ctxutil

Documentation

Index

• func NewReader(ctx context.Context, r io.Reader) *ctxReader
• func NewWriter(ctx context.Context, w io.Writer) *ctxWriter
• func WithDeadlineFraction(ctx context.Context, fraction float64) (context.Context, context.CancelFunc)
• type Reader
• type Writer

Functions

func NewReader

func NewReader(ctx context.Context, r io.Reader) *ctxReader

NewReader wraps a reader to make it respect given Context. If there is a blocking read, the returned Reader will return whenever the context is cancelled (the return values are n=0 and err=ctx.Err().)

Note well: this wrapper DOES NOT ACTUALLY cancel the underlying write-- there is no way to do that with the standard go io interface. So the read and write _will_ happen or hang. So, use this sparingly, make sure to cancel the read or write as necesary (e.g. closing a connection whose context is up, etc.)

Furthermore, in order to protect your memory from being read _before_ you've cancelled the context, this io.Reader will allocate a buffer of the same size, and **copy** into the client's if the read succeeds in time.

func NewWriter

func NewWriter(ctx context.Context, w io.Writer) *ctxWriter

NewWriter wraps a writer to make it respect given Context. If there is a blocking write, the returned Writer will return whenever the context is cancelled (the return values are n=0 and err=ctx.Err().)

Note well: this wrapper DOES NOT ACTUALLY cancel the underlying write-- there is no way to do that with the standard go io interface. So the read and write _will_ happen or hang. So, use this sparingly, make sure to cancel the read or write as necesary (e.g. closing a connection whose context is up, etc.)

Furthermore, in order to protect your memory from being read _after_ you've cancelled the context, this io.Writer will first make a **copy** of the buffer.

func WithDeadlineFraction

func WithDeadlineFraction(ctx context.Context, fraction float64) (context.Context, context.CancelFunc)

Types

type Reader

type Reader interface {
	io.Reader
}

type Writer

type Writer interface {
	io.Writer
}