template-wip.js

const
    async = require('async'),
    SocialNetworkService = require('SocialNetworkService'),
    Rabbitmq = require('rabbitmq-boilerplate'),
    configStorage = require('needToMake');

class Template {
    constructor() {
        //define variables
        this.config = {
            accountQueue: "template_task-account",
            postQueue: "template_task-post",
            storePostQueue: "template_store-post",
            storeCommentQueue: "template_store-comment"
        }
        this.snsConnect = null;
        this.rabbitConnect = null;

        //prepair and start
        this.prepair()
            .then(() => this.start())
            .catch((err) => console.error(err))
    }

    prepair() {
        const snsPromise = new Promise((resolve, reject) => {
            configStorage.watch("template/token", (token) => {
                if (this.snsConnect) {
                    this.snsConnect.disconnect();
                }
                const sns = new SocialNetworkService(token);
                sns.connect((err, conn) => {
                    if (err) {
                        return reject(err)
                    }
                    this.snsConnect = conn;
                    resolve();
                });
            });
        });

        const rabbitmqPromise = new Promise((resolve) => {
            configStorage.watch("global/rabbitmq", (connString) => {
                if (!this.rabbitConnect) {
                    this.rabbitConnect = new Rabbitmq();
                }
                this.rabbitConnect.config(connString);
                resolve();
            });
        });

        return Promise.all([snsPromise, rabbitmqPromise]);
    }

    start() { //class entry point
        this.listenAccount();
        this.listenPost();
    }

    listenAccount() {
        this.rabbitConnect.listen(this.config.accountQueue, (err, msg) => {
            if (err) {
                console.error(err);
                return process.nextTick(() => this.listenAccount());
            }

            const task = JSON.parse(msg.payload);

            async.autoInject({
                account: (cb) => {
                    this.snsConnect.findAccount(task.userId, cb);
                },
                posts: (account, cb) => {
                    this.snsConnect.getPosts(account, cb);
                }
            }, (err, scope) => {
                if (err) {
                    msg.resolve();
                    return console.error(err);
                }
                async.eachSeries(scope.posts, (post, cb) => {
                    async.parallel([
                        (cb) => {
                            this.rabbitConnect.send(post, this.config.storePostQueue, cb);
                        },
                        (cb) => {
                            this.rabbitConnect.send(post, this.config.storeCommentQueue, cb);
                        }
                    ], cb)

                }, (err) => {
                    err && console.error(err);
                    msg.resolve();
                })
            });
        })
    }

    listenPost() {
        this.rabbitConnect.listen(this.config.postQueue, (err, msg) => {
            if (err) {
                console.error(err);
                return process.nextTick(() => this.listenPost());
            }

            const task = JSON.parse(msg.payload);

            async.autoInject({
                account: (cb) => {
                    this.snsConnect.findAccount(task.userId, cb);
                },
                post: (account, cb) => {
                    this.snsConnect.openPost(account, task.postId, cb);
                },
                comments: (post, cb) => {
                    this.snsConnect.getComments(post, cb);
                }
            }, (err, scope) => {
                if (err) {
                    msg.resolve();
                    return console.error(err);
                }
                async.until(() => !scope.comments.length, (cb) => {
                    const batch = scope.comments.splice(0, 20);
                    this.rabbitConnect.send(batch, this.config.storeCommentQueue, cb);
                }, (err) => {
                    err && console.error(err);
                    msg.resolve();
                })
            });
        })
    }
}

module.exports = new Template();