Add code to localise graph templates

[collecty.git] / src / collecty / plugins / base.py

diff --git a/src/collecty/plugins/base.py b/src/collecty/plugins/base.py
index cf9c3b402410bf085fd7b0e825644aef42d6fba4..c9e815c52d48ebd831af1a5a05f188adc0473df9 100644 (file)
--- a/src/collecty/plugins/base.py
+++ b/src/collecty/plugins/base.py
@@ -29,6 +29,7 @@ import threading
 import time
 import unicodedata
 
+from .. import locales
 from ..constants import *
 from ..i18n import _
 
@@ -64,6 +65,41 @@ class Timer(object):
                return self.elapsed > self.timeout
 
 
+class Environment(object):
+       """
+               Sets the correct environment for rrdtool to create
+               localised graphs and graphs in the correct timezone.
+       """
+       def __init__(self, timezone, locale):
+               # Build the new environment
+               self.new_environment = {
+                       "TZ" : timezone or DEFAULT_TIMEZONE,
+               }
+
+               for k in ("LANG", "LC_ALL"):
+                       self.new_environment[k] = locale or DEFAULT_LOCALE
+
+       def __enter__(self):
+               # Save the current environment
+               self.old_environment = {}
+               for k in self.new_environment:
+                       self.old_environment[k] = os.environ.get(k, None)
+
+               # Apply the new one
+               os.environ.update(self.new_environment)
+
+       def __exit__(self, type, value, traceback):
+               # Roll back to the previous environment
+               for k, v in self.old_environment.items():
+                       if v is None:
+                               try:
+                                       del os.environ[k]
+                               except KeyError:
+                                       pass
+                       else:
+                               os.environ[k] = v
+
+
 class PluginRegistration(type):
        plugins = {}
 
@@ -195,15 +231,17 @@ class Plugin(object, metaclass=PluginRegistration):
 
                        return object
 
-       def get_template(self, template_name, object_id):
+       def get_template(self, template_name, object_id, locale=None, timezone=None):
                for template in self.templates:
                        if not template.name == template_name:
                                continue
 
-                       return template(self, object_id)
+                       return template(self, object_id, locale=locale, timezone=timezone)
 
-       def generate_graph(self, template_name, object_id="default", **kwargs):
-               template = self.get_template(template_name, object_id=object_id)
+       def generate_graph(self, template_name, object_id="default",
+                       timezone=None, locale=None, **kwargs):
+               template = self.get_template(template_name, object_id=object_id,
+                       timezone=timezone, locale=locale)
                if not template:
                        raise RuntimeError("Could not find template %s" % template_name)
 
@@ -401,9 +439,13 @@ class GraphTemplate(object):
        height = GRAPH_DEFAULT_HEIGHT
        width  = GRAPH_DEFAULT_WIDTH
 
-       def __init__(self, plugin, object_id):
+       def __init__(self, plugin, object_id, locale=None, timezone=None):
                self.plugin = plugin
 
+               # Save localisation parameters
+               self.locale = locales.get(locale)
+               self.timezone = timezone
+
                # Get all required RRD objects
                self.object_id = object_id
 
@@ -505,6 +547,7 @@ class GraphTemplate(object):
                # Convert arguments to string
                args = [str(e) for e in args]
 
-               graph = rrdtool.graphv("-", *args)
+               with Environment(self.timezone, self.locale.lang):
+                       graph = rrdtool.graphv("-", *args)
 
                return graph.get("image")