Initial distributor implementation

appengine/cmd/dm/mutate/activate_execution.go

Index: appengine/cmd/dm/mutate/activate_execution.go
diff --git a/appengine/cmd/dm/mutate/activate_execution.go b/appengine/cmd/dm/mutate/activate_execution.go
new file mode 100644
index 0000000000000000000000000000000000000000..3dcc93040af6b395cac9bc1ee03ac92c9491bec9
--- /dev/null
+++ b/appengine/cmd/dm/mutate/activate_execution.go
@@ -0,0 +1,39 @@
+// 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 mutate
+
+import (
+	"golang.org/x/net/context"
+
+	"github.com/luci/gae/service/datastore"
+	"github.com/luci/luci-go/appengine/cmd/dm/model"
+	"github.com/luci/luci-go/appengine/tumble"
+	"github.com/luci/luci-go/common/api/dm/service/v1"
+)
+
+// ActivateExecution executes an execution, moving it from the
+// SCHEDULING->RUNNING state, and resetting the execution timeout (if any).
+type ActivateExecution struct {
+	Auth   *dm.Execution_Auth
+	NewTok []byte
+}
+
+// Root implements tumble.Mutation.
+func (a *ActivateExecution) Root(c context.Context) *datastore.Key {
+	return model.AttemptKeyFromID(c, a.Auth.Id.AttemptID())
+}
+
+// RollForward implements tumble.Mutation
+func (a *ActivateExecution) RollForward(c context.Context) (muts []tumble.Mutation, err error) {
+	_, e, err := model.ActivateExecution(c, a.Auth, a.NewTok)
+	if err == nil {
+		err = ResetExecutionTimeout(c, e)
+	}
+	return
+}
+
+func init() {
+	tumble.Register((*ActivateExecution)(nil))
+}