lua script for parsing faction names out of the journal (unnecessary comments version)

_factionNames.lua

local json = require('json')
local fs = require('fs')
local results_t = {}

-- the options we're parsing for:
--[[
rootTags_t
    "Factions":[ { (LOTS OF STUFF) } ]
    "Rewards":[ { "Faction":"89 Leonis Republic Party", "Reward":132097 } ]
    "StationFaction":{ "Name":"89 Leonis Republic Party" }
    "SystemFaction":{ "Name":"89 Leonis Republic Party" }
    "VictimFaction":"89 Leonis Republic Party" 
]]--
local rootTags_t = {'Factions', 'Rewards', 'StationFaction', 'SystemFaction', 'VictimFaction'}

-- subTags_t are just tags used within rootTags_t, e.g., "StationFaction":{ "Name":
local subTags_t = {'Name', 'Faction'}

local function tableScan_f(input_t, nest_s)
    -- nest_s flag: trigger set when a rootTags_t is detected
    if type(input_t) == 'table' and nest_s then
        for _, v in pairs(input_t) do
            for _, b in pairs(subTags_t) do -- iterate over subTags_t options
                if v[b] then
                    results_t[v[b]] = '' -- bingo, add the faction name
                end
            end
        end
    elseif type(input_t) == 'table' then
        for _, v in pairs(rootTags_t) do -- iterate over rootTags_t options
            if input_t[v] then
                tableScan_f(input_t[v], v) -- found a rootTags_t, activate nest_s so we can scan recursively
            end
        end
    else
        results_t[input_t] = '' -- bingo, whatever survives is a faction name
    end
    return
end

-- main execution; parse the received journal file listing
local function parse_f(files_t)
    for _, file in pairs(files_t) do
        local f = io.open(file, 'r')
        for line in f:lines() do -- read the file one line at a time
            local scrub_t = json.decode(line) -- attempt to convert line to JSON
            if scrub_t then -- if successful, continue (error handling)
                tableScan_f(scrub_t)
            end
        end -- so many ends... never meet your heroes
        f:close()
    end
    
    -- spit it all out into the file '_factionNames.txt'
    local f = io.open('_factionNames.txt', "wb")
    for k, _ in pairs(results_t) do
        f:write(k .. '\n')
    end
    f:close()
end


-- initial execution; scan the current directory for all files
local files_t = {}
fs.readdir('.', function(_, v)
    for _, filename in pairs(v) do
        -- store the filename if begins with 'Journal' and ends with '.log'
        if string.match(filename, '^Journal.+%log$') then files_t[#files_t + 1] = filename end
    end
    -- pass off to main execution
    parse_f(files_t)
end)