feat(editCommentHistory): add feature to get edit history for a comment

- Created feature to get edit history of a comment.
  GET /api/articles/<slug>/comment/<comment-id>/history
  * Authorization required
  * Admin priviledge required
- Wrote tests
[Finishes #164608984]

server/controllers/articleComment.js

@@ -197,6 +197,53 @@ class Comment {
       return response(res).serverError({ errors: { server: ['database error'] } });
     }
   }
+
+  /**
+   * @description returns edit history of a particular comment.
+   * @param {*} req The request object
+   * @param {*} res The response object
+   * @returns {undefined}
+   */
+  static async getEditHistory(req, res) {
+    const { commentId } = req.params;
+    const { article } = req;
+
+    const comment = await ArticleComment.findOne({
+      where: {
+        articleId: article.id, // This ensures the comment belongs to the specified article
+        id: commentId
+      },
+      attributes: ['comment', 'createdAt']
+    });
+    if (!comment) {
+      return response(res).notFound('Comment does not exists');
+    }
+
+    // Get comment history
+    const dbHistory = await CommentEditHistory.findAll({
+      where: {
+        commentId,
+      },
+      attributes: [['previousComment', 'comment'], 'createdAt'],
+      order: [
+        ['id', 'DESC']
+      ]
+    });
+
+    let original, history;
+    if (dbHistory.length === 0) {
+      original = comment;
+      history = [];
+    } else {
+      original = dbHistory.pop();
+      history = dbHistory;
+      history.unshift(comment);
+    }
+    response(res).success({
+      original,
+      history
+    });
+  }
 }
 
 export default Comment;

server/routes/articles.js

@@ -79,4 +79,10 @@ router.delete('/articles/:slug/comment/:commentId',
   ValidateComment.validateComment,
   Comment.deleteComment);
 
+router.get('/articles/:slug/comment/:commentId/history',
+  AuthenticateUser.verifyUser,
+  AuthenticateUser.isAdmin,
+  AuthenticateArticle.verifyArticle,
+  Comment.getEditHistory);
+
 export default router;

server/test/commentEditHistory.spec.js

@@ -0,0 +1,133 @@
+import chai, { expect } from 'chai';
+import chaiHttp from 'chai-http';
+import dotenv from 'dotenv';
+import app from '../app';
+
+dotenv.config();
+chai.use(chaiHttp);
+
+let userToken, adminToken, commentId;
+const articleSlug = 'this-is-an-article-1';
+
+describe('Test endpoint to return edit history', () => {
+  before('it should get admin user', (done) => {
+    chai
+      .request(app)
+      .post('/api/users/login')
+      .send({
+        name: process.env.SUPER_ADMIN_USERNAME,
+        password: process.env.SUPER_ADMIN_PASSWORD
+      })
+      .end((err, res) => {
+        expect(res.status).to.equal(200);
+        const { token } = res.body.user;
+        adminToken = token;
+        done();
+      });
+  });
+
+  before('it should create a regular user', (done) => {
+    chai
+      .request(app)
+      .post('/api/users')
+      .send({
+        firstname: 'Comment',
+        lastname: 'Bot',
+        username: 'commentbot',
+        email: 'commentbot@authorshaven.com',
+        password: '1234567890'
+      })
+      .end((err, res) => {
+        expect(res.status).to.equal(201);
+        const { token } = res.body.user;
+        userToken = token;
+        done();
+      });
+  });
+
+  it('should create a new comment', (done) => {
+    chai
+      .request(app)
+      .post(`/api/articles/${articleSlug}/comment`)
+      .set('authorization', `Bearer ${userToken}`)
+      .send({
+        comment: 'This is original comment'
+      })
+      .end((err, res) => {
+        expect(res.status).to.equal(201);
+        const { userComment } = res.body;
+        commentId = userComment.id;
+        done();
+      });
+  });
+
+  it('should edit the above comment', (done) => {
+    chai
+      .request(app)
+      .patch(`/api/articles/${articleSlug}/comment/${commentId}`)
+      .set('authorization', `Bearer ${userToken}`)
+      .send({
+        comment: 'This is the edited version of the comment'
+      })
+      .end((err, res) => {
+        expect(res.status).to.equal(200);
+        done();
+      });
+  });
+
+  it('should edit the above comment again', (done) => {
+    chai
+      .request(app)
+      .patch(`/api/articles/${articleSlug}/comment/${commentId}`)
+      .set('authorization', `Bearer ${userToken}`)
+      .send({
+        comment: 'This is the second time the comment is editted'
+      })
+      .end((err, res) => {
+        expect(res.status).to.equal(200);
+        done();
+      });
+  });
+
+  it('should return a 401 if user trying to get edit history is not an admin', (done) => {
+    chai
+      .request(app)
+      .get(`/api/articles/${articleSlug}/comment/${commentId}/history`)
+      .set('authorization', `bearer ${userToken}`)
+      .end((err, res) => {
+        expect(res.status).to.equal(401);
+        done();
+      });
+  });
+
+  it('should return a 404 admin is trying to get history for a comment that does not exists', (done) => {
+    chai
+      .request(app)
+      .get(`/api/articles/${articleSlug}/comment/9876545/history`)
+      .set('authorization', `Bearer ${adminToken}`)
+      .end((err, res) => {
+        expect(res.status).to.equal(404);
+        done();
+      });
+  });
+
+  it('should get a edit history of the comment of the article', (done) => {
+    chai
+      .request(app)
+      .get(`/api/articles/${articleSlug}/comment/${commentId}/history`)
+      .set('authorization', `bearer ${adminToken}`)
+      .end((err, res) => {
+        expect(res.status).to.equal(200);
+
+        const { original, history } = res.body;
+        expect(original.comment).to.be.a('string');
+        expect(history).to.be.an('array');
+        expect(history.length).to.equal(2);
+        expect(original.comment).to.equal('This is original comment');
+        // History is sorted starting from most recent editted.
+        expect(history[0].comment).to.equal('This is the second time the comment is editted');
+        expect(history[1].comment).to.equal('This is the edited version of the comment');
+        done();
+      });
+  });
+});

server/test/index.js

@@ -9,3 +9,4 @@ import './report.spec';
 import './articleSearch.spec';
 import './admin.spec';
 import './notification.spec';
+import './commentEditHistory.spec';