Butler: export Coordinator host in environment.

logdog/client/cmd/logdog_butler/output_logdog.go

 // Copyright 2015 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 main
 
 import (
         "time"
 
         "github.com/luci/luci-go/common/clock/clockflag"
         "github.com/luci/luci-go/common/errors"
         "github.com/luci/luci-go/common/flag/multiflag"
         "github.com/luci/luci-go/logdog/client/butler/output"
         out "github.com/luci/luci-go/logdog/client/butler/output/logdog"
 )
 
 func init() {
         registerOutputFactory(new(logdogOutputFactory))
 }
 
+type coordinatorHostOutput interface {
+        getCoordinatorHost() string
+}
+
 // logdogOutputFactory for publishing logs using a LogDog Coordinator host.
 type logdogOutputFactory struct {
         host             string
         prefixExpiration clockflag.Duration
 
         track bool
 }
 
 var _ outputFactory = (*logdogOutputFactory)(nil)
 
@@ skipping 28 matching lines @@
                 PrefixExpiration: time.Duration(f.prefixExpiration),
                 SourceInfo: []string{
                         "LogDog Butler",
                 },
                 PublishContext: a.ncCtx,
                 Track:          f.track,
         }
         return cfg.Register(a)
 }
 
-func (f *logdogOutputFactory) scopes() []string { return out.Scopes() }
+func (f *logdogOutputFactory) scopes() []string           { return out.Scopes() }
+func (f *logdogOutputFactory) getCoordinatorHost() string { return f.host }