@xpresser/params-loader/index.js

Xpresser's url params to state Loader.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.ParamsMiddleware = void 0;
/**
 * Params Loader function.
 * @param params
 */
function generateParamLoader(params) {
    /**
     * Load Param Middleware Generator.
     * @param param
     */
    return function ParamLoader(param) {
        // If param has no definition, throw error.
        if (!params[param])
            throw new Error(`Definition for param: '${String(param)}' not found!`);
        // Get params definition as `helper`
        const helper = params[param];
        // Convert to express
        return async (http) => {
            // Get value of param from http
            const value = http.params[param];
            // run not found if param is missing
            if (helper.notFound && !value)
                return helper.notFound(http, value);
            // Get loadedValue of param from loader
            let loadedValue = undefined;
            try {
                // if loaded exists, run loader else use value
                if (helper.load) {
                    loadedValue = await helper.load(value, http);
                }
                else {
                    loadedValue = value;
                }
                // Stop if headers are already sent
                if (http.res.headersSent)
                    return;
            }
            catch (e) {
                if (helper.loadError)
                    return helper.loadError(http, e);
                // log errors
                http.$("logError")(e);
            }
            // if not loadedValue run notFound
            if (helper.notFound && !loadedValue)
                return helper.notFound(http, value);
            // add to boot if addToBoot is true
            if (helper.addToBoot)
                http.addToBoot(helper.as || param, loadedValue);
            // Add to loadedParams state
            http.addLoadedParam(helper.as || param, loadedValue);
            // return next
            return http.next();
        };
    };
}
/**
 * Generate Middleware from defined params.
 * @param params
 */
function ParamsMiddleware(params) {
    // Generate param loader.
    const loadParam = generateParamLoader(params);
    // Holds all middlewares.
    const middleware = {};
    // Populate middleware.
    for (const param in params) {
        middleware[param] = loadParam(param);
    }
    return middleware;
}
exports.ParamsMiddleware = ParamsMiddleware;