rework for ui nofitications (#4630, #4615)

scripts/lua/modules/notifications/notifications_manager.lua

@@ -0,0 +1,98 @@
+--
+-- (C) 2020 - ntop.org
+--
+
+local dirs = ntop.getDirs()
+package.path = dirs.installdir .. "/scripts/lua/modules/?.lua;" .. package.path
+package.path = dirs.installdir .. "/scripts/lua/modules/alert_notifications/?.lua;" .. package.path
+
+local page_utils = require("page_utils")
+local template = require("template_utils")
+local defined_notifications = require("defined_notifications")
+
+-- Redis Key used to store the notification status
+local REDIS_KEY = "ntopng.user.%s.dismissised_notices.notification_%s"
+local notifications_manager = {}
+
+local function notification_has_been_dismissed(notification_id)
+    return ntop.getPref(string.format(REDIS_KEY, _SESSION['user'], notification_id)) == "1"
+end
+
+--- Returns an array of notification to be displayed inside the pages
+--- @return table
+function notifications_manager.load_main_notifications()
+
+    local container = {}
+    local current_page = page_utils.get_active_entry()
+    local curent_subpage = _GET['page']
+
+    for _, notification in ipairs(defined_notifications) do
+
+        -- if the current page is excluded then don't show the notification
+        if (table.contains(notification.excluded_pages, current_page)) then
+            goto continue
+        end
+
+        -- if we are in a excluded subpage then don't show the notification
+        local excluded_subpages = notification.excluded_subpages or {[current_page] = {}}
+        if (table.contains(excluded_subpages, curent_subpage)) then
+            goto continue
+        end
+
+        -- check if the notification have the predicate function
+        if (notification.predicate == nil) then
+            traceError(TRACE_ERROR, TRACE_CONSOLE, "The notification '".. notification.id .. "' doesn't have a predicate function!")
+            goto continue
+        end
+
+        -- has the notification be dissmissed by the user?
+        local dismissed = (notification.dismissable and notification_has_been_dismissed(notification.id))
+        if (dismissed) then goto continue end
+
+        -- check if we can add the notification inside the page
+        local subpages = notification.subpages or {[current_page] = {}}
+        local can_add = (table.len(notification.pages) == 0) or (
+            table.contains(notification.pages, current_page)) or (table.contains(subpages, curent_subpage))
+
+        if can_add then
+            -- check the predicate function
+            notification.predicate(notification, container)
+        end
+
+        -- used to jump to the next notification
+        ::continue::
+    end
+
+    return container
+end
+
+--- Dismiss the notification if the notification is is valid, otherwise return an error
+--- @param notification_id string The notification to dismiss
+--- @return (boolean, string) True if the notification has been dismissed
+function notifications_manager.dismiss_notification(notification_id)
+
+    -- Check if the notification id is valid in order to prevent to set not valid
+    -- REDIS keys
+    local compare = (function(n) return n.id == notification_id end)
+    if not (table.contains(defined_notifications, notification_id, compare)) then
+        traceError(TRACE_ERROR, TRACE_CONSOLE, "The passed notification ID is not valid!")
+        return false, "Not a valid notification ID!"
+    end
+
+    -- Dismiss the notification
+    ntop.setPref(string.format(REDIS_KEY, _SESSION['user'], notification_id), "1")
+    return true, "Success"
+end
+
+--- Create a notification container inside the page where to render the alert notifications.
+--- @param container_id string The container id attribute
+--- @param notifications table A alert_notifications list to render inside the container,
+function notifications_manager.render_notifications(container_id, notifications)
+    -- render the notifications
+    print(template.gen('pages/components/notification_container.template', {
+        notifications = notifications,
+        container_id = container_id
+    }))
+end
+
+return notifications_manager