From 8ee5a71a80e7361880f7719bdd3398403ddb4401 Mon Sep 17 00:00:00 2001
From: Michael Tremer <michael.tremer@ipfire.org>
Date: Mon, 23 Nov 2015 03:19:04 +0000
Subject: [PATCH] Add lastupdate()

Allow to request the latest dataset of the database so
that sensory data can be shown at various other places, too.

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---
 src/collecty/bus.py          | 13 ++++++++++++
 src/collecty/client.py       | 27 ++++++++++++++++++++++++
 src/collecty/daemon.py       |  7 +++++++
 src/collecty/plugins/base.py | 40 ++++++++++++++++++++++++++++++++++++
 4 files changed, 87 insertions(+)

diff --git a/src/collecty/bus.py b/src/collecty/bus.py
index fe22fea..7c84285 100644
--- a/src/collecty/bus.py
+++ b/src/collecty/bus.py
@@ -98,6 +98,19 @@ class GraphGenerator(dbus.service.Object):
 		"""
 		return self.collecty.graph_info(template_name, **kwargs)
 
+	@dbus.service.method(BUS_DOMAIN, in_signature="sa{sv}", out_signature="a{sv}")
+	def LastUpdate(self, template_name, kwargs):
+		"""
+			Returns a graph generated from the given template and object.
+		"""
+		last_update = self.collecty.last_update(template_name, **kwargs)
+
+		# Serialise datetime as string
+		if last_update:
+			last_update["timestamp"] = last_update["timestamp"].isoformat()
+
+		return last_update
+
 	@dbus.service.method(BUS_DOMAIN, in_signature="", out_signature="as")
 	def ListTemplates(self):
 		"""
diff --git a/src/collecty/client.py b/src/collecty/client.py
index 7989d11..be898bb 100644
--- a/src/collecty/client.py
+++ b/src/collecty/client.py
@@ -20,6 +20,7 @@
 ###############################################################################
 
 import argparse
+import datetime
 import dbus
 import os
 import platform
@@ -37,6 +38,23 @@ class CollectyClient(object):
 
 		self.proxy = self.bus.get_object(BUS_DOMAIN, "/GraphGenerator")
 
+	def last_update(self, template_name, **kwargs):
+		last_update = self.proxy.LastUpdate(template_name, kwargs)
+
+		if last_update:
+			last_update["timestamp"] = datetime.datetime.strptime(last_update["timestamp"], "%Y-%m-%dT%H:%M:%S")
+
+		return last_update
+
+	def last_update_cli(self, ns):
+		last_update = self.last_update(ns.template, object_id=ns.object)
+
+		print(_("Last update: %s") % last_update.get("timestamp"))
+
+		dataset = last_update.get("dataset")
+		for k, v in dataset.items():
+			print("%16s = %s" % (k, v))
+
 	def list_templates(self):
 		templates = self.proxy.ListTemplates()
 
@@ -136,6 +154,15 @@ class CollectyClient(object):
 		parser_generate_graph.add_argument("--width", type=int, default=0,
 			help=_("Width of the generated image"))
 
+		# last-update
+		parser_last_update = subparsers.add_parser("last-update",
+			help=_("Fetch the last dataset in the database"))
+		parser_last_update.add_argument("--template",
+			help=_("The graph template identifier"), required=True)
+		parser_last_update.add_argument("--object",
+			help=_("Object identifier"), default="default")
+		parser_last_update.set_defaults(func=self.last_update_cli)
+
 		# list-templates
 		parser_list_templates = subparsers.add_parser("list-templates",
 			help=_("Lists all graph templates"))
diff --git a/src/collecty/daemon.py b/src/collecty/daemon.py
index e8d402e..d4e9b4a 100644
--- a/src/collecty/daemon.py
+++ b/src/collecty/daemon.py
@@ -203,6 +203,13 @@ class Collecty(object):
 
 		return plugin.graph_info(template_name, *args, **kwargs)
 
+	def last_update(self, template_name, *args, **kwargs):
+		plugin = self.get_plugin_from_template(template_name)
+		if not plugin:
+			raise RuntimeError("Could not find template %s" % template_name)
+
+		return plugin.last_update(*args, **kwargs)
+
 	def create_worker_threads(self, num=None):
 		"""
 			Creates a number of worker threads
diff --git a/src/collecty/plugins/base.py b/src/collecty/plugins/base.py
index ca98ef7..04207c7 100644
--- a/src/collecty/plugins/base.py
+++ b/src/collecty/plugins/base.py
@@ -264,6 +264,13 @@ class Plugin(object, metaclass=PluginRegistration):
 
 		return template.graph_info()
 
+	def last_update(self, object_id="default"):
+		object = self.get_object(object_id)
+		if not object:
+			raise RuntimeError("Could not find object %s" % object_id)
+
+		return object.last_update()
+
 
 class Object(object):
 	# The schema of the RRD database.
@@ -359,6 +366,39 @@ class Object(object):
 	def info(self):
 		return rrdtool.info(self.file)
 
+	def last_update(self):
+		"""
+			Returns a dictionary with the timestamp and
+			data set of the last database update.
+		"""
+		return {
+			"dataset"   : self.last_dataset,
+			"timestamp" : self.last_updated,
+		}
+
+	def _last_update(self):
+		return rrdtool.lastupdate(self.file)
+
+	@property
+	def last_updated(self):
+		"""
+			Returns the timestamp when this database was last updated
+		"""
+		lu = self._last_update()
+
+		if lu:
+			return lu.get("date")
+
+	@property
+	def last_dataset(self):
+		"""
+			Returns the latest dataset in the database
+		"""
+		lu = self._last_update()
+
+		if lu:
+			return lu.get("ds")
+
 	@property
 	def stepsize(self):
 		return self.plugin.interval
-- 
2.39.2