How to pass dynamic arguments to a helm chart that runs a job

Question

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 db

If 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 }}

Answer 1

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, ....}