serve gitlab artifacts via http

app.js

"use strict";
const express = require('express');
const gitlab = require('gitlab');
const Zip = require('jszip');
const got = require('got');
const mimeType = require('mime-types');

const glClient = gitlab({url: 'https://my.cool.gitlab.instance.io', token: 'YOUR_TOKEN_HERE'});
const app = express();

let zipCache = {};
function getZipServer(project_web_url, build_id) {
    let key = project_web_url + ':' + build_id;
    if (!zipCache[key]) {
        let url = project_web_url + '/builds/' + build_id + '/artifacts/download?private_token=YOUR_TOKEN_HERE';
        zipCache[key] = got(url, {encoding: null})
            .then(response => new Zip(response.body))
    }

    return zipCache[key];
}

let buildCache = {};
function getBuildInformation(project_name, build_id) {
    let key = project_name + ":" + build_id;
    if (!buildCache[key]) {
        buildCache[key] = new Promise(resolve => {
            glClient.projects.search(project_name, projects => {
                let project = projects[0];
                glClient.projects.builds.showBuild(project.id, build_id,
                    build => resolve({project, build})
                );
            })
        })
    }

    return buildCache[key]
}

app.get('/project/:project_name/:build_id/*', (req, res) => {
    let build_id = req.params.build_id;
    let project_name = req.params.project_name;
    let localUrl = req.params[0];

    getBuildInformation(project_name, build_id)
        .then(info => getZipServer(info.project.web_url, info.build.id))
        .then(archive => {
            let file = archive.file(localUrl);
            let folder = archive.folder(localUrl);
            if (file) {
                res.append('Content-Type', mimeType.lookup(localUrl));
                res.append('Cache-Control', 'public, max-age=31557600000');
                archive.file(localUrl).async("nodebuffer").then(buffer => res.send(buffer));
            } else if (folder) {
                let content = folder.file(/.*/)
                    .map(file => file.name.replace(new RegExp('^' +localUrl), ''))
                    .map(filename => '<li><a href="' + filename + '">' + filename + '</a></li>').join('');
                res.send('<ul>' + content + '</ul>');
            } else {
                res.status(404).end();
            }
        })
        .catch(err => console.error(err));
});

app.listen(8080);

package.json

{
  "name": "museum",
  "version": "1.0.0",
  "description": "",
  "main": "app.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "Mark Schmale <[email protected]>",
  "license": "ISC",
  "dependencies": {
    "express": "^4.14.0",
    "gitlab": "^1.7.1",
    "got": "^6.3.0",
    "jszip": "^3.1.2",
  }
}