diff options
Diffstat (limited to 'source/rainerscript/functions/rs-lookup.rst')
| -rw-r--r-- | source/rainerscript/functions/rs-lookup.rst | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/source/rainerscript/functions/rs-lookup.rst b/source/rainerscript/functions/rs-lookup.rst new file mode 100644 index 0000000..cdcd563 --- /dev/null +++ b/source/rainerscript/functions/rs-lookup.rst @@ -0,0 +1,33 @@ +******** +lookup() +******** + +Purpose +======= + +lookup(table_name_literal_string, key) + +Lookup tables are a powerful construct to obtain *class* information based +on message content. It works on top of a data-file which maps key (to be looked +up) to value (the result of lookup). + +The idea is to use a message properties (or derivatives of it) as an index +into a table which then returns another value. For example, $fromhost-ip +could be used as an index, with the table value representing the type of +server or the department or remote office it is located in. + +**Read more about it here** :doc:`Lookup Tables<../../configuration/lookup_tables>` + + +Example +======= + +In the following example the hostname is looked up in the given table and +the corresponding value is returned. + +.. code-block:: none + + lookup_table(name="host_bu" file="/var/lib/host_billing_unit_mapping.json") + set $.bu = lookup("host_bu", $hostname); + + |