Search and download AUR packages

aur.js

#!/usr/bin/node

/* -----------------------------------------------------------------------------
 * aur.js
 * Search and download AUR packages
 * Author: Franck Marcia - https://github.com/fmarcia
 */

"use strict";

var https = require("https");

/* -----------------------------------------------------------------------------
 * check <query> as 1st argument
 */

(function main() {

    var query = process.argv[2];

    if (!query) {
        return exit(-1, "syntax: aur <package>");
    }

    // next step
    search(query);

}());

/* -----------------------------------------------------------------------------
 * search for <query> in aur packages
 */

function search(query) {

    var data = "";

    https.get(
        "https://aur.archlinux.org/rpc.php?type=search&arg=" + query,
        function (response) {
            response.setEncoding("utf8");
            // accumulate data
            response.on("data", function (chunk) { data += chunk; });
            // next step
            response.on("end", function () { check(query, data); });
        }

    ).on(
        "error",
        function (error) {
            exit(-2, "list error: " + error.message);
        }
    );
}

/* -----------------------------------------------------------------------------
 * check response
 */

function check(query, data) {

    var pkgs;

    try {
        pkgs = JSON.parse(data);
    } catch (e) {
        pkgs = {};
    }

    if (!pkgs.type || !pkgs.results) {
        return exit(-3, "invalid response");
    }

    if (pkgs.type === "error") {
        return exit(-4, pkgs.results);
    }

    if (!pkgs.results.length) {
        console.log("no package for " + query);
        return;
    }

    // next
    sort(pkgs);
}

/* -----------------------------------------------------------------------------
 * sort packages list by NumVotes descending then PackageBase ascending
 */

function sort(pkgs) {

    pkgs.results.sort(function (a, b) {
        if (a.NumVotes > b.NumVotes) return -1;
        if (a.NumVotes < b.NumVotes) return 1;
        if (a.NumVotes === b.NumVotes) {
            if (a.PackageBase < b.PackageBase) return -1;
            if (a.PackageBase > b.PackageBase) return 1;
            return 0;
        }
    });

    // next step
    list(pkgs);
}

/* -----------------------------------------------------------------------------
 * print out packages list
 */

function list(pkgs) {

    var length = pkgs.results.length;

    console.log(length + " package" + (length > 1 ? "s" : "") + " found");

    pkgs.results.forEach(function (pkg, index) {
        console.log(
            (index + 1) + ". " +
            pkg.PackageBase + " " + pkg.Version +
            " (" + pkg.NumVotes + ")"
        );
    });

    // next step
    choose(pkgs);
}

/* -----------------------------------------------------------------------------
 * choose a package (or quit)
 */

function choose(pkgs) {

    var inter = require("readline").createInterface({
        input: process.stdin,
        output: process.stdout
    });

    inter.setPrompt(" > ");
    inter.prompt();

    inter.on("line", function (answer) {
        answer = parseInt(answer, 10) - 1;
        if (pkgs.results[answer]) {
            // next step
            download(pkgs.results[answer]);
        }
        inter.close();
    });
}

/* -----------------------------------------------------------------------------
 * download a package
 */

function download(pkg) {

    var url = "https://aur.archlinux.org" + pkg.URLPath;
    var file = url.split("/").pop();
    var stream = require("fs").createWriteStream(file);

    https.get(
        url,
        function (response) {
            response.on("data", function (chunk) { stream.write(chunk); });
            response.on("end", function () { stream.end(); });
        }

    ).on(
        "error",
        function (error) {
            exit(-5, "download error: " + error.message);
        }
    );
}

/* -----------------------------------------------------------------------------
 * exit on error
 */

function exit(exitCode, message) {
    console.error(message);
    process.exit(exitCode);
}