build.js

#!/usr/bin/env node

"use strict";

const build_conf = {
    protected_dirs: ["assets", "style", "articles"],
};

const fs = require("fs");
const browserify = require("browserify");
const curDir = process.cwd();

// Handle home page
const b = browserify();
b.add(`${curDir}/src/main.js`)
    .bundle()
    .pipe(fs.createWriteStream(`${curDir}/public/main.js`));

// Handle subpages
function getPageHtml(pageName, pageMeta) {
    let html = fs.readFileSync(`${curDir}/public/index.html`, "utf-8");
    const setMeta = function (metaName, value) {
        return html.replace(
            html.match(new RegExp(`<meta.+name="${metaName}".+>`, "g")),
            `<meta name="${metaName}" content="${value}"/>`
        );
    };
    const setTitle = function (value) {
        return html.replace(
            html.match(new RegExp(`<title.+</title>`, "g")),
            `<title>${value}</title>`
        );
    };
    const setStyleSheet = function () {
        return html.replace(
            html.match(new RegExp(`<link.+/style.css>`, "g")),
            `<link href="/style/style.css" rel="stylesheet" />`
        );
    };
    const setJs = function () {
        return html.replace(
            html.match(new RegExp(`<script.+main.js.+</script>`, "g")),
            `<script type="text/javascript" src="./${pageName}.js"></script>`
        );
    };
    const setAdditionalMeta = function (metas) {
        return html.replace(
            "</head>",
            `${metas
                .map(kv => {
                    const [name, content] = kv;
                    return `<meta name="${name}" content="${content}"/>`;
                })
                .join("\n")}</head>`
        );
    };
    html = setMeta("description", pageMeta.description);
    html = setTitle(pageMeta.title);
    html = setStyleSheet();
    html = setJs();
    html = setAdditionalMeta(
        Object.entries(pageMeta).filter(kv => kv[0] !== "description" && kv[0] !== "title")
    );

    return html;
}

const pages = fs.readdirSync(`${curDir}/src/pages`);

for (const p of pages) {
    const fPath = `${curDir}/src/pages/${p}`;
    const targetDirPath = `${curDir}/public/${p}`;

    if (!fs.existsSync(targetDirPath)) {
        fs.mkdirSync(targetDirPath);
    }

    const b = browserify();

    b.add(fPath)
        .bundle()
        .pipe(fs.createWriteStream(`${targetDirPath}/${p}.js`));

    const page = fs.createWriteStream(`${targetDirPath}/index.html`);
    const pageMeta = JSON.parse(fs.readFileSync(`${fPath}/meta.json`, "utf-8"));
    page.write(getPageHtml(p, pageMeta));
}

// If pages have been deleted in source, remove them in output directory too.
for (const dir of fs.readdirSync(`${curDir}/public`).filter(f => {
    if (build_conf.protected_dirs.includes(f)) return false;
    const stats = fs.statSync(`${curDir}/public/${f}`);
    return stats.isDirectory();
})) {
    if (!pages.includes(dir)) {
        const dPath = `${curDir}/public/${dir}`;
        try {
            const nestedFiles = fs.readdirSync(dPath);
            for (const nf of nestedFiles) {
                fs.unlinkSync(`${dPath}/${nf}`);
            }
            fs.rmdirSync(dPath);
        } catch (error) {
            console.error(error);
        }
    }
}