Create custom Time field

[NCATS LAB]

I am looking for a way to create a field that supports only Time - NOT DateTime. I want to be able to enter a time in H:mm format. I know about exiting the global context for jira.date.time.picker.java.format, but I have other fields that need this. I can't use Number field, as I can't enter colons. I don't want a text field, as this needs to be a valid time format.

I have tried to add the following in the description of a custom field:

<script type="text/javascript">
{document.getElementById("customfield_11700").format = "H:mm";}
</script>

but this does not seem to work.

When trying to manually edit, I get:

customfield_11700: Invalid date format. Please enter the date in the format "dd/MMM/yy h:mm a".

I think the best way forward would be to somehow override the validation, but I can't seem to figure out how.

I would prefer to do this with javascript injection instead of a plug-in, as I am not authorized to acquire any more plugins (and we do not have script-runner).

[Nic Brough -Adaptavist-]

You will need to find or write an app that provides a custom field of this type.

[NCATS LAB]

Nic, thank you for your response. Do you have any recommendations on where to begin?

[Nic Brough -Adaptavist-]

Probably https://developer.atlassian.com/server/jira/platform/getting-started/ if you can't find anything in https://marketplace.atlassian.com