tm-apps-list-api/src/topStories.js

"use strict";

let R = require("ramda");
let hl = require("highland");
let utils = require("./utils");
const BeneLogger = require('bene-logger');
const requestCB = require('./request');

const getByPubId = (tableName, db) => hl.wrapCallback((id, cb) => {
    db.query({
        "TableName": tableName,
        "KeyConditionExpression": 'Id = :hkey',
        "ExpressionAttributeValues": {
            ':hkey': id
        },
        "Limit": 40
    }, cb);
});

module.exports = (config, db) => (req, res, next) => {

    const source = req.params.source;

    const publicationId = req.params.publicationId;
    const logger = new BeneLogger({logging: config.logging.enabled});

    logger.setDefaults({
        body: JSON.stringify(req.params),
        service_name: 'appsTopStoriesAPI'
    });

    logger.info('Pools GET request');

    const articlesEndpoint = !req.query.cache || req.query.cache !== "false" ? config.cacheEndpoint : config.articleEndpoint;

    const stream = getByPubId(config.dynamodb.tableName, db)(`${source}.${publicationId}`)
        .pluck("Items")
        .reject(R.isEmpty)
        .sequence()
        .pluck("ArticleId");
    
    const GetArticle = utils.makeArticleRequestCB(config, logger, articlesEndpoint, source, publicationId);
    const NotFound = utils.notFound(`No pools found for publication /${source}/${publicationId}`);

    if(requestCB(config).circuitBreaker.isOpen()) {
        res.header('etag', req.header.etag);
        res.send(304);
    } else {
        utils.getArticlesInParallel(logger, GetArticle, NotFound, stream)
            .map(utils.addMeta)
            .toCallback(utils.sendResponse(logger, res, next));
    }
};