RocketChat/Rocket.Chat

import { Logger } from '@rocket.chat/logger';

const logger = new Logger('TemplateVarHandler');

export const templateVarHandler = function (variable: string, object: Record<string, any>): string | undefined {
    const templateRegex = /#{([\w\-]+)}/gi;
    let match = templateRegex.exec(variable);
    let tmpVariable = variable;

    if (match == null) {
        if (!object.hasOwnProperty(variable)) {
            logger?.debug(`user does not have attribute: ${variable}`);
            return;
        }
        return object[variable];
    }
    logger?.debug('template found. replacing values');
    while (match != null) {
        const tmplVar = match[0];
        const tmplAttrName = match[1];

        if (!object.hasOwnProperty(tmplAttrName)) {
            logger?.debug(`user does not have attribute: ${tmplAttrName}`);
            return;
        }

        const attrVal = object[tmplAttrName];
        logger?.debug(`replacing template var: ${tmplVar} with value: ${attrVal}`);
        tmpVariable = tmpVariable.replace(tmplVar, attrVal);
        match = templateRegex.exec(variable);
    }
    return tmpVariable;
};