wgdown/dist/src/child.js

Node 真·多线程下载。A tool of multi-process downloading for node

"use strict";
/**
 * wgdown ts
 *
 * wgdown is a download tool using child process
 *
 * @author wind2esg
 * @date 20191008
 *
 * #child
 *
 * result
 * '0' init
 * '1' local exists
 * '2' not exist in server
 * '3' download but problem
 * '0' downloaded
 * '5' error
 */
Object.defineProperty(exports, "__esModule", { value: true });
const fs = require("fs");
const process = require("process");
const request = require("request");
new Promise((resolve, reject) => {
    let msg = {};
    msg.serverPath = process.argv[2];
    msg.localPath = process.argv[3];
    msg.size = 0;
    msg.result = '0';
    if (fs.existsSync(msg.localPath)) {
        msg.result = '1';
        process.send(JSON.stringify(msg));
        resolve();
        return;
    }
    let rs = request(msg.serverPath);
    rs.on('error', (err) => {
        console.log("error:  " + msg.serverPath + "   " + err);
        msg.result = '5';
        process.send(JSON.stringify(msg));
        resolve();
        return;
    })
        .on('response', (response) => {
        if (response.statusCode == 200) {
            msg.size = parseInt(response.headers["content-length"]);
            let ws = fs.createWriteStream(msg.localPath);
            rs.pipe(ws.on('error', (err) => {
                console.log(msg.localPath);
                console.log(err);
                ws.end();
                msg.result = '5';
                process.send(JSON.stringify(msg));
                resolve();
                return;
            })
                .on('finish', () => {
                if (msg.size > ws.bytesWritten) {
                    ws.end();
                    msg.result = '3';
                    process.send(JSON.stringify(msg));
                    resolve();
                    return;
                }
                ws.end();
                process.send(JSON.stringify(msg));
                resolve();
                return;
            }));
        }
        else {
            msg.result = '2';
            process.send(JSON.stringify(msg));
            resolve();
            return;
        }
    });
});