gosora/common/counters/forums.go

119 lines
3.2 KiB
Go

package counters
import (
"database/sql"
"sync"
".."
"../../query_gen/lib"
)
var ForumViewCounter *DefaultForumViewCounter
// TODO: Unload forum counters without any views over the past 15 minutes, if the admin has configured the forumstore with a cap and it's been hit?
// Forums can be reloaded from the database at any time, so we want to keep the counters separate from them
type DefaultForumViewCounter struct {
oddMap map[int]*RWMutexCounterBucket // map[fid]struct{counter,sync.RWMutex}
evenMap map[int]*RWMutexCounterBucket
oddLock sync.RWMutex
evenLock sync.RWMutex
insert *sql.Stmt
}
func NewDefaultForumViewCounter() (*DefaultForumViewCounter, error) {
acc := qgen.Builder.Accumulator()
counter := &DefaultForumViewCounter{
oddMap: make(map[int]*RWMutexCounterBucket),
evenMap: make(map[int]*RWMutexCounterBucket),
insert: acc.Insert("viewchunks_forums").Columns("count, createdAt, forum").Fields("?,UTC_TIMESTAMP(),?").Prepare(),
}
common.AddScheduledFifteenMinuteTask(counter.Tick) // There could be a lot of routes, so we don't want to be running this every second
//common.AddScheduledSecondTask(counter.Tick)
common.AddShutdownTask(counter.Tick)
return counter, acc.FirstError()
}
func (counter *DefaultForumViewCounter) Tick() error {
counter.oddLock.RLock()
oddMap := counter.oddMap
counter.oddLock.RUnlock()
for forumID, forum := range oddMap {
var count int
forum.RLock()
count = forum.counter
forum.RUnlock()
// TODO: Only delete the bucket when it's zero to avoid hitting popular forums?
counter.oddLock.Lock()
delete(counter.oddMap, forumID)
counter.oddLock.Unlock()
err := counter.insertChunk(count, forumID)
if err != nil {
return err
}
}
counter.evenLock.RLock()
evenMap := counter.evenMap
counter.evenLock.RUnlock()
for forumID, forum := range evenMap {
var count int
forum.RLock()
count = forum.counter
forum.RUnlock()
// TODO: Only delete the bucket when it's zero to avoid hitting popular forums?
counter.evenLock.Lock()
delete(counter.evenMap, forumID)
counter.evenLock.Unlock()
err := counter.insertChunk(count, forumID)
if err != nil {
return err
}
}
return nil
}
func (counter *DefaultForumViewCounter) insertChunk(count int, forum int) error {
if count == 0 {
return nil
}
common.DebugLogf("Inserting a viewchunk with a count of %d for forum %d", count, forum)
_, err := counter.insert.Exec(count, forum)
return err
}
func (counter *DefaultForumViewCounter) Bump(forumID int) {
// Is the ID even?
if forumID%2 == 0 {
counter.evenLock.RLock()
forum, ok := counter.evenMap[forumID]
counter.evenLock.RUnlock()
if ok {
forum.Lock()
forum.counter++
forum.Unlock()
} else {
counter.evenLock.Lock()
counter.evenMap[forumID] = &RWMutexCounterBucket{counter: 1}
counter.evenLock.Unlock()
}
return
}
counter.oddLock.RLock()
forum, ok := counter.oddMap[forumID]
counter.oddLock.RUnlock()
if ok {
forum.Lock()
forum.counter++
forum.Unlock()
} else {
counter.oddLock.Lock()
counter.oddMap[forumID] = &RWMutexCounterBucket{counter: 1}
counter.oddLock.Unlock()
}
}
// TODO: Add a forum counter backed by two maps which grow as forums are created but never shrinks