Changes between Version 7 and Version 8 of Usage/UserDocumentation

Timestamp:

06/04/12 17:18:59 (12 years ago)

Author:

sil

Comment:

adde documentation about CMT templates

Usage/UserDocumentation

@@ -384 +384 @@
 = CMT Templates =
 
-CMT offers a powerful feature, powered by templates based on the [https://docs.djangoproject.com/en/dev/topics/templates/ Django Template Language].
-With these template-files you're able to let CMT generate various kind of files, like configuration files or reports about your clusters.
+CMT offers a powerful feature, powered by templates.
+With these templates you're able to let CMT generate various kind of files, like configuration files or reports about your clusters.
+
+The syntax of the templates in CMT is based on Django templates, therefore the documentation of the [https://docs.djangoproject.com/en/dev/topics/templates/ Django template language] can be useful as a reference.
+Django templates are usually meant for web pages, but since we use it for our configuration files some functionalities have been added for CMT-specific needs.
+By extending the Django template language, it has been made possible to:
+ * Define an epilogue script
+ * Pre-load datasets from database
+ * Set a path to write the output to
+
+To make use of these functionalities you have to start your template with
+
+{{{
+{% load cmt_client %}
+}}}
+
+and store the file in your template-directory as `<name>.cmt`
+
+
+== Epilogue script ==
+
+Some configuration files need to be reloaded by the program when they are modified.
+Or maybe some other things should be done to activate the new configuration.
+This is where an epilogue script comes in.
+You can write the epilogue script in the template itself, between the ''epilogue'' and ''endepilogue'' tag:
+
+{{{
+{% epilogue %}
+# this epilogue-script will restart the DHCP server
+/etc/init.d/dhcp3-server restart
+{% endepilogue %}
+}}}
+
+
+== Pre-load datasets from database ==
+
+You may define collections of objects to use in your templates.
+These collections can be defined with a filter, and assigning it to a variable name to use.
+
+{{{
+# syntax for the use-tag is:
+#  use <entity> with <filter> as <variable name>
+{% use network with 'name=lisa consoles' as net_consoles %}
+{% use interface with 'network__name=lisa consoles' as ifaces_consoles %}
+}}}
+
+In the example two collections are assigned to a variable:
+ * `net_consoles` will contain the network with the name ''lisa consoles''
+ * `ifaces_consoles` will contain all interfaces in that network
+
+Now these collections can be used in the template, to build a part of a DHCP config-file for example:
+
+{{{
+group { # Start Console network
+    option domain-name "{{net_consoles.domain}}";
+
+    {% for iface in ifaces_consoles %}
+    {% if iface.hwaddress != None %}
+    host {{iface.fqdn}} {
+        hardware ethernet {{iface.hwaddress}};
+        fixed-address {{iface.ip}};
+        option host-name "{{iface.fqdn}}";
+    }
+    {% endif %}
+    {% endfor %}
+} # End Console network
+}}}
+
+
+== Set a path to write the output to ==
+
+To save the result of your template, you can store the output to a file.
+This can be done by using the ''store''-tag, and give it a path:
+{{{
+# syntax for the store-tag is:
+#  store <outputpath>  as output
+{% store /etc/dhcp/dhcpd.conf as output %}
+}}}
+
+In this example the result will be written to `/etc/dhcp/dhcp.conf`.