Rename some methods and centralize db instantiation

index.js

@@ -1,4 +1,5 @@
 const axios     = require('axios').default
+const Database  = require('better-sqlite3')
 const cheerio   = require('cheerio')
 const flatten   = require('lodash.flatten')
 const RSSParser = require('rss-parser')
@@ -8,9 +9,13 @@ const ucfirst   = require('ucfirst')
 const luxon     = require('luxon')
 const DateTime  = luxon.DateTime
 
-const parser = new RSSParser()
+function db(options={}) {
+  const dbPath = process.env.DSS_DB || './main.db'
+  return new Database(dbPath, options)
+}
 
-async function getFeed(feedURL='https://dailystormer.su/feed/') {
+async function fetchFeed(feedURL='https://dailystormer.su/feed/') {
+  const parser = new RSSParser()
   const res = await axios.get(feedURL)
   const feed = await parser.parseString(res.data)
   return feed
@@ -21,8 +26,8 @@ async function getFeed(feedURL='https://dailystormer.su/feed/') {
  * @param {String} feedURL - URL of the feed
  * @returns {Object} parsed RSS feed
  */
-async function getArticlesFromFeed(feedURL='https://dailystormer.su/feed/') {
-  const feed = await getFeed(feedURL);
+async function fetchArticlesFromFeed(feedURL='https://dailystormer.su/feed/') {
+  const feed = await fetchFeed(feedURL);
   return feed.items.map((a) => {
     const slug = url.parse(a.link).pathname
     const article = {
@@ -45,12 +50,13 @@ async function scanCategory(baseURL, category, options={}) {
   // scan first page of category to find out how many pages we have.
   const res = await axios.get(categoryURL)
   const $ = cheerio.load(res.data)
-  const p = parseInt($('.pagination .pages').text().split(/\s/)[3])
+  let p
+  p = (options.pages) ? options.pages : parseInt($('.pagination .pages').text().split(/\s/)[3])
   const pages = []
   for (let i = 1; i <= p; i++) {
     pages.push(i)
   }
-  const scans = await Bluebird.map(pages, (n) => { return scanCategoryPage(baseURL, category, n) }, { concurrency: 4 })
+  const scans = await Bluebird.map(pages, (n) => { return scanCategoryPage(baseURL, category, n) }, { concurrency: 8 })
   const flatScans = flatten(scans)
   return flatScans
 }
@@ -103,7 +109,7 @@ async function articleExists(db, slug) {
 }
 
 // TODO rename to fetchArticle
-async function getArticle(url) {
+async function fetchArticle(url) {
   const res = await axios.get(url)
   const $ = cheerio.load(res.data)
   const $article = $('article')
@@ -378,15 +384,51 @@ async function countArticlesByCategory(db, name) {
 
 // SECTION: Tags
 
+async function getArticlesByTag(db, name, limit, offset) {
+  const articles = db.prepare(`
+    SELECT a.slug, a.title, a.author, a.published_date
+    FROM article a
+    JOIN article__tag ac ON a.id = ac.article_id
+    JOIN tag c ON c.id = ac.tag_id
+    WHERE c.name = @name
+    ORDER BY published_date DESC
+    LIMIT @limit
+    OFFSET @offset
+  `).all({ name, limit, offset })
+  const articlesWithMonth = articles.map((art) => {
+    const d = DateTime.fromISO(art.published_date).setZone('UTC')
+    art.month = d.toFormat('MMMM y')
+    return art
+  })
+  return articlesWithMonth
+}
+
+async function countArticlesByTag(db, name) {
+  const count = db.prepare(`
+    SELECT count(*) AS c
+    FROM article a
+    JOIN article__tag at ON a.id = at.article_id
+    JOIN tag c ON c.id = at.tag_id
+    WHERE c.name = @name
+  `).get({ name }) 
+  return count.c
+}
+
+async function countTags(db) {
+  const count = db.prepare(`SELECT count(*) c FROM tag`).get()
+  return count.c
+}
+
 module.exports = {
-  getFeed,
-  getArticlesFromFeed,
+  db,
+  fetchFeed,
+  fetchArticlesFromFeed,
   scanCategory,
   scanCategoryPage,
   unhyphen,
   extractTaxonomyFromArticle,
   articleExists,
-  getArticle,
+  fetchArticle,
   getCategory,
   getTag,
   assocCategory,