/
bunstore.go
180 lines (153 loc) · 5.04 KB
/
bunstore.go
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package bunstore
import (
"context"
"log"
"time"
"github.com/uptrace/bun"
"github.com/uptrace/bun/dialect"
)
// BunStore represents the session store.
type BunStore struct {
db *bun.DB
stopCleanup chan bool
}
type session struct {
bun.BaseModel `bun:"table:sessions,alias:sessions"`
Token string `bun:"token,pk"`
Data []byte `bun:"data"`
Expiry time.Time `bun:"expiry"`
}
// New returns a new BunStore instance, with a background cleanup goroutine
// that runs every 5 minutes to remove expired session data.
func New(db *bun.DB) (*BunStore, error) {
return NewWithCleanupInterval(db, 5*time.Minute)
}
// NewWithCleanupInterval returns a new BunStore instance. The cleanupInterval
// parameter controls how frequently expired session data is removed by the
// background cleanup goroutine. Setting it to 0 prevents the cleanup goroutine
// from running (i.e. expired sessions will not be removed).
func NewWithCleanupInterval(db *bun.DB, cleanupInterval time.Duration) (*BunStore, error) {
b := &BunStore{db: db}
if cleanupInterval > 0 {
go b.startCleanup(cleanupInterval)
}
return b, nil
}
// Find returns the data for a given session token from the BunStore instance.
// If the session token is not found or is expired, the returned exists flag will
// be set to false.
func (b *BunStore) FindCtx(ctx context.Context, token string) (bb []byte, exists bool, err error) {
s := &session{}
count, err := b.db.NewSelect().Model(s).Where("token = ? AND expiry >= ?", token, time.Now()).ScanAndCount(ctx)
if count == 0 {
return nil, false, nil
}
if err != nil {
return nil, false, err
}
return s.Data, true, nil
}
// Commit adds a session token and data to the BunStore instance with the
// given expiry time. If the session token already exists, then the data and expiry
// time are updated.
func (b *BunStore) CommitCtx(ctx context.Context, token string, bb []byte, expiry time.Time) error {
s := &session{Token: token, Data: bb, Expiry: expiry}
switch b.db.Dialect().Name() {
case dialect.SQLite:
if _, err := b.db.NewInsert().Model(s).Replace().Exec(ctx); err != nil {
return err
}
case dialect.PG:
if _, err := b.db.NewInsert().Model(s).On("CONFLICT (token) DO UPDATE").Set("data = EXCLUDED.data").Exec(ctx); err != nil {
return err
}
case dialect.MySQL:
if _, err := b.db.NewInsert().Model(s).On("DUPLICATE KEY UPDATE").Set("data = VALUES(data), expiry = VALUES(expiry)").Exec(ctx); err != nil {
return err
}
default:
panic("not reached")
}
return nil
}
// Delete removes a session token and corresponding data from the BunStore
// instance.
func (b *BunStore) DeleteCtx(ctx context.Context, token string) error {
_, err := b.db.NewDelete().Model(&session{}).Where("token = ?", token).Exec(ctx)
if err != nil {
return err
}
return nil
}
// All returns a map containing the token and data for all active (i.e.
// not expired) sessions in the BunStore instance.
func (b *BunStore) AllCtx(ctx context.Context) (map[string][]byte, error) {
rows, err := b.db.NewSelect().Model(&[]session{}).Where("expiry >= ?", time.Now()).Rows(ctx)
if err != nil {
return nil, err
}
defer rows.Close()
ss := make(map[string][]byte)
for rows.Next() {
s := &session{}
if err = b.db.ScanRow(ctx, rows, s); err != nil {
return nil, err
}
ss[s.Token] = s.Data
}
if err = rows.Close(); err != nil {
return nil, err
}
return ss, nil
}
func (b *BunStore) startCleanup(interval time.Duration) {
b.stopCleanup = make(chan bool)
ticker := time.NewTicker(interval)
for {
select {
case <-ticker.C:
err := b.deleteExpired()
if err != nil {
log.Println(err)
}
case <-b.stopCleanup:
ticker.Stop()
return
}
}
}
// StopCleanup terminates the background cleanup goroutine for the BunStore
// instance. It's rare to terminate this; generally BunStore instances and
// their cleanup goroutines are intended to be long-lived and run for the lifetime
// of your application.
//
// There may be occasions though when your use of the BunStore is transient.
// An example is creating a new BunStore instance in a test function. In this
// scenario, the cleanup goroutine (which will run forever) will prevent the
// BunStore object from being garbage collected even after the test function
// has finished. You can prevent this by manually calling StopCleanup.
func (b *BunStore) StopCleanup() {
if b.stopCleanup != nil {
b.stopCleanup <- true
}
}
func (b *BunStore) deleteExpired() error {
ctx := context.Background()
_, err := b.db.NewDelete().Model(&session{}).Where("expiry < ?", time.Now()).Exec(ctx)
if err != nil {
return err
}
return nil
}
// We have to add the plain Store methods here to be recognized a Store
// by the go compiler. Not using a seperate type makes any errors caught
// only at runtime instead of compile time. Oh well.
func (b *BunStore) Find(token string) ([]byte, bool, error) {
panic("missing context arg")
}
func (b *BunStore) Commit(token string, bb []byte, expiry time.Time) error {
panic("missing context arg")
}
func (b *BunStore) Delete(token string) error {
panic("missing context arg")
}