type Group struct {
// contains filtered or unexported fields
}
Group represents a class of work and forms a namespace in which units of work can be executed with duplicate suppression.
func (g *Group) Do(key string, fn func() (interface{}, error)) (v interface{}, err error, shared bool)
Do executes and returns the results of the given function, making sure that only one execution is in-flight for a given key at a time. If a duplicate comes in, the duplicate caller waits for the original to complete and receives the same results. The return value shared indicates whether v was given to multiple callers.
func (g *Group) DoChan(key string, fn func() (interface{}, error)) (<-chan Result, bool)
DoChan is like Do but returns a channel that will receive the results when they are ready. The second result is true if the function will eventually be called, false if it will not (because there is a pending request with this key).
func (g *Group) ForgetUnshared(key string) bool
ForgetUnshared tells the singleflight to forget about a key if it is not shared with any other goroutines. Future calls to Do for a forgotten key will call the function rather than waiting for an earlier call to complete. Returns whether the key was forgotten or unknown--that is, whether no other goroutines are waiting for the result.
type Result struct {
Val interface{}
Err error
Shared bool
}
Result holds the results of Do, so they can be passed on a channel.