Fluent Bit allows us to build filter to modify the incoming records using custom [Lua scripts.](https://docs.fluentbit.io/manual/pipeline/filters/lua)
### How to use Lua scripts with this Chart
First, you should add your Lua scripts to `luaScripts` in values.yaml, for example:
```yaml
luaScripts:
filter_example.lua: |
function filter_name(tag, timestamp, record)
-- put your lua code here.
end
```
After that, the Lua scripts will be ready to be used as filters. So next step is to add your Fluent bit [filter](https://docs.fluentbit.io/manual/concepts/data-pipeline/filter) to `config.filters` in values.yaml, for example:
```yaml
config:
filters: |
[FILTER]
Name lua
Match <your-tag>
script /fluent-bit/scripts/filter_example.lua
call filter_name
```
Under the hood, the chart will:
- Create a configmap using `luaScripts`.
- Add a volumeMounts for each Lua scripts using the path `/fluent-bit/scripts/<script>`.
- Add the Lua script's configmap as volume to the pod.
### Note
Remember to set the `script` attribute in the filter using `/fluent-bit/scripts/`, otherwise the file will not be found by fluent bit.