diff options
Diffstat (limited to 'vendor/golang.org/x/net/context/context.go')
| -rw-r--r-- | vendor/golang.org/x/net/context/context.go | 114 |
1 files changed, 7 insertions, 107 deletions
diff --git a/vendor/golang.org/x/net/context/context.go b/vendor/golang.org/x/net/context/context.go index 134654cf7e..a3c021d3f8 100644 --- a/vendor/golang.org/x/net/context/context.go +++ b/vendor/golang.org/x/net/context/context.go @@ -5,9 +5,11 @@ // Package context defines the Context type, which carries deadlines, // cancelation signals, and other request-scoped values across API boundaries // and between processes. +// As of Go 1.7 this package is available in the standard library under the +// name context. https://golang.org/pkg/context. // // Incoming requests to a server should create a Context, and outgoing calls to -// servers should accept a Context. The chain of function calls between must +// servers should accept a Context. The chain of function calls between must // propagate the Context, optionally replacing it with a modified copy created // using WithDeadline, WithTimeout, WithCancel, or WithValue. // @@ -16,14 +18,14 @@ // propagation: // // Do not store Contexts inside a struct type; instead, pass a Context -// explicitly to each function that needs it. The Context should be the first +// explicitly to each function that needs it. The Context should be the first // parameter, typically named ctx: // // func DoSomething(ctx context.Context, arg Arg) error { // // ... use ctx ... // } // -// Do not pass a nil Context, even if a function permits it. Pass context.TODO +// Do not pass a nil Context, even if a function permits it. Pass context.TODO // if you are unsure about which Context to use. // // Use context Values only for request-scoped data that transits processes and @@ -36,112 +38,15 @@ // Contexts. package context // import "golang.org/x/net/context" -import "time" - -// A Context carries a deadline, a cancelation signal, and other values across -// API boundaries. -// -// Context's methods may be called by multiple goroutines simultaneously. -type Context interface { - // Deadline returns the time when work done on behalf of this context - // should be canceled. Deadline returns ok==false when no deadline is - // set. Successive calls to Deadline return the same results. - Deadline() (deadline time.Time, ok bool) - - // Done returns a channel that's closed when work done on behalf of this - // context should be canceled. Done may return nil if this context can - // never be canceled. Successive calls to Done return the same value. - // - // WithCancel arranges for Done to be closed when cancel is called; - // WithDeadline arranges for Done to be closed when the deadline - // expires; WithTimeout arranges for Done to be closed when the timeout - // elapses. - // - // Done is provided for use in select statements: - // - // // Stream generates values with DoSomething and sends them to out - // // until DoSomething returns an error or ctx.Done is closed. - // func Stream(ctx context.Context, out chan<- Value) error { - // for { - // v, err := DoSomething(ctx) - // if err != nil { - // return err - // } - // select { - // case <-ctx.Done(): - // return ctx.Err() - // case out <- v: - // } - // } - // } - // - // See http://blog.golang.org/pipelines for more examples of how to use - // a Done channel for cancelation. - Done() <-chan struct{} - - // Err returns a non-nil error value after Done is closed. Err returns - // Canceled if the context was canceled or DeadlineExceeded if the - // context's deadline passed. No other values for Err are defined. - // After Done is closed, successive calls to Err return the same value. - Err() error - - // Value returns the value associated with this context for key, or nil - // if no value is associated with key. Successive calls to Value with - // the same key returns the same result. - // - // Use context values only for request-scoped data that transits - // processes and API boundaries, not for passing optional parameters to - // functions. - // - // A key identifies a specific value in a Context. Functions that wish - // to store values in Context typically allocate a key in a global - // variable then use that key as the argument to context.WithValue and - // Context.Value. A key can be any type that supports equality; - // packages should define keys as an unexported type to avoid - // collisions. - // - // Packages that define a Context key should provide type-safe accessors - // for the values stores using that key: - // - // // Package user defines a User type that's stored in Contexts. - // package user - // - // import "golang.org/x/net/context" - // - // // User is the type of value stored in the Contexts. - // type User struct {...} - // - // // key is an unexported type for keys defined in this package. - // // This prevents collisions with keys defined in other packages. - // type key int - // - // // userKey is the key for user.User values in Contexts. It is - // // unexported; clients use user.NewContext and user.FromContext - // // instead of using this key directly. - // var userKey key = 0 - // - // // NewContext returns a new Context that carries value u. - // func NewContext(ctx context.Context, u *User) context.Context { - // return context.WithValue(ctx, userKey, u) - // } - // - // // FromContext returns the User value stored in ctx, if any. - // func FromContext(ctx context.Context) (*User, bool) { - // u, ok := ctx.Value(userKey).(*User) - // return u, ok - // } - Value(key interface{}) interface{} -} - // Background returns a non-nil, empty Context. It is never canceled, has no -// values, and has no deadline. It is typically used by the main function, +// values, and has no deadline. It is typically used by the main function, // initialization, and tests, and as the top-level Context for incoming // requests. func Background() Context { return background } -// TODO returns a non-nil, empty Context. Code should use context.TODO when +// TODO returns a non-nil, empty Context. Code should use context.TODO when // it's unclear which Context to use or it is not yet available (because the // surrounding function has not yet been extended to accept a Context // parameter). TODO is recognized by static analysis tools that determine @@ -149,8 +54,3 @@ func Background() Context { func TODO() Context { return todo } - -// A CancelFunc tells an operation to abandon its work. -// A CancelFunc does not wait for the work to stop. -// After the first call, subsequent calls to a CancelFunc do nothing. -type CancelFunc func() |