ayakashi/lib/domQL/walking.js

The next generation web scraping framework

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.tagWalk = exports.domWalk = void 0;
const query_1 = require("./query");
function domWalk(env, query, scope) {
    let results = [];
    const limit = query.limit || Number.MAX_SAFE_INTEGER;
    const skip = query.skip || 0;
    let passCounter = 0;
    let addedCounter = 0;
    function _domWalk(node, callback) {
        if (callback(node) === false)
            return false;
        let currentNode = (node && node.firstChild) || null;
        while (currentNode != null) {
            if (_domWalk(currentNode, callback) === false)
                return false;
            currentNode = currentNode.nextSibling;
        }
        return true;
    }
    if (query.order === "desc") {
        _domWalk(scope, el => {
            if (el === scope)
                return;
            if (el && el.nodeName === "#text")
                return;
            if (!query.where) {
                results.push(el);
            }
            else {
                if (query_1.runQuery(env, query, el) === true) {
                    results.push(el);
                }
            }
        });
        results.reverse();
        results = results.splice(skip, limit);
    }
    else {
        _domWalk(scope, el => {
            if (el === scope)
                return;
            if (el && el.nodeName === "#text")
                return;
            let hasMatch = false;
            if (!query.where) {
                hasMatch = true;
            }
            else {
                hasMatch = query_1.runQuery(env, query, el);
            }
            if (hasMatch === true) {
                passCounter += 1;
                if (passCounter > skip && addedCounter < limit) {
                    results.push(el);
                    addedCounter += 1;
                }
            }
        });
    }
    return results;
}
exports.domWalk = domWalk;
function tagWalk(env, query, scope) {
    const results = [];
    const limit = query.limit || Number.MAX_SAFE_INTEGER;
    const skip = query.skip || 0;
    let passCounter = 0;
    let addedCounter = 0;
    const tags = Array.from(scope.getElementsByTagName("*"));
    if (query.order === "desc") {
        tags.reverse().forEach(el => {
            if (el === scope)
                return;
            if (el && el.nodeName === "#text")
                return;
            let hasMatch = false;
            if (!query.where) {
                hasMatch = true;
            }
            else {
                hasMatch = query_1.runQuery(env, query, el);
            }
            if (hasMatch === true) {
                passCounter += 1;
                if (passCounter > skip && addedCounter < limit) {
                    results.push(el);
                    addedCounter += 1;
                }
            }
        });
    }
    else {
        tags.forEach(el => {
            if (el === scope)
                return;
            if (el && el.nodeName === "#text")
                return;
            let hasMatch = false;
            if (!query.where) {
                hasMatch = true;
            }
            else {
                hasMatch = query_1.runQuery(env, query, el);
            }
            if (hasMatch === true) {
                passCounter += 1;
                if (passCounter > skip && addedCounter < limit) {
                    results.push(el);
                    addedCounter += 1;
                }
            }
        });
    }
    return results;
}
exports.tagWalk = tagWalk;