Use new user scripts config and gui

The user scripts configuration can now be configured from the "User Scripts" entry under the cog
icon. It allows the creation of multiple configuration presets to be applied to hosts, networks and
interfaces.

attic/scripts/lua/modules/user_scripts.lua

@@ -0,0 +1,182 @@
+-- ##############################################
+
+-- @brief Get the default configuration for the given user script
+-- and granularity.
+-- @param user_script a user_script returned by user_scripts.load
+-- @param granularity_str the target granularity
+-- @return a table with the default configuration
+function user_scripts.getDefaultConfig(user_script, granularity_str)
+   local conf = {script_conf = {}, enabled = user_script.default_enabled}
+
+  if((user_script.default_values ~= nil) and (user_script.default_values[granularity_str] ~= nil)) then
+    -- granularity specific default
+    conf.script_conf = user_script.default_values[granularity_str] or {}
+  else
+    conf.script_conf = user_script.default_value or {}
+  end
+
+  return(conf)
+end
+
+-- ##############################################
+
+local function getConfigurationKey(subdir)
+   -- NOTE: strings needed by user_scripts.deleteConfigurations
+   -- NOTE: The configuration must not be saved under a specific ifid, since we
+   -- allow global interfaces configurations
+   return(string.format("ntopng.prefs.user_scripts.conf.%s", subdir))
+end
+
+-- ##############################################
+
+-- Get the user scripts configuration
+-- @param subdir: the subdir
+-- @return a table
+-- {[hook] = {entity_value -> {enabled=true, script_conf = {a = 1}, }, ..., default -> {enabled=false, script_conf = {}, }}, ...}
+-- @note debug with: redis-cli get ntopng.prefs.user_scripts.conf.interface | python -m json.tool
+local function loadConfiguration(subdir)
+   local key = getConfigurationKey(subdir)
+   local value = ntop.getPref(key)
+
+   if(not isEmptyString(value)) then
+      value = json.decode(value) or {}
+   else
+      value = {}
+   end
+
+   return(value)
+end
+
+-- ##############################################
+
+-- Save the user scripts configuration.
+-- @param subdir: the subdir
+-- @param config: the configuration to save
+local function saveConfiguration(subdir, config)
+   local key = getConfigurationKey(subdir)
+
+   if(table.empty(config)) then
+      ntop.delCache(key)
+   else
+      local value = json.encode(config)
+      ntop.setPref(key, value)
+   end
+
+   -- Reload the periodic scripts as the configuration has changed
+   ntop.reloadPeriodicScripts()
+end
+
+-- ##############################################
+
+function user_scripts.deleteConfigurations()
+   deleteCachePattern(getConfigurationKey("*"))
+end
+
+-- ##############################################
+
+-- This needs to be called whenever the available_modules.conf changes
+-- It updates the single scripts config
+local function reload_scripts_config(available_modules)
+   local scripts_conf = available_modules.conf
+
+   for _, script in pairs(available_modules.modules) do
+      script.conf = scripts_conf[script.key] or {}
+   end
+end
+
+-- ##############################################
+
+local function delete_script_conf(scripts_conf, key, hook, conf_key)
+   if(scripts_conf[key] and scripts_conf[key][hook]) then
+      scripts_conf[key][hook][conf_key] = nil
+
+      -- Cleanup empty tables
+      if table.empty(scripts_conf[key][hook]) then
+	 scripts_conf[key][hook] = nil
+
+	 if table.empty(scripts_conf[key]) then
+	    scripts_conf[key] = nil
+	 end
+      end
+   end
+end
+
+
+-- ##############################################
+
+function user_scripts.handlePOST(subdir, available_modules, hook, entity_value, remote_host)
+   if(table.empty(_POST)) then
+      return
+   end
+
+   hook = hook or NON_TRAFFIC_ELEMENT_CONF_KEY
+   entity_value = entity_value or NON_TRAFFIC_ELEMENT_ENTITY
+
+   local scripts_conf = available_modules.conf
+
+   for _, user_script in pairs(available_modules.modules) do
+      -- There are 3 different configurations:
+      --  - specific_config: the configuration specific of an host/interface/network
+      --  - global_config: the configuration specific for all the (local/remote) hosts, interfaces, networks
+      --  - default_config: the default configuration, specified by the user script
+      -- They follow the follwing priorities:
+      -- 	[lower] specific_config > global_config > default [upper]
+      --
+      -- Moreover:
+      --   - specific_config is only set if it differs from the global_config
+      --   - global_config is only set if it differs from the default_config
+      --
+
+      -- This is used to represent the previous config in order of priority in order
+      -- to determine if the current config differs from its default.
+      local upper_config = user_scripts.getDefaultConfig(user_script, hook)
+
+      -- NOTE: we must process the global_config before the specific_config
+      for _, prefix in ipairs({"global_", ""}) do
+	 local k = prefix .. user_script.key
+	 local is_global = (prefix == "global_")
+	 local enabled_k = "enabled_" .. k
+	 local is_enabled = _POST[enabled_k]
+	 local conf_key = ternary(is_global, get_global_conf_key(remote_host), entity_value)
+	 local script_conf = nil
+
+	 if(user_script.gui and (user_script.gui.post_handler ~= nil)) then
+	    script_conf = user_script.gui.post_handler(k)
+	 end
+
+	 if(is_enabled == nil) then
+	    -- TODO remove this after changing the gui to support a separate on/off field
+	    -- For backward compatibility, an empty configuration means that the script is disabled
+
+	    if(user_script.gui and (user_script.gui.post_handler ~= nil) and (subdir ~= "flow")) then
+	       is_enabled = not table.empty(script_conf)
+	    else
+	       is_enabled = user_script.default_enabled
+	    end
+	 else
+	    is_enabled = (is_enabled == "on")
+	 end
+
+	 local cur_config = {
+	    enabled = is_enabled,
+	    script_conf = script_conf,
+	 }
+
+	 if(not table.compare(upper_config, cur_config)) then
+	    -- Configuration differs
+	    scripts_conf[user_script.key] = scripts_conf[user_script.key] or {}
+	    scripts_conf[user_script.key][hook] = scripts_conf[user_script.key][hook] or {}
+	    scripts_conf[user_script.key][hook][conf_key] = cur_config
+	 else
+	    -- Use the default
+	    delete_script_conf(scripts_conf, user_script.key, hook, conf_key)
+	 end
+
+	 -- Needed for specific_config vs global_config comparison
+	 upper_config = cur_config
+      end
+   end
+
+   reload_scripts_config(available_modules)
+   saveConfiguration(subdir, scripts_conf)
+end