I'd like to allow our developers to pass dynamic arguments to a helm template (Kubernetes job). Currently my arguments in the helm template are somewhat static (apart from certain values) and look like this
Args:
--arg1
value1
--arg2
value2
--sql-cmd
select * from dbIf I were run a task using the docker container without Kubernetes, I would pass parameters like so:
docker run my-image --arg1 value1 --arg2 value2 --sql-cmd "select * from db"Is there any way to templatize arguments in a helm chart in such way that any number of arguments could be passed to a template.
For example.
cat values.yaml
...
arguments: --arg1 value1 --arg2 value2 --sql-cmd "select * from db"
...or
cat values.yaml
...
arguments: --arg3 value3
...I've tried a few approaches but was not successful. Here is one example:
Args:
{{ range .Values.arguments }}
{{ . }}
{{ end }}helm install --name "airflow" stable/airflow --set secrets.database=mydatabase,secrets.password=mypassword
So this is the helm chart in question: https://github.com/helm/charts/tree/master/stable/airflow Now I want to overwrite the default values in the helm chart secrets.database and secrets.password so I use --set argument and then it is key=value pairs separated by commas.helm install --name "<name for your chart>" <chart> --set key0=value0,key1=value1,key2=value2,key3=value3
Yes. In values.yaml you need to give it an array instead of a space delimited string.
cat values.yaml
...
arguments: ['--arg3', 'value3', '--arg2', 'value2']
...
or
cat values.yaml
...
arguments:
- --arg3
- value3
- --arg2
- value2
...
and then you like you mentioned in the template should do it:
args:
{{ range .Values.arguments }}
- {{ . }}
{{ end }}If you want to override the arguments on the command line you can pass an array with --set like this:
--set arguments={--arg1, value1, --arg2, value2, --arg3, value3, ....}In your values file define arguments as:
extraArgs:
argument1: value1
argument2: value2
booleanArg1:In your template do:
args:
{{- range $key, $value := .Values.extraArgs }}
{{- if $value }}
- --{{ $key }}={{ $value }}
{{- else }}
- --{{ $key }}
{{- end }}
{{- end }}Easy.
Rico's answer needed to be improved. Using the previous example I've received errors like:
templates/deployment.yaml: error converting YAML to JSON: yaml or
failed to get versionedObject: unable to convert unstructured object to apps/v1beta2, Kind=Deployment: cannot restore slice from string
This is my working setup with coma in elements: ( the vertical format for the list is more readable )
cat values.yaml ... arguments: [ "--arg3,", "value3,", "--arg2,", "value2,", ] ...
in the template should do it:
```
args: [
{{ range .Values.arguments }}
{{ . }}
{{ end }}
]
```