liking and quoting work

functions/handlers/post.js

@@ -1,5 +1,7 @@
 /* eslint-disable promise/always-return */
 const admin = require('firebase-admin');
+const { db } = require('../util/admin');
+
 exports.putPost = (req, res) => {
 
     const newPost = {
@@ -27,6 +29,106 @@ exports.putPost = (req, res) => {
     });
 };
 
+
+exports.getPost = (req, res) => {
+    let postData = {};
+    db.doc(`/posts/${req.params.postId}`)
+    .get()
+    .then((doc) => {
+        if (!doc.exists) {
+            return res.status(404).json({error: 'Post is not found'});
+
+        }
+        postData = doc.data();
+        postData.postId = doc.id;
+        return res.status(200).json(postData);
+    })
+    .catch((err) => {
+        console.error(err); 
+        return res.status(500).json({error: 'Something is wrong'});
+    })
+}
+
+exports.likePost = (req, res) => {
+    let postData;
+    const likeDoc = admin.firestore().collection('likes').where('userHandle', '==', req.userData.handle)
+    .where('postId', '==', req.params.postId).limit(1);
+
+    const postDoc = db.doc(`/posts/${req.params.postId}`);
+
+    likeDoc.get()
+    .then((data) => {
+        if (data.empty) {
+            return admin.firestore().collection('likes').add({
+                postId : req.params.postId,
+                userHandle: req.userData.handle
+            })
+            .then(() => {
+                postData.likeCount++;
+                return postDoc.update({likeCount : postData.likeCount})
+            })
+            .then(() => {
+                return res.status(200).json(postData);
+            })
+        }
+        else {
+            return res.status(400).json({error: 'Post has already been liked.'})
+        }
+    })
+    .catch((err) => {
+        console.error(err);
+        return res.status(500).json({error: 'Something is wrong'});
+    })
+
+}
+
+exports.unlikePost = (re, res) => {
+
+    let postData;
+    const likeDoc = admin.firestore().collection('likes').where('userHandle', '==', req.userData.handle)
+    .where('postId', '==', req.params.postId).limit(1);
+
+    const postDoc = db.doc(`/posts/${req.params.postId}`);
+
+    likeDoc.get()
+    .then((data) => {
+        if (data.empty) {
+            return res.status(400).json({ error: 'Post cannot be unliked because it is not liked at the moment.' });
+          } else {
+            return db
+              .doc(`/likes/${data.docs[0].id}`)
+              .delete()
+              .then(() => {
+                postData.likeCount--;
+                return postDoc.update({ likeCount: postData.likeCount });
+              })
+              .then(() => {
+                res.status(200).json(postData);
+              });
+          }
+    })
+    .catch((err) => {
+        console.error(err);
+        return res.status(500).json({error: 'Something is wrong'});
+    })
+
+}
+
+exports.getallPostsforFeed = (req, res) => {
+    admin.firestore().collection('posts').get()
+    .then((data) => {
+        let posts = [];
+        data.forEach(function(doc) {
+            posts.push(doc.data());
+        });
+        return res.status(200).json(posts);
+    })
+    .catch((err) => {
+        console.error(err);
+        return res.status(500).json({error: 'Failed to fetch all posts written by all other users.'})
+    })
+};
+
 exports.getallPostsforUser = (req, res) => {
     admin.firestore().collection('posts').where('userHandle', '==', req.userData.handle ).get()
     .then((data) => {