website-scraper/node-website-scraper

import ImgSrcsetTag from '../path-containers/html-img-srcset-tag.js';
import CommonTag from '../path-containers/html-common-tag.js';
import CssText from '../path-containers/css-text.js';

const pathContainersByRule = [
    { selector: '[style]', attr: 'style', containerClass: CssText },
    { selector: 'style', containerClass: CssText },
    { selector: '*[srcset]', attr: 'srcset', containerClass: ImgSrcsetTag }
];

/**
 * Represents pair of cheerio element and rule to find text with children resources
 */
class HtmlSourceElement {
    /**
     * @param {Object} el - cheerio obj for dom element
     * @param {Object} rule - rule used to find current element
     * @param {string} rule.selector - cheerio selector
     * @param {string} rule.attr - attribute to find text which contains resources. if not set - use inner html
     */
    constructor (el, rule) {
        this.el = el;
        this.rule = rule;
    }

    /**
     * Get resource data from element using rule
     * @returns {string}
     */
    getData () {
        return this.rule.attr ? this.el.attr(this.rule.attr) : this.el.html();
    }

    /**
     * Update attribute or inner text of el with new data
     * @param {string} newData
     */
    setData (newData) {
        this.rule.attr ? this.el.attr(this.rule.attr, newData) : this.el.html(newData);
    }

    removeIntegrityCheck () {
        if (this.el.attr('integrity')) {
            this.el.attr('integrity', null);
        }
    }

    /**
     * Returns PathContainer instance for element
     * @returns {CssText|HtmlCommonTag|HtmlImgSrcSetTag|null}
     */
    getPathContainer () {
        const selectedRule = this.findMatchedRule(pathContainersByRule);
        const ContainerClass = selectedRule ? selectedRule.containerClass : CommonTag;
        const textWithResources = this.getData();
        return textWithResources ? new ContainerClass(textWithResources) : null;
    }

    matchesRule (rule) {
        return this.el.is(rule.selector) && this.rule.attr === rule.attr;
    }

    findMatchedRule (rulesArray) {
        return rulesArray.find(this.matchesRule, this);
    }

    toString () {
        return JSON.stringify({selector: this.rule.selector, attr: this.rule.attr, data: this.getData()});
    }
}

export default HtmlSourceElement;