add fallback parser when LD/JSON not found, use DOM parser

lib/parser-utils.js

@@ -0,0 +1,32 @@
+const dayjs = require('dayjs')
+
+// NOTE: Specific formatting for `ics` library
+const parseDates = (startDate, endDate) => {
+  const start = startDate ? [
+    startDate.year(),
+    startDate.month() + 1,
+    startDate.date(),
+    startDate.hour(),
+    startDate.minute(),
+  ] : (() => {
+    const now = dayjs()
+
+    return [
+      now.year(),
+      now.month() + 1,
+      now.date()
+    ]
+  })()
+  const diffInMinutes = endDate ?
+    endDate.diff(startDate, 'minutes') :
+    120
+
+  const duration = { minutes: diffInMinutes }
+
+  return {
+    start,
+    duration,
+  }
+}
+
+module.exports = { parseDates }

lib/services/dom-parser.js

@@ -0,0 +1,77 @@
+const cheerio = require('cheerio')
+const dayjs = require('dayjs')
+const { parseDates } = require('../parser-utils')
+
+const parseDate = (timeText) => {
+  const parts = timeText.split('at')
+  const datePart = parts[0] || null
+  const timePart = parts[1] || null
+
+  if (!datePart) {
+    return {
+      start: null,
+      duration: null,
+    }
+  }
+
+  const normalizedTimeString = `${datePart}${timePart || ''}`
+  const startTime = dayjs(normalizedTimeString)
+
+  const { start, duration } = parseDates(startTime, null)
+
+  return {
+    start,
+    duration,
+  }
+}
+
+const createLocationData = (streetText, areaText) => {
+  const location = ([ streetText, areaText ])
+    .filter(i => i)
+    .join(', ') || ''
+
+  return location.replace(/\r?\n|\r/g, ' ')
+}
+
+// NOTE: Fallback parser
+// Attempt reading event data directly from DOM
+const parseUsingDOM = (html, url) => {
+  console.info('Fallback parser used')
+  const $ = cheerio.load(html)
+  const title = $('title').text()
+
+  const $eventSummary = $('#event_summary')
+  const $eventNode = $eventSummary ? $eventSummary.children()[1] : null
+
+  const $timeNode = $eventNode ? $eventNode.childNodes[0] : null
+  const $locationNode = $eventNode ? $eventNode.childNodes[1] : null
+
+  const timeText = $timeNode ? $timeNode.attribs.title : ''
+
+  const $locationBlock = $locationNode ? $($locationNode).find('td') : null
+  const $locationBlockTDs = $locationBlock ? $locationBlock.children() : []
+  const $streetBlock = $locationBlockTDs[1] || null
+  const $areaBlock = $locationBlockTDs[2] || null
+
+  const streetText = $streetBlock ? $($streetBlock).text() : ''
+  const areaText = $areaBlock ? $($areaBlock).text() : ''
+
+  const location = createLocationData(streetText, areaText)
+  const { start, duration } = parseDate(timeText)
+
+  const eventData = {
+    location,
+    start,
+    duration,
+    title,
+    url,
+  }
+
+  if (!eventData.title || !eventData.start) {
+    return null
+  }
+
+  return eventData
+}
+
+module.exports = parseUsingDOM

lib/services/ics-retriever.js

@@ -1,13 +1,21 @@
 const crawl = require('./crawler')
-const parseHTML = require('./parser')
+const parseUsingLDJSONData = require('./ldjson-parser')
+const parseUsingDOM = require('./dom-parser')
 const generateICS = require('./ics-generator')
-const { getNormalizedUrl } = require('../utils')
+const { createParserError, getNormalizedUrl } = require('../utils')
 
 const retrieveICS = async (URLparameter) => {
   try {
     const url = getNormalizedUrl(URLparameter)
     const html = await crawl(url)
-    const eventData = parseHTML(html)
+    const LDJSONEventData = parseUsingLDJSONData(html)
+    const eventData = LDJSONEventData || parseUsingDOM(html, url)
+
+    if (!eventData) {
+      throw createParserError()
+      return
+    }
+
     const icsFile = await generateICS(eventData)
     return icsFile
   } catch (err) {

lib/services/ldjson-parser.js

@@ -1,35 +1,6 @@
-const dayjs = require('dayjs')
 const cheerio = require('cheerio')
-const { createParserError } = require('../utils')
-
-// NOTE: Specific formatting for `ics` library
-const parseDates = (startDate, endDate) => {
-  const start = startDate ? [
-    startDate.year(),
-    startDate.month() + 1,
-    startDate.date(),
-    startDate.hour(),
-    startDate.minute(),
-  ] : (() => {
-    const now = dayjs()
-
-    return [
-      now.year(),
-      now.month() + 1,
-      now.date()
-    ]
-  })()
-  const diffInMinutes = endDate ?
-    endDate.diff(startDate, 'minutes') :
-    120
-
-  const duration = { minutes: diffInMinutes }
-
-  return {
-    start,
-    duration,
-  }
-}
+const dayjs = require('dayjs')
+const { parseDates } = require('../parser-utils')
 
 const parseEventData = (eventData) => {
   const startDate = eventData.startDate && dayjs(eventData.startDate)
@@ -60,7 +31,7 @@ const parseEventData = (eventData) => {
   }
 }
 
-const parseHTML = (html) => {
+const parseUsingLDJSONData = (html) => {
   try {
     // NOTE: Mobile web should have serialized
     // event info in one of the script tags
@@ -81,7 +52,7 @@ const parseHTML = (html) => {
     }, null)
 
     if (!rawData) {
-      throw createParserError()
+    return null
     }
 
     const eventData = JSON.parse(rawData.slice(12, -5))
@@ -93,4 +64,4 @@ const parseHTML = (html) => {
   }
 }
 
-module.exports = parseHTML
+module.exports = parseUsingLDJSONData

lib/utils.js

@@ -1,3 +1,5 @@
+const dayjs = require('dayjs')
+
 const checkValidURL = (url) => {
   return checkURLFormat(url) ||
     checkNumberURLParameter(url)