cloudfoundry-incubator/stratos

package sessiondata

import (
    "time"

    log "github.com/sirupsen/logrus"
)

var defaultInterval = time.Minute * 5

// Cleanup runs a background goroutine every interval that deletes expired
// sessions from the database.
//
// The design is based on https://github.com/yosssi/boltstore
func (m *SessionDataRepository) Cleanup(interval time.Duration) (chan<- struct{}, <-chan struct{}) {
    if interval <= 0 {
        interval = defaultInterval
    }

    quit, done := make(chan struct{}), make(chan struct{})
    go m.cleanup(interval, quit, done)
    return quit, done
}

// StopCleanup stops the background cleanup from running.
func (m *SessionDataRepository) StopCleanup(quit chan<- struct{}, done <-chan struct{}) {
    quit <- struct{}{}
    <-done
}

// cleanup deletes expired sessions at set intervals.
func (m *SessionDataRepository) cleanup(interval time.Duration, quit <-chan struct{}, done chan<- struct{}) {
    ticker := time.NewTicker(interval)

    defer func() {
        ticker.Stop()
    }()

    for {
        select {
        case <-quit:
            // Handle the quit signal.
            done <- struct{}{}
            return
        case <-ticker.C:
            // Delete expired sessions on each tick.
            err := m.deleteExpired()
            if err != nil {
                log.Printf("SessionDataRepository: unable to delete expired sessions: %v", err)
            }
        }
    }
}

// deleteExpired will delete session values when the session expires
func (c *SessionDataRepository) deleteExpired() error {
    log.Debug("Expiring session data")
    _, err := c.db.Exec(expireSessionData)
    if err != nil {
        return err
    }
    _, err = c.db.Exec(deleteSessionData)
    return err
}