modules/predict: cleaned up unused function, variables, trailing whitespace

The `stats` module is now also included if not exists.

```
$ luacheck modules/predict
Checking modules/predict/predict.lua              OK

Total: 0 warnings / 0 errors in 1 file
```

diff --git a/modules/predict/predict.lua b/modules/predict/predict.lua
index 79c52f48104683204e52b46dd48091ff4c709e1f..d0f550ba84f5ff8d7eb8c8c8fac5a5fd93c0d367 100644 (file)
--- a/modules/predict/predict.lua
+++ b/modules/predict/predict.lua
@@ -13,6 +13,9 @@ local predict = {
        log = {},
 }
 
+-- Load dependent modules
+if not stats then modules.load('stats') end
+
 -- Calculate current epoch (which window fits current time)
 local function current_epoch()
        if not predict.period or predict.period <= 1 then return nil end
@@ -27,9 +30,9 @@ local function next_event()
 end
 
 -- Resolve queued records and flush the queue
-function predict.drain(ev)
+function predict.drain()
        local deleted = 0
-       for key, val in pairs(predict.queue) do
+       for key, _ in pairs(predict.queue) do
                local qtype, qname = key:match('(%S*)%s(.*)')
                worker.resolve(qname, kres.type[qtype], kres.class.IN, 'NO_CACHE')
                predict.queue[key] = nil
@@ -48,26 +51,11 @@ function predict.drain(ev)
        return 0
 end
 
--- Enqueue queries from set
-local function enqueue(queries)
-       local queued = 0
-       local nr_queries = #queries
-       for i = 1, nr_queries do
-               local entry = queries[i]
-               local key = string.format('%s %s', entry.type, entry.name)
-               if not predict.queue[key] then
-                       predict.queue[key] = 1
-                       queued = queued + 1
-               end
-       end
-       return queued   
-end
-
--- Enqueue queries from same format as predict.queue or predict.log 
+-- Enqueue queries from same format as predict.queue or predict.log
 local function enqueue_from_log(current)
        if not current then return 0 end
-       queued = 0
-       for key, val in pairs(current) do 
+       local queued = 0
+       for key, val in pairs(current) do
                if val and not predict.queue[key] then
                        predict.queue[key] = val
                        queued = queued + 1
@@ -79,7 +67,7 @@ end
 -- Sample current epoch, return number of sampled queries
 function predict.sample(epoch_now)
        if not epoch_now then return 0, 0 end
-       local current = predict.log[epoch_now] or {}    
+       local current = predict.log[epoch_now] or {}
        local queries = stats.frequent()
        stats.clear_frequent()
        local nr_samples = #queries
@@ -100,7 +88,7 @@ local function generate(epoch_now)
                local current = predict.log[(epoch_now - i - 1) % predict.period + 1]
                local past = predict.log[(epoch_now - 2*i - 1) % predict.period + 1]
                if current and past then
-                       for k, v in pairs(current) do
+                       for k, _ in pairs(current) do
                                if past[k] ~= nil and not predict.queue[k] then
                                        queued = queued + 1
                                        predict.queue[k] = 1
@@ -111,30 +99,27 @@ local function generate(epoch_now)
        return queued
 end
 
-function predict.process(ev)
-       if (predict.period or 0) ~= 0 and not stats then
-               error("'stats' module required")
-       end
+function predict.process()
        -- Start a new epoch, or continue sampling
        predict.ev_sample = nil
        local epoch_now = current_epoch()
        local nr_queued = 0
 
-       -- End of epoch 
+       -- End of epoch
        if predict.epoch ~= epoch_now then
                stats['predict.epoch'] = epoch_now
                predict.epoch = epoch_now
-               -- enqueue records from upcoming epoch  
+               -- enqueue records from upcoming epoch
                nr_queued = enqueue_from_log(predict.log[epoch_now])
                -- predict next epoch
                nr_queued = nr_queued + generate(epoch_now)
                -- clear log for new epoch
                predict.log[epoch_now] = {}
        end
-       
+
        -- Sample current epoch
        local nr_learned = predict.sample(epoch_now)
-       
+
        -- Dispatch predicted queries
        if nr_queued > 0 then
                predict.queue_len = predict.queue_len + nr_queued
@@ -151,14 +136,14 @@ function predict.process(ev)
        collectgarbage()
 end
 
-function predict.init(module)
+function predict.init()
        if predict.window > 0 then
                predict.epoch = current_epoch()
                predict.ev_sample = event.after(next_event(), predict.process)
        end
 end
 
-function predict.deinit(module)
+function predict.deinit()
        if predict.ev_sample then event.cancel(predict.ev_sample) end
        if predict.ev_drain then event.cancel(predict.ev_drain) end
        predict.ev_sample = nil
@@ -182,7 +167,7 @@ end
 predict.layer = {
        -- Prefetch all expiring (sub-)queries immediately after the request finishes.
        -- Doing that immediately is simplest and avoids creating (new) large bursts of activity.
-       finish = function (state, req)
+       finish = function (_, req)
                req = kres.request_t(req)
                local qrys = req.rplan.resolved
                for i = 0, (tonumber(qrys.len) - 1) do -- size_t doesn't work for some reason