fix: fix broken answers feed

this commit fixes the issue of answers not being shown as the underlying HTML changed which broke
old scraping logic

BREAKING CHANGE: older versions will not work with answer route

fix https://github.com/zyachel/quetre/issues/96

fetchers/answersFetcher.js

@@ -0,0 +1,76 @@
+/* eslint-disable no-useless-catch */
+////////////////////////////////////////////////////////
+//                      IMPORTS
+////////////////////////////////////////////////////////
+import * as cheerio from 'cheerio';
+import getAxiosInstance from '../utils/getAxiosInstance.js';
+import AppError from '../utils/AppError.js';
+
+////////////////////////////////////////////////////////
+//                     FUNCTION
+////////////////////////////////////////////////////////
+/**
+ * makes a call to quora.com(with the resourceStr appended) and returns parsed JSON containing the data about the resource requested.
+ * @param {string} resourceStr a string after the baseURL
+ * @param {string} lang additional options
+ * @returns JSON containing the result
+ */
+const answersFetcher = async (resourceStr, lang) => {
+  try {
+    const axiosInstance = getAxiosInstance(lang);
+    const res = await axiosInstance.get(encodeURIComponent(resourceStr));
+    const $ = cheerio.load(res.data);
+
+    const rawData = { question: null, answers: [], related: [], answerCount: 0 };
+
+    // there are about 9-10 script tags containing data we need
+    $('body script').each((i, el) => {
+      const text = $(el).html();
+      const matches = text.match(/\.push\((".*")\);/); // data is contained like: someProp.push("<data>");
+
+      if (!matches) return;
+
+      // brittle logic, but works
+      const matchedPart = JSON.parse(JSON.parse(matches[1])).data;
+
+      // only question block has this word
+      if (typeof matchedPart.question?.viewerHasAnswered !== 'undefined') {
+        rawData.question = matchedPart.question;
+
+        // primary answer block
+      } else if (matchedPart.question?.answers?.edges) {
+        rawData.answers.push(matchedPart.question.answers.edges[0].node.answer);
+
+        // other answer blocks
+      } else if (
+        // eslint-disable-next-line no-underscore-dangle
+        matchedPart.node?.__typename === 'QuestionRelevantAnswerItem2'
+      ) {
+        rawData.answers.push(matchedPart.node.answer);
+
+        // related questions block contains both answer count and related questions
+      } else if (matchedPart.bottomRelatedQuestionsInfo) {
+        rawData.related = matchedPart.bottomRelatedQuestionsInfo.relatedQuestions;
+        rawData.answerCount = matchedPart.answerCount;
+      }
+    });
+
+    if (!rawData.question) throw new AppError("couldn't retrieve data", 500);
+
+    return rawData;
+  } catch (err) {
+    const statusCode = err.response?.status;
+    if (statusCode === 404) throw new AppError('Not found', 404);
+    else if (statusCode === 429 || statusCode === 403)
+      throw new AppError(
+        'Quora is rate limiting this instance. Try another or host your own.',
+        503
+      );
+    else throw err;
+  }
+};
+
+////////////////////////////////////////////////////////
+//                     EXPORTS
+////////////////////////////////////////////////////////
+export default answersFetcher;

fetchers/getAnswers.js

@@ -1,87 +1,69 @@
 ////////////////////////////////////////////////////////
 //                     IMPORTS
 ////////////////////////////////////////////////////////
-// import log from '../utils/log.js';
-import AppError from '../utils/AppError.js';
 import { quetrefy } from '../utils/urlModifiers.js';
-import fetcher from './fetcher.js';
+import answersFetcher from './answersFetcher.js';
 
 ////////////////////////////////////////////////////////
 //                     FUNCTION
 ////////////////////////////////////////////////////////
-const KEYWORD = 'question';
-
 const getAnswers = async (slug, lang) => {
   // getting data and destructuring it in case it exists
-  const res = await fetcher(slug, { keyword: KEYWORD, lang });
+  const rawData = await answersFetcher(slug, lang);
-
-  const {
-    data: { [KEYWORD]: rawData },
-  } = JSON.parse(res);
-
-  if (!rawData)
-    throw new AppError(
-      "Answers couldn't be fetched. Recheck the URL, or resend the request if you believe the URL is correct.",
-      404
-    );
 
   // array containing all the answers with metadata
-  const ansArr = rawData.pagedListDataConnection.edges
+  const ansArr = rawData.answers.map(answer => ({
-    .filter(ansObj => ansObj.node.answer !== undefined)
+    text: JSON.parse(answer.content).sections,
-    .map(ansObj => ({
+    isViewable: !!answer.viewerHasAccess,
-      text: JSON.parse(ansObj.node.answer.content).sections,
+    creationTime: answer.creationTime,
-      isViewable: !!ansObj.node.answer.viewerHasAccess,
+    updatedTime: answer.updatedTime,
-      creationTime: ansObj.node.answer.creationTime,
+    numComments: answer.numDisplayComments,
-      updatedTime: ansObj.node.answer.updatedTime,
+    numUpvotes: answer.numUpvotes,
-      numComments: ansObj.node.answer.numDisplayComments,
+    numViews: answer.numViews,
-      numUpvotes: ansObj.node.answer.numUpvotes,
+    numShares: answer.numShares,
-      numViews: ansObj.node.answer.numViews,
+    numAnswerRequests: answer.numRequesters,
-      numShares: ansObj.node.answer.numSharers,
+    aid: answer.aid,
-      numAnswerRequests: ansObj.node.answer.numRequesters,
+    isBusinessAnswer: answer.businessAnswer,
-      aid: ansObj.node.answer.aid,
-      isBusinessAnswer: ansObj.node.answer.businessAnswer,
     author: {
-        uid: ansObj.node.answer.author.uid,
+      uid: answer.author.uid,
-        isAnon: ansObj.node.answer.author.isAnon,
+      isAnon: answer.author.isAnon,
-        image: ansObj.node.answer.author.profileImageUrl,
+      image: answer.author.profileImageUrl,
-        isVerified: ansObj.node.answer.author.isVerified,
+      isVerified: answer.author.isVerified,
-        url: quetrefy(ansObj.node.answer.author.profileUrl),
+      url: quetrefy(answer.author.profileUrl),
-        name: `${ansObj.node.answer.author.names[0].givenName} ${ansObj.node.answer.author.names[0].familyName}`,
+      name: `${answer.author.names[0].givenName} ${answer.author.names[0].familyName}`,
-        credential: ansObj.node.answer.authorCredential?.translatedString,
+      credential: answer.authorCredential?.translatedString,
-        // additionalCredentials: ansObj.node.answer?.credibilityFacts.map(),
+      // additionalCredentials: answer.node.answer?.credibilityFacts.map(),
     },
     originalQuestion: {
-        text: JSON.parse(ansObj.node.answer.question.title).sections,
+      text: JSON.parse(answer.question.title).sections,
-        url: quetrefy(ansObj.node.answer.question.url),
+      url: quetrefy(answer.question.url),
-        qid: ansObj.node.answer.question.qid,
+      qid: answer.question.qid,
-        isDeleted: ansObj.node.answer.question.isDeleted,
+      isDeleted: answer.question.isDeleted,
     },
   }));
 
   // main data object to be returned
   const data = {
     question: {
-      text: JSON.parse(rawData.title).sections,
+      text: JSON.parse(rawData.question.title).sections,
-      url: quetrefy(rawData.url),
+      url: quetrefy(rawData.question.url),
-      qid: rawData.qid,
+      qid: rawData.question.qid,
-      idDeleted: rawData.isDeleted,
+      idDeleted: rawData.question.isDeleted,
-      isViewable: rawData.isVisibleToViewer,
+      isViewable: rawData.question.isVisibleToViewer,
-      askerUid: rawData.asker.uid,
+      askerUid: rawData.question.asker.uid,
     },
     numAnswers: rawData.answerCount,
     answers: ansArr,
-    topics: rawData.topics.map(topicObj => ({
+    topics: rawData.question.topics.map(topicObj => ({
       tid: topicObj.tid,
       name: topicObj.name,
       url: quetrefy(topicObj.url),
     })),
-    relatedQuestions: rawData.bottomRelatedQuestionsInfo.relatedQuestions.map(
+    relatedQuestions: rawData.related.map(questionObj => ({
-      questionObj => ({
       qid: questionObj.qid,
       url: quetrefy(questionObj.url),
       text: JSON.parse(questionObj.title).sections,
-      })
+    })),
-    ),
   };
 
   return data;