Rework system probes (now called system scripts)

scripts/lua/modules/system_scripts_utils.lua

@@ -0,0 +1,169 @@
+--
+-- (C) 2013-19 - ntop.org
+--
+
+local system_scripts = {}
+
+local dirs = ntop.getDirs()
+package.path = dirs.installdir .. "/scripts/lua/modules/?.lua;" .. package.path
+package.path = dirs.installdir .. "/scripts/lua/modules/timeseries/?.lua;" .. package.path
+
+local os_utils = require("os_utils")
+local ts_utils = require("ts_utils_core")
+
+local system_scripts_dir = dirs.installdir .. "/scripts/callbacks/system"
+local task_to_periodicity = {
+  ["second"] = 1,
+  ["minute"] = 60,
+  ["5min"]   = 300,
+  ["hourly"] = 3600,
+  ["daily"]  = 86400,
+}
+
+-- ##############################################
+
+function system_scripts.getSystemProbes(task)
+  local base_dir = system_scripts_dir .. "/" .. task
+  local probes = pairsByKeys(ntop.readdir(base_dir)) or {}
+
+  return function()
+    local get_next = true
+
+    while get_next do
+      local probe_script = probes()
+      get_next = false
+
+      if(probe_script ~= nil) and (string.ends(probe_script, ".lua")) then
+        local name = string.sub(probe_script, 1, string.len(probe_script)-4)
+        local path = os_utils.fixPath(base_dir .. "/" .. probe_script)
+        local _module = loadfile(path)()
+
+        if _module == nil then
+          traceError(TRACE_ERROR, TRACE_CONSOLE, string.format("Could not load module '%s'", path))
+          get_next = true
+        elseif _module.isActive() then
+          return name, _module
+        else
+          get_next = true
+        end
+      end
+
+      return nil
+    end
+  end
+end
+
+-- ##############################################
+
+function system_scripts.getTasks()
+  local tasks = pairsByKeys(ntop.readdir(system_scripts_dir))
+
+  return function()
+    local get_next = true
+
+    while get_next do
+      local task = tasks()
+      get_next = false
+
+      if task then
+        local periodicity = task_to_periodicity[task]
+
+        if(periodicity ~= nil) then
+          return task, periodicity
+        else
+          get_next = true
+        end
+      else
+        return nil
+      end
+    end
+  end
+end
+
+-- ##############################################
+
+function system_scripts.runTask(task, when)
+  local old_new_schema_fn = ts_utils.newSchema
+  local periodicity = task_to_periodicity[task]
+  local default_schema_options = { step = periodicity }
+
+  if(periodicity == nil) then
+    return(false)
+  end
+
+  ts_utils.newSchema = function(name, label, options)
+    return old_new_schema_fn(name, table.merge(default_schema_options, options))
+  end
+
+  for _, probe in system_scripts.getSystemProbes(task) do
+    if(probe.runTask ~= nil) then
+      if(probe.loadSchemas ~= nil) then
+        -- Possibly load the schemas first
+        probe.loadSchemas(ts_utils)
+      end
+
+      probe.runTask(when, ts_utils)
+    end
+  end
+
+  -- Restore original function
+  ts_utils.newSchema = old_new_schema_fn
+  return(true)
+end
+
+-- ##############################################
+
+function system_scripts.getAdditionalTimeseries()
+  local old_new_schema_fn = ts_utils.newSchema
+  local additional_ts = {}
+  local needs_label = false
+  local current_probe_label = nil
+  local default_schema_options = nil
+
+  ts_utils.newSchema = function(name, options)
+    local schema = old_new_schema_fn(name, table.merge(default_schema_options, options))
+
+    if(options.label == nil) then
+      traceError(TRACE_ERROR, TRACE_CONSOLE, string.format("Missing schema label in schema '%s'", name))
+      return nil
+    end
+
+    if needs_label then
+      needs_label = false
+
+      additional_ts[#additional_ts + 1] = {
+        separator = 1,
+        label = current_probe_label,
+      }
+    end
+
+    additional_ts[#additional_ts + 1] = {
+      schema = name,
+      label = options.label,
+    }
+
+    return schema
+  end
+
+  for task, periodicity in system_scripts.getTasks() do
+    default_schema_options = { step = periodicity }
+
+    for probe_name, probe in system_scripts.getSystemProbes(task) do
+      if(probe.loadSchemas ~= nil) then
+        needs_label = true
+        current_probe_label = probe_name
+
+        probe.loadSchemas(ts_utils)
+      end
+    end
+  end
+
+  -- Restore original function
+  ts_utils.newSchema = old_new_schema_fn
+
+  return(additional_ts)
+end
+
+-- ##############################################
+
+return system_scripts