superstatic/lib/activator.js

A static file server for fancy apps

"use strict";
/**
 * Copyright (c) 2022 Google LLC
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
const middleware = require("./middleware");
const _ = require("lodash");
const promiseback = require("./utils/promiseback");
const Activator = function (spec, provider) {
    this.spec = spec;
    this.provider = provider;
    this.stack = this.buildStack();
    if (_.isFunction(spec.config)) {
        this.awaitConfig = spec.config;
    }
    else {
        this.awaitConfig = function () {
            return Promise.resolve(spec.config);
        };
    }
};
Activator.prototype.buildStack = function () {
    const self = this;
    const stack = this.spec.stack.slice(0);
    _.forEach(this.spec.before, (wares, name) => {
        stack.splice(...[stack.indexOf(name), 0].concat(wares));
    });
    _.forEach(this.spec.after, (wares, name) => {
        stack.splice(...[stack.indexOf(name) + 1, 0].concat(wares));
    });
    return stack.map((ware) => {
        return _.isFunction(ware) ? ware : middleware[ware](self.spec);
    });
};
Activator.prototype.build = function () {
    const self = this;
    return function (req, res, next) {
        promiseback(self.awaitConfig, 2)(req, res).then((config) => {
            req.superstatic = config || {};
            const stack = self.stack.slice(0).reverse();
            const _run = function () {
                if (!stack.length) {
                    return next();
                }
                const fn = stack.pop();
                return fn(req, res, _run);
            };
            _run();
        }, next);
    };
};
module.exports = function (spec, provider) {
    return new Activator(spec, provider).build();
};