectional interaction between server and client, you will tell me, nothing new with a socket connection of the 90’s we did the same thing. True!!!
The thing that makes this technology very advantageous is that first of all, it implements standards in data transmission and use protocols but mainly it can be integrated into a Web application in a very simple way using Javascript, JQuery or any JS framework.
To understand the use and ease of implementation of the WebSockets via JS, just look at the mozzila tutorial at this link :
https://developer.mozilla.org/it/docs/WebSockets/Writing_WebSocket_client_applications
Below is a wonderful example video on how to implement webSoket published by Stas Piter
Also very interesting is the article by Jon L. Aasenden : Writing a Delphi WebSocket server and Smart Mobile Client in 15 minutes
Among the various solutions for implementing webSokets, the one provided by the company should be noted esegece which provides commercial support for this type of implementation with Delphi.
Una cosa interessante è la possibilità di poter simulare un comportamento simile ad MQTT semplicamente giocando sulla url di richiesta:
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ws.onmessage = function(event) { console.log(`[srv message]: ${event.data}`); }; ƒ (event) { console.log(`[srv message]: ${event.data}`); } ws.send("ciao"); undefined VM633:2 [srv message]: Ricevuto: (SID: /mychat/ivan )ciao |
Server side code:
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// https://it.javascript.info/websocket procedure TdmWS.sgcWebSocketServerMessage(Connection: TsgcWSConnection; const Text: string); begin Connection.WriteData('Ricevuto: (SID: ' + Connection.URL + ' )' + Text); end; |
