Caching the entire spellbook securely?

[MunkDev]

I'm trying to cache the entire spellbook securely, which kind of works in this hacky fashion posted below, but should I really have to use pcall to loop through the entire spellbook without causing a heap of lua errors? I tried to find appropriate functions on wowprogramming, but I came up empty handed.

The reason I want to do this is to be able to determine what kind of spell is situated on every action button. After trying a bunch of different things with the scrubbed GetActionInfo and failing to get proper results from IsHarmfulSpell/IsHelpfulSpell securely, this was the only approach that worked.

-- Run this in response to a talent update
local function SecureSpellBookUpdate()
    Cursor:Execute([[ SPELLS = wipe(SPELLS) ]])
    for id=1, MAX_SPELLS do
        local ok, err, _, _, _, _, _, spellID = pcall(GetSpellInfo, id, "spell")
        if ok then
            Cursor:Execute(format([[
                SPELLS[%d] = %d
            ]], spellID, id))
        else
            break
        end
    end
end
 
Cursor:SetAttribute("RefreshActions", [[
    Helpful = wipe(Helpful)
    Harmful = wipe(Harmful)
    for actionButton in pairs(Actions) do
        local action = actionButton:GetAttribute("action")
        local id = action >= 0 and action <= 12 and (PAGE-1) * 12 + action or action >= 0 and action
        if id then
            local actionType, actionID, subType = GetActionInfo(id)
            if actionType == "spell" and subType == "spell" then
                local spellBookID = SPELLS[actionID]
                local helpful = spellBookID and IsHelpfulSpell(spellBookID, "spell")
                local harmful = spellBookID and IsHarmfulSpell(spellBookID, "spell")
                if helpful then
                    Helpful[actionButton] = true
                elseif harmful then
                    Harmful[actionButton] = true
                else
                    Helpful[actionButton] = true
                    Harmful[actionButton] = true
                end
            end
        end
    end
]])