reworked blog notifications

now the notification are stored in redis and not anymore in browser local storage

scripts/lua/modules/blog_utils.lua

@@ -6,12 +6,83 @@ local json = require("dkjson")
 
 local blog_utils = {}
 
+function intersect_posts(s1, s2)
+
+    local newSet = {}
+    local post1 = s1[1]
+
+    -- if there aren't any old post then return the new ones
+    if (s1[1] == nil) then
+        for _, p in ipairs(s2) do
+            p.users = {}
+            for username, _ in pairs(ntop.getUsers()) do
+                p["users"][username] = {}
+                p["users"][username]["isNew"] = true
+            end
+        end
+        return s2
+    end
+    -- if there aren't any new post then return the old ones
+    if (s2[1] == nil) then
+        return s1
+    end
+
+    for i = 1, 3 do
+
+        local post2 = s2[i]
+
+        if (post1.epoch < post2.epoch) then
+            newSet[i] = post2
+            newSet[i + 1] = s1[i]
+            newSet[i]["users"] = {}
+            for username, _ in pairs(ntop.getUsers()) do
+                newSet[i]["users"][username] = {}
+                newSet[i]["users"][username]["isNew"] = true
+            end
+        elseif (post1.epoch == post2.epoch) then
+            newSet[i + 1] = s1[i]
+        end
+    end
+
+    return newSet
+end
+
+function blog_utils.updatePostState(blogNotificationId, username)
+
+    local postsJSON = ntop.getPref("ntopng.prefs.blog_feed")
+    local posts = json.decode(postsJSON)
+    local success = false
+
+    for _, p in ipairs(posts) do
+        if p.id == blogNotificationId then
+            p.users[username].isNew = false
+            success = true
+        end
+    end
+
+    ntop.setPref("ntopng.prefs.blog_feed", json.encode(posts))
+
+    return (success)
+end
+
 function blog_utils.updateRedis(newPosts)
+
+    -- decode older posts from updateRedis
+    local oldPostsJSON = ntop.getPref("ntopng.prefs.blog_feed")
+    local oldPosts = {}
+    if (not isEmptyString(oldPostsJSON)) then
+        oldPosts = json.decode(oldPostsJSON)
+    end
+
+    -- intersect two notifications sets and marks the new
+    local intersected = intersect_posts(oldPosts, newPosts)
     -- save the posts inside redis
-    ntop.setPref("ntopng.notifications.blog_feed", json.encode(newPosts))
+    ntop.setPref("ntopng.prefs.blog_feed", json.encode(intersected))
+
 end
 
 function blog_utils.fetchLatestPosts()
+
     local JSON_FEED = "https://www.ntop.org/blog/feed/json"
     local response = ntop.httpGet(JSON_FEED)
 
@@ -62,8 +133,9 @@ function blog_utils.fetchLatestPosts()
     return(true)
 end
 
-function blog_utils.readPostsFromRedis()
-    local postsJSON = ntop.getPref("ntopng.notifications.blog_feed")
+function blog_utils.readPostsFromRedis(username)
+
+    local postsJSON = ntop.getPref("ntopng.prefs.blog_feed")
     local posts = nil
 
     if not isEmptyString(postsJSON) then
@@ -74,6 +146,11 @@ function blog_utils.readPostsFromRedis()
         posts = {}
     end
 
+    -- normalize the post data
+    for i, p in pairs(posts) do
+        p.isNew = p.users[username].isNew
+    end
+
     return posts
 end