Initial distributor implementation

appengine/cmd/dm/model/quest.go

Index: appengine/cmd/dm/model/quest.go
diff --git a/appengine/cmd/dm/model/quest.go b/appengine/cmd/dm/model/quest.go
index d16f0a97e418bd57d0cc2315ae4391a5bfa36134..318704e230516522a7261770c22975060ffd7eb1 100644
--- a/appengine/cmd/dm/model/quest.go
+++ b/appengine/cmd/dm/model/quest.go
@@ -5,59 +5,23 @@
 package model
 
 import (
-	"crypto/sha256"
-	"encoding/base64"
-	"fmt"
 	"time"
 
-	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/context"
 
 	"github.com/luci/gae/service/datastore"
 	"github.com/luci/luci-go/common/clock"
 	google_pb "github.com/luci/luci-go/common/proto/google"
 
-	"github.com/luci/luci-go/common/api/dm/service/v1"
-	"github.com/luci/luci-go/common/api/template"
-)
-
-var (
-	// QuestIDLength is the number of encoded bytes to use. It removes the
-	// single padding character.
-	QuestIDLength = base64.URLEncoding.EncodedLen(sha256.Size) - 1
-)
-
-const (
-	// payloadMaxLength is the maximum size of the Quest Desc
-	payloadMaxLength = 256 * 1024
+	dm "github.com/luci/luci-go/common/api/dm/service/v1"
 )
 
 // NewQuest builds a new Quest object with a correct ID given the current
 // contents of the Quest_Desc. It returns an error if the Desc is invalid.
 //
-// This will also compactify the inner json Desc as a side effect.
-func NewQuest(c context.Context, desc *dm.Quest_Desc) (ret *Quest, err error) {
-	if len(desc.JsonPayload) > payloadMaxLength {
-		return nil, fmt.Errorf("quest payload is too large: %d > %d",
-			len(desc.JsonPayload), payloadMaxLength)
-	}
-	desc.JsonPayload, err = template.NormalizeJSON(desc.JsonPayload, true)
-	if err != nil {
-		return
-	}
-
-	data, err := proto.Marshal(desc)
-	if err != nil {
-		panic(err)
-	}
-	h := sha256.Sum256(data)
-
-	ret = &Quest{
-		ID:      base64.URLEncoding.EncodeToString(h[:])[:QuestIDLength],
-		Desc:    *desc,
-		Created: clock.Now(c).UTC(),
-	}
-	return
+// Desc must already be Normalize()'d
+func NewQuest(c context.Context, desc *dm.Quest_Desc) *Quest {

[dnj (Google), 2016/06/09 18:00:56]

It might not be a bad idea to omit "c" here and supply "now" externally. At
worst this causes the same amount of work, and at best it makes this function
purely operations on data and allows "Now" to be called fewer times if the
caller already gets it. Just a thought.

[iannucci, 2016/06/15 00:46:01]

I think I like the context better: the fact that we extract the current time is
an implementation detail of model.Quest, not a function of the caller. If there
were multiple permissible values to pass for the time value, then I think it
would make sense, but in this case it does not. Requiring users to call
NewQuest(clock.Now(c), desc) feels wrong to me.

+	return &Quest{ID: desc.QuestID(), Desc: *desc, Created: clock.Now(c).UTC()}
 }
 
 // Quest is the model for a job-to-run. Its questPayload should fully