Example TcHmi User Switching

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Overview

Super simple worked example of swapping users. This function block requies parameters of the known username and password. This could be used as an alternative to Logout when you need to logout to a base "minimal" user level.

Example of quick user switching.

(function (TcHmi) {

    var LoginUser = function (UserName,Password,StayLoggedIn,ReloadPage) {

        if (TcHmi.Server.isWebsocketReady()) {
            var request = {
                "requestType": "ReadWrite",
                "commands": [
                    {
                        "commandOptions": ["SendErrorMessage", "SendWriteValue"],
                        "symbol": "Login",
                        "writeValue":
                        {
                            "userName": UserName,
                            "password": Password,
                            "persistent": StayLoggedIn
                        }
                    }
                ]
            };

            // Send request to TwinCAT HMI Server.
            TcHmi.Server.request(request, function (data) {
                // Callback handling.
                if (data.error !== TcHmi.Errors.NONE) {
                    // Handle TcHmi.Server class level error here.
                    return;
                }
                var response = data.response;
                if (response.error !== undefined) {
                    // Handle TwinCAT HMI Server response level error here.
                    return;
                }
                var commands = response.commands;
                if (commands === undefined) {
                    return;
                }
                for (var i = 0, ii = commands.length; i < ii; i++) {
                    var command = response.commands[i];
                    if (command === undefined) {
                        return;
                    }
                    if (command.error !== undefined) {
                        // Handle TwinCAT HMI Server command level error here.
                        return;
                    }
                    // Handle result...
                    if (command.symbol = "Login") {

                        if (StayLoggedIn) {
                            // Remember the current session for 30 days
                            document.cookie = "sessionId=" + command.readValue + ";path=/;max-age=" + 60 * 60 * 24 * 30;
                        } else {
                            // Reset max-age
                            document.cookie = "sessionId=" + command.readValue + ";path=/";
                        }

                        if (ReloadPage) {
                            // login was successful, load base url
                            if (window.location.href.indexOf("Login") != -1) {
                                window.location.href = window.location.href.replace(/Login.*?\//, '');
                            }
                            else {
                                window.location.reload();
                            }
                        }
                    }
                }
            });
        }
    };
    
    TcHmi.Functions.registerFunction('LoginUser', LoginUser);
})(TcHmi);

Install

Not required. Simply open the project.

TwinCAT

This project uses TcXaeShell 3.1.4024.10 and TwinCAT HMI 1.10.1336.404

Getting started

This is not a guide for TcXaeShell, please visit http://beckhoff.com/ for further guides