Below are various sample code that demonstrates various use-cases you may encounter writing custom actions:
Get a booth owner
Within the ++ action arm of your custom action handler, obtain booth information using the following hoon:
:: note that store and context are both provided in the outer/parent core in
:: which the 'on' arm resides
=/ booth (~(get by booths.store) booth-key.context)
:: the call above will return an object of type (unit json)
:: you'll want to ensure this is not null, and if not, grab the inner
:: json object using `need`
=/ booth ?~(booth ~ (need booth))
:: at this point, booth will either be null or a valid json object. however,
:: before you can work with the booth as json, you'll need to verify it's a valid
:: json type using the following code
=/ booth ?:(?=([%o *] booth) p.booth ~)
:: here, booth will be a (map @t json) instance or null (default of map). from this
:: point forward you can, manipulate/query the booth data using stdlib map functions
:: for example, if you wanted to get the booth owner:
=/ booth-owner (~(get by booth) 'owner')
=/ booth-owner ?~(booth-owner '' (so:dejs:format (need booth-owner)))
:: booth-owner here is either empty string (not found) or the owner
:: (ship name e.g. ~zod)
...
Get a proposal's strategy
Within the ++ action arm of your custom action handler, obtain booth information using the following hoon. Remember that within the context of the custom-action handler (outer core's ++ on gate), you have both a booth-key and proposal-key in the context.
Therefore given booth-key and proposal-key (both in custom action context), you can obtain the detail of a proposal as follows:
:: get a dictionary (map @t json) of proposals for a given booth (by booth-key)
=/ proposals (~(get by proposals.store) booth-key.context)
=/ proposals ?~(proposals ~ (need proposals))
=/ proposals ?:(?=([%o *] proposals) p.proposals ~)
:: get a specific proposal (json) within a booth by querying the proposals
:: return by the calls above
=/ proposal (~(get by proposals) proposal-key.context)
=/ proposal ?~(proposal ~ (need proposal))
=/ proposal ?:(?=([%o *] proposal) p.proposal ~)
:: query the proposal as needed (see proposal detail below)
:: for example, to get the proposal's voting strategy
=/ strategy (~(get by proposal) 'strategy')
=/ strategy ?~(strategy 'unknown' (so:dejs:format (need strategy)))
:: strategy will either be 'unknown' (not exists in json)
:: or strategy value (e.g. 'single-choice')
...
Get a participant's role
:: get a dictionary (map @t json) of participants for a given booth (by booth-key)
=/ participants (~(get by participants.store) booth-key.context)
=/ participants ?~(participants ~ (need participants))
=/ participants ?:(?=([%o *] participants) p.participants ~)
:: get a specific participant (json) within a booth by querying the participants
:: return by the calls above
=/ participant (~(get by participants) participant-key.context)
=/ participant ?~(participant ~ (need prparticipantoposal))
=/ participant ?:(?=([%o *] participant) p.participant ~)
:: query the participant as needed (see participant detail below)
:: for example, to get the participant's role
=/ role (~(get by participant) 'role')
=/ role ?~(role 'unknown' (so:dejs:format (need role)))
:: role will either be 'unknown' (not exists in json)
:: or role value (e.g. 'member')
...
