Butler stream servers can generate client address.

logdog/client/butlerlib/streamclient/local.go

-// Copyright 2016 The LUCI Authors. All rights reserved.
-// Use of this source code is governed under the Apache License, Version 2.0
-// that can be found in the LICENSE file.
-
-package streamclient
-
-import (
-        "io"
-
-        "github.com/luci/luci-go/logdog/client/butler"
-        "github.com/luci/luci-go/logdog/client/butlerlib/streamproto"
-)
-
-// localClient is a Client implementation that is directly bound to a Butler
-// instance.
-type localClient struct {
-        *butler.Butler
-}
-
-// NewLocal creates a new Client instance bound to a local Butler instance. This
-// sidesteps the need for an actual server socket and negotiation protocol and
-// directly registers streams via Butler API calls.
-//
-// Internally, the Stream uses an io.PipeWriter and io.PipeReader to ferry
-// data from the Stream's owner to the Butler.
-func NewLocal(b *butler.Butler) Client {
-        return &localClient{b}
-}
-
-func (c *localClient) NewStream(f streamproto.Flags) (s Stream, err error) {
-        pr, pw := io.Pipe()
-        defer func() {
-                if err != nil {
-                        pr.Close()
-                        pw.Close()
-                }
-        }()
-
-        props := f.Properties()
-        stream := streamImpl{
-                WriteCloser: pw,
-                props:       props,
-        }
-
-        // Add the Stream to the Butler.
-        if err = c.AddStream(pr, props); err != nil {
-                return
-        }
-        return &stream, nil
-}