Plain Reddit reader for the console with Node.js

redditer.js

// esversion: 6;

/// SETTINGS ///
// Maximum number of posts to be showed
const MAX_COUNT = 10;
// List of the subreddits, the desired sort order (multiple is allowed)
// and count of posts
const SUBREDDITS = [
    {
        name: 'spacex',
        action: ['new'],
        count: MAX_COUNT
    },
    {
        name: 'europe',
        action: ['top'],
        count: MAX_COUNT
    }
];
/// END OF SETTINGS ///

/// ... BLA BLA CODE ... ///
const https = require('https');
const colors = require('colors');

const HOST = "https://www.reddit.com";
const URI = "/r/$S/$A.json";
const ERROR_INVALID_POST = -3;
const ERROR_BAD_ACTION = -2;
const ERROR_INVALID_DATA = -1;

class SubReddit {
    constructor(name) {
        this.name = name || "all";
    }

    isValidAction(action) {
        const ACTIONS = ['new', 'top', 'hot', 'controversial', 'rising'];
        return ACTIONS.includes(action);
    }

    fetchTopPosts(count) { return this.fetchPosts('top', count); }
    fetchNew(count) { return this.fetchPosts('new', count); }
    fetchHotPosts(count) { return this.fetchPosts('hot', count); }

    getURI(action) {
        return URI.replace('$S', this.name)
            .replace('$A', action || 'new');
    }

    getURL(action) {
        return HOST + this.getURI(action);
    }

    fetchPosts(action, count) {
        if (this.isValidAction(action)) {
            return this._fetchPosts(this.getURL(action || 'top'), count);
        } else {
            return Promise.reject([ERROR_BAD_ACTION, "Bad action"]);
        }
    }
    
    _fetchPosts(requestURL, count) {
        // console.log("Fetching: ", requestURL);
        return new Promise((resolve, reject) => {
            count = count || MAX_COUNT;

            https.get(requestURL, (r) => {
                const { statusCode } = r;

                if (statusCode !== 200) {
                    reject([statusCode, `Houston, we have problem! (status code ${statusCode})`]);
                    return;
                }

                r.setEncoding('utf-8');
                let rawData = '';
                r.on('data', (chunk) => { rawData += chunk; });
                r.on('end', () => {
                    const listing = JSON.parse(rawData);
                    if (!listing || !listing.data || !listing.data.children) {
                        reject([ERROR_INVALID_DATA, `Houston, we have problem! (status code ${statusCode})`]);
                        return;
                    }
                    const jsonPosts = listing.data.children;
                    let posts = [];

                    for (let i = 0; i < count; i++) {
                        let jsonPost = jsonPosts[i];
                        if (!jsonPost || !jsonPost.data || !jsonPost.data.title || !jsonPost.data.url) {
                            reject([ERROR_INVALID_POST, `Houston, we have a main bus A undervolt! (invalid post data)`]);
                            return;
                        }

                        posts.push(new Post(jsonPosts[i].data.title, jsonPosts[i].data.url));
                    }
                    resolve(posts);
                });
            });
        });
    }
}

class Post {
    constructor(title, url) {
        this.title = title || null;
        this.url = url || null;
    }

    prettyPrint() {
        console.log(this.toPrettyString());
    }

    toPrettyString() {
        return ` ${this.title.green.bold}\n\t\t${this.url.blue.underline}\n`;
    }
}

/// MAIN ///

SUBREDDITS.forEach((sub) => {
    const { name, count, action } = sub;
    let sr = new SubReddit(name);
    action.forEach((act) => {
        sr.fetchPosts(act, count)
            .then((posts) => {
                console.log(colors.cyan.bold(`Showing ${count} posts for r/${name}, sorted by '${act}'\n`));
                posts.forEach((post) => {
                    post.prettyPrint();
                });
            })
            .catch((error) => {
                console.error(colors.red("Error: " + error[1]));
            });
    });
});
/// QED ///