package cache import ( "sync" "github.com/ReneKroon/ttlcache" "github.com/sirupsen/logrus" "github.com/superseriousbusiness/gotosocial/internal/gtsmodel" ) // AccountCache is a wrapper around ttlcache.Cache to provide URL and URI lookups for gtsmodel.Account type AccountCache struct { cache *ttlcache.Cache // map of IDs -> cached accounts urls map[string]string // map of account URLs -> IDs uris map[string]string // map of account URIs -> IDs mutex sync.Mutex } // NewAccountCache returns a new instantiated AccountCache object func NewAccountCache() *AccountCache { c := AccountCache{ cache: ttlcache.NewCache(), urls: make(map[string]string, 100), uris: make(map[string]string, 100), mutex: sync.Mutex{}, } // Set callback to purge lookup maps on expiration c.cache.SetExpirationCallback(func(key string, value interface{}) { account, ok := value.(*gtsmodel.Account) if !ok { logrus.Panicf("AccountCache could not assert entry with key %s to *gtsmodel.Account", key) } c.mutex.Lock() delete(c.urls, account.URL) delete(c.uris, account.URI) c.mutex.Unlock() }) return &c } // GetByID attempts to fetch a account from the cache by its ID, you will receive a copy for thread-safety func (c *AccountCache) GetByID(id string) (*gtsmodel.Account, bool) { c.mutex.Lock() account, ok := c.getByID(id) c.mutex.Unlock() return account, ok } // GetByURL attempts to fetch a account from the cache by its URL, you will receive a copy for thread-safety func (c *AccountCache) GetByURL(url string) (*gtsmodel.Account, bool) { // Perform safe ID lookup c.mutex.Lock() id, ok := c.urls[url] // Not found, unlock early if !ok { c.mutex.Unlock() return nil, false } // Attempt account lookup account, ok := c.getByID(id) c.mutex.Unlock() return account, ok } // GetByURI attempts to fetch a account from the cache by its URI, you will receive a copy for thread-safety func (c *AccountCache) GetByURI(uri string) (*gtsmodel.Account, bool) { // Perform safe ID lookup c.mutex.Lock() id, ok := c.uris[uri] // Not found, unlock early if !ok { c.mutex.Unlock() return nil, false } // Attempt account lookup account, ok := c.getByID(id) c.mutex.Unlock() return account, ok } // getByID performs an unsafe (no mutex locks) lookup of account by ID, returning a copy of account in cache func (c *AccountCache) getByID(id string) (*gtsmodel.Account, bool) { v, ok := c.cache.Get(id) if !ok { return nil, false } a, ok := v.(*gtsmodel.Account) if !ok { panic("account cache entry was not an account") } return copyAccount(a), true } // Put places a account in the cache, ensuring that the object place is a copy for thread-safety func (c *AccountCache) Put(account *gtsmodel.Account) { if account == nil || account.ID == "" { panic("invalid account") } c.mutex.Lock() c.cache.Set(account.ID, copyAccount(account)) if account.URL != "" { c.urls[account.URL] = account.ID } if account.URI != "" { c.uris[account.URI] = account.ID } c.mutex.Unlock() } // copyAccount performs a surface-level copy of account, only keeping attached IDs intact, not the objects. // due to all the data being copied being 99% primitive types or strings (which are immutable and passed by ptr) // this should be a relatively cheap process func copyAccount(account *gtsmodel.Account) *gtsmodel.Account { return >smodel.Account{ ID: account.ID, Username: account.Username, Domain: account.Domain, AvatarMediaAttachmentID: account.AvatarMediaAttachmentID, AvatarMediaAttachment: nil, AvatarRemoteURL: account.AvatarRemoteURL, HeaderMediaAttachmentID: account.HeaderMediaAttachmentID, HeaderMediaAttachment: nil, HeaderRemoteURL: account.HeaderRemoteURL, DisplayName: account.DisplayName, Fields: account.Fields, Note: account.Note, Memorial: account.Memorial, MovedToAccountID: account.MovedToAccountID, CreatedAt: account.CreatedAt, UpdatedAt: account.UpdatedAt, Bot: account.Bot, Reason: account.Reason, Locked: account.Locked, Discoverable: account.Discoverable, Privacy: account.Privacy, Sensitive: account.Sensitive, Language: account.Language, URI: account.URI, URL: account.URL, LastWebfingeredAt: account.LastWebfingeredAt, InboxURI: account.InboxURI, OutboxURI: account.OutboxURI, FollowingURI: account.FollowingURI, FollowersURI: account.FollowersURI, FeaturedCollectionURI: account.FeaturedCollectionURI, ActorType: account.ActorType, AlsoKnownAs: account.AlsoKnownAs, PrivateKey: account.PrivateKey, PublicKey: account.PublicKey, PublicKeyURI: account.PublicKeyURI, SensitizedAt: account.SensitizedAt, SilencedAt: account.SilencedAt, SuspendedAt: account.SuspendedAt, HideCollections: account.HideCollections, SuspensionOrigin: account.SuspensionOrigin, } }