Make the rest of the services have a similar raw/user interface structure.

impl/prod/taskqueue.go

Index: impl/prod/taskqueue.go
diff --git a/impl/prod/taskqueue.go b/impl/prod/taskqueue.go
index 815db3a734145680ba995038c483442aa57f604a..ce0f443dfb528cef53fa566de815775f899f5b65 100644
--- a/impl/prod/taskqueue.go
+++ b/impl/prod/taskqueue.go
@@ -9,15 +9,15 @@ import (
 	"reflect"
 
 	tq "github.com/luci/gae/service/taskqueue"
-	"github.com/luci/luci-go/common/errors"
 	"golang.org/x/net/context"
+	"google.golang.org/appengine"
 	"google.golang.org/appengine/taskqueue"
 )
 
 // useTQ adds a gae.TaskQueue implementation to context, accessible
 // by gae.GetTQ(c)
 func useTQ(c context.Context) context.Context {
-	return tq.SetFactory(c, func(ci context.Context) tq.Interface {
+	return tq.SetRawFactory(c, func(ci context.Context) tq.RawInterface {
 		return tqImpl{ci}
 	})
 }
@@ -43,11 +43,10 @@ func init() {
 	}
 }
 
-// tqR2FErr (TQ real-to-fake w/ error) converts a *taskqueue.Task to a
-// *tq.Task, and passes through an error.
-func tqR2FErr(o *taskqueue.Task, err error) (*tq.Task, error) {
-	if err != nil {
-		return nil, err
+// tqR2F (TQ real-to-fake) converts a *taskqueue.Task to a *tq.Task.
+func tqR2F(o *taskqueue.Task) *tq.Task {
+	if o == nil {
+		return nil
 	}
 	n := tq.Task{}
 	n.Path = o.Path
@@ -59,7 +58,7 @@ func tqR2FErr(o *taskqueue.Task, err error) (*tq.Task, error) {
 	n.ETA = o.ETA
 	n.RetryCount = o.RetryCount
 	n.RetryOptions = (*tq.RetryOptions)(o.RetryOptions)
-	return &n, nil
+	return &n
 }
 
 // tqF2R (TQ fake-to-real) converts a *tq.Task to a *taskqueue.Task.
@@ -77,19 +76,6 @@ func tqF2R(n *tq.Task) *taskqueue.Task {
 	return &o
 }
 
-// tqMR2FErr (TQ multi-real-to-fake w/ error) converts a slice of
-// *taskqueue.Task to a slice of *tq.Task
-func tqMR2FErr(os []*taskqueue.Task, err error) ([]*tq.Task, error) {
-	if err != nil {
-		return nil, errors.Fix(err)
-	}
-	ret := make([]*tq.Task, len(os))
-	for i, t := range os {
-		ret[i], _ = tqR2FErr(t, nil)
-	}
-	return ret, nil
-}
-
 // tqMF2R (TQ multi-fake-to-real) converts []*tq.Task to []*taskqueue.Task.
 func tqMF2R(ns []*tq.Task) []*taskqueue.Task {
 	ret := make([]*taskqueue.Task, len(ns))
@@ -99,52 +85,49 @@ func tqMF2R(ns []*tq.Task) []*taskqueue.Task {
 	return ret
 }
 
-//////// TQSingleReadWriter
-
-func (t tqImpl) Add(task *tq.Task, queueName string) (*tq.Task, error) {
-	return tqR2FErr(taskqueue.Add(t.Context, tqF2R(task), queueName))
-}
-func (t tqImpl) Delete(task *tq.Task, queueName string) error {
-	return taskqueue.Delete(t.Context, tqF2R(task), queueName)
-}
-
-//////// TQMultiReadWriter
-
-func (t tqImpl) AddMulti(tasks []*tq.Task, queueName string) ([]*tq.Task, error) {
-	return tqMR2FErr(taskqueue.AddMulti(t.Context, tqMF2R(tasks), queueName))
-}
-func (t tqImpl) DeleteMulti(tasks []*tq.Task, queueName string) error {
-	return errors.Fix(taskqueue.DeleteMulti(t.Context, tqMF2R(tasks), queueName))
+func (t tqImpl) AddMulti(tasks []*tq.Task, queueName string, cb tq.RawTaskCB) error {
+	realTasks, err := taskqueue.AddMulti(t.Context, tqMF2R(tasks), queueName)
+	if err != nil {
+		if me, ok := err.(appengine.MultiError); ok {
+			for i, err := range me {
+				tsk := (*taskqueue.Task)(nil)
+				if realTasks != nil {
+					tsk = realTasks[i]
+				}
+				cb(tqR2F(tsk), err)
+			}
+			err = nil
+		}
+	} else {
+		for _, tsk := range realTasks {
+			cb(tqR2F(tsk), nil)
+		}
+	}
+	return err
 }
 
-//////// TQLeaser
-
-func (t tqImpl) Lease(maxTasks int, queueName string, leaseTime int) ([]*tq.Task, error) {
-	return tqMR2FErr(taskqueue.Lease(t.Context, maxTasks, queueName, leaseTime))
-}
-func (t tqImpl) LeaseByTag(maxTasks int, queueName string, leaseTime int, tag string) ([]*tq.Task, error) {
-	return tqMR2FErr(taskqueue.LeaseByTag(t.Context, maxTasks, queueName, leaseTime, tag))
-}
-func (t tqImpl) ModifyLease(task *tq.Task, queueName string, leaseTime int) error {
-	return taskqueue.ModifyLease(t.Context, tqF2R(task), queueName, leaseTime)
+func (t tqImpl) DeleteMulti(tasks []*tq.Task, queueName string, cb tq.RawCB) error {
+	err := taskqueue.DeleteMulti(t.Context, tqMF2R(tasks), queueName)
+	if me, ok := err.(appengine.MultiError); ok {
+		for _, err := range me {
+			cb(err)
+		}
+		err = nil
+	}
+	return err
 }
 
-//////// TQPurger
-
 func (t tqImpl) Purge(queueName string) error {
 	return taskqueue.Purge(t.Context, queueName)
 }
 
-//////// TQStatter
-
-func (t tqImpl) QueueStats(queueNames []string) ([]tq.Statistics, error) {
+func (t tqImpl) Stats(queueNames []string, cb tq.RawStatsCB) error {
 	stats, err := taskqueue.QueueStats(t.Context, queueNames)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	ret := make([]tq.Statistics, len(stats))
-	for i, s := range stats {
-		ret[i] = tq.Statistics(s)
+	for _, s := range stats {
+		cb((*tq.Statistics)(&s), nil)
 	}
-	return ret, nil
+	return nil
 }