initerest and random merge posts

dbTools/profile.js

@@ -51,10 +51,10 @@ userDB = (DB) => {
     DB.getPopularProfiles = async (limit = 10) => {
         return DB.profileCols.aggregate([
             {
-                $match: {isGroup: false}
+                $match: {isGroup: {$ne: true}}
             },
             {
-                $addFields: { subscribed_count: {$size: { "$ifNull": [ {"$objectToArray" : "$subscribed"}, [] ] } } }
+                $addFields: { subscribed_count: {$size: { "$ifNull": [ "$following", [] ] } } }
             },
             {   
                 $sort: {"subscribed_count":-1} 
@@ -64,7 +64,7 @@ userDB = (DB) => {
             }
         ]).limit(limit).toArray().catch((err) => {
             console.log(err);
-            return false;
+            return [];
         });
     }
 
@@ -84,7 +84,33 @@ userDB = (DB) => {
             }
         ]).limit(limit).toArray().catch((err) => {
             console.log(err);
-            return false;
+            return [];
+        });
+    }
+
+    DB.getFriendsFriends = async (profileId) => {
+        const profile = await DB.getProfile(profileId);
+        if(!profile) return [];
+        let ids = profile.following.map((id)=>DB.ObjectID(id));
+        let alreadyFollowingMap = {};
+        alreadyFollowingMap[profileId] = 1; //skip that profile
+        profile.following.forEach(id => {
+            if(!alreadyFollowingMap[id]) alreadyFollowingMap[id] = 1;
+        })
+        return DB.profileCols.find({_id:{$in: ids}}).project({following: 1}).toArray().then(profiles => {
+            let friendsOfFriendsMap = {};
+            profiles.forEach(p => {
+                p.following.forEach(followingId => {
+                    if(alreadyFollowingMap[followingId]) return 0;
+                    if(!friendsOfFriendsMap[followingId]) friendsOfFriendsMap[followingId] = 0;
+                    friendsOfFriendsMap[followingId] = friendsOfFriendsMap[followingId] + 1;
+                });
+            });
+            // sort by most related?
+            return Object.keys(friendsOfFriendsMap);
+        }).catch((err) => {
+            console.log(err);
+            return [];
         });
     }
 

routes/post.js

@@ -16,24 +16,65 @@ DB.getDB.then((DB) => {
         return post.profileid === profileid;
     };
 
-    router.get("/", async (req, res) => {
-        const profileid = getProfileId(req);
-        let posts = await DB.getFeed(profileid);
-        //Add non-organic posts
+    const generateNonOrganicPosts = async (req, profileid) => {
+        let posts = [];
+        // Popular Profiles
         const popularProfiles = await DB.getPopularProfiles(5);
-        let content = "Popular users to follow:\n";
+        let content = "Active users to follow:\n";
         popularProfiles.forEach((p)=>{
             content += "@p:" + p._id + "\n";
         });
         let popularProfilesPost = new Post({profileid: 1, content, nonOrganicType: "PopularUsers"});
+        posts.push(popularProfilesPost);
+
+        // Popular Groups
         const popularGroups = await DB.getPopularGroups(5);
-        content = "Popular users to follow:\n";
+        content = "Popular groups to follow:\n";
         popularGroups.forEach((p)=>{
             content += "@p:" + p._id + "\n";
         });
         let popularGroupsPost = new Post({profileid: 1, content, nonOrganicType: "PopularGroups"});
-        posts.push(popularProfilesPost);
         posts.push(popularGroupsPost);
+
+        const yourFollowsInterests = await DB.getFriendsFriends(profileid);
+        content = "People your follow has these interests:\n";
+        yourFollowsInterests.forEach((p)=>{
+            content += "@p:" + p + "\n";
+        });
+        let yourFollowsInterestsPost = new Post({profileid: 1, content, nonOrganicType: "PopularUsers"});
+        posts.push(yourFollowsInterestsPost);
+
+        return posts;
+    };
+
+    const mergePosts = (organic, nonOrganic) => {
+        if(!organic || organic.length < 5) return nonOrganic;
+        //organic.push(...nonOrganic);
+        let mergedPosts = [];
+        while(organic.length + nonOrganic.length){
+            if(organic.length == 0){
+                mergedPosts.push(nonOrganic.shift());
+                continue;
+            }
+            if(nonOrganic.length == 0){
+                mergedPosts.push(organic.shift());
+                continue;
+            }
+            if(Math.random() < 0.2){
+                mergedPosts.push(nonOrganic.shift());
+            } else {
+                mergedPosts.push(organic.shift());
+            }
+        }
+        return mergedPosts;
+    };
+
+    router.get("/", async (req, res) => {
+        const profileid = getProfileId(req);
+        let organicPosts = await DB.getFeed(profileid);
+        //Add non-organic posts
+        const nonOrganicPosts = await generateNonOrganicPosts(req, profileid);
+        const posts = mergePosts(organicPosts, nonOrganicPosts);
         return res.json(posts);
     });