Butler: export Coordinator host in environment.

logdog/client/cmd/logdog_butler/main.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 (
         "bytes"
         "flag"
         "fmt"
@@ skipping 95 matching lines @@
 }
 
 func (a *application) authenticator(ctx context.Context) (*auth.Authenticator, error) {
         opts, err := a.authFlags.Options()
         if err != nil {
                 return nil, err
         }
         return auth.NewAuthenticator(ctx, auth.SilentLogin, opts), nil
 }
 
-func (a *application) configOutput() (output.Output, error) {
+// getOutputFactory returns the currently-configured output factory.
+func (a *application) getOutputFactory() (outputFactory, error) {
         factory := a.outputConfig.getFactory()
         if factory == nil {
                 return nil, errors.New("main: No output is configured")
         }
-
-        output, err := factory.configOutput(a)
-        if err != nil {
-                return nil, err
-        }
-
-        return output, nil
+        return factory, nil
 }
 
 // runWithButler is an execution harness that adds application-level management
 // to a Butler run.
 func (a *application) runWithButler(ctx context.Context, out output.Output,
         runFunc func(context.Context, *butler.Butler) error) error {
 
         // Enable CPU profiling if specified
         if a.cpuProfile != "" {
                 f, err := os.Create(a.cpuProfile)
@@ skipping 201 matching lines @@
 
         paniccatcher.Do(func() {
                 rc = mainImpl(ctx, os.Args[1:])
         }, func(p *paniccatcher.Panic) {
                 log.Fields{
                         "panic.error": p.Reason,
                 }.Errorf(ctx, "Panic caught in main:\n%s", p.Stack)
                 rc = runtimeErrorReturnCode
         })
 }