Hooks#

Hooks let your resource block, rewrite or react to MDT actions, no matter where they come from: the tablet, the web portal, a server export or an automatic job.

local hookId = exports['koja-mdt']:registerHook(name, function(payload, src)
end, { stage = 'before', priority = 0 })

registerHook returns the hook id, or nil, 'unknown_hook' / nil, 'invalid_function'. removeHook(hookId) removes it (only the resource that registered it can). Hooks are removed automatically when your resource stops. GetHookNames() lists every name.

Semantics#

1. Before hooks#

   • Return false to cancel. Return a reason as the second value to show the officer a specific error: return false, 'over_limit' (64 chars max). The first hook that cancels wins and later hooks do not run.
   • Return a table to change the payload. Its keys are merged into the payload and passed to the next hook. Only the fields marked modifiable below are applied; everything else is informational. Values are validated again after your hook (lengths, ranges, enums).
   • Payloads are copies when they cross resources, so changing payload in place has no effect. Return the changes.
   • Returning nothing (or true) lets the action continue unchanged.
   • Errors are caught and printed to the console; a failing hook never blocks the MDT.

2. After hooks#

   After hooks run asynchronously once the action is saved. Return values are ignored. Each after stage is also fired as a server event, see the event bridge below.

3. Arguments#

   src is the acting player's server id, or nil for web portal, export and system actions. Most payloads carry by (or officer / unit): { source, identifier, name, callsign, department, system }. system = true marks System and export actions.

Event bridge#

Every after stage is also triggered as a server-local event named koja-mdt:<hook> with (payload, src). Use it if you prefer events over hooks. It cannot cancel anything.

AddEventHandler('koja-mdt:warrant:approve', function(payload, src)
    print(('warrant #%d approved by %s'):format(payload.id, payload.by and payload.by.name or 'System'))
end)

Use AddEventHandler, never RegisterNetEvent: clients cannot trigger these.

Dispatch#

exports['koja-mdt']:registerHook('dispatch:create', function(call)
    if call.code == '10-90' then return { priority = 1, message = (call.message or '') .. ' [bank]' } end
end, { stage = 'before' })

Records#

exports['koja-mdt']:registerHook('incident:process', function(payload)
    if payload.months > 60 then return { months = 60 } end
end, { stage = 'before' })

exports['koja-mdt']:registerHook('citation:create', function(payload, src)
    if payload.total > 5000 then return false, 'over_limit' end
end, { stage = 'before' })

Officers and tablet#

exports['koja-mdt']:registerHook('mdt:open', function(payload)
    return exports.ox_inventory:Search(payload.source, 'count', 'mdt_tablet') > 0
end, { stage = 'before' })

Communication#

Custody#

Court#

EMS#

ANPR#

Bodycam recordings#

exports['koja-mdt']:registerHook('bodycam:recordingSaved', function(payload)
    print(('bodycam session %s saved, %d frames'):format(payload.sessionId, payload.frames))
end)

Recipes#

exports['koja-mdt']:registerHook('warrant:create', function(payload, src)
    if payload.type == 'search' and not payload.reason:find('affidavit') then
        return false, 'affidavit_required'
    end
end, { stage = 'before' })

exports['koja-mdt']:registerHook('jail:create', function(payload)
    if payload.months > 120 then return { months = 120, reason = (payload.reason or '') .. ' (capped)' } end
end, { stage = 'before' })

exports['koja-mdt']:registerHook('hospital:admit', function(payload)
    exports['my-hospital']:ReserveBed(payload.admission.hospital, payload.admission.bed)
end)