scheduler: add GetJobInvocations api.

scheduler/appengine/apiservers/scheduler.go

Index: scheduler/appengine/apiservers/scheduler.go
diff --git a/scheduler/appengine/apiservers/scheduler.go b/scheduler/appengine/apiservers/scheduler.go
index 6cece118514558ea222f8dc80b621eb35cd63771..cf2f5a8669feb099e9af2dea7e3ffc15208e860e 100644
--- a/scheduler/appengine/apiservers/scheduler.go
+++ b/scheduler/appengine/apiservers/scheduler.go
@@ -5,6 +5,7 @@
 package apiservers
 
 import (
+	"github.com/luci/luci-go/common/clock"
 	"github.com/luci/luci-go/scheduler/api/scheduler/v1"
 	"github.com/luci/luci-go/scheduler/appengine/catalog"
 	"github.com/luci/luci-go/scheduler/appengine/engine"
@@ -12,6 +13,7 @@ import (
 	"golang.org/x/net/context"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 )
 
 // SchedulerServer implements scheduler.Scheduler API.
@@ -52,3 +54,46 @@ func (s SchedulerServer) GetJobs(ctx context.Context, in *scheduler.JobsRequest)
 	}
 	return &scheduler.JobsReply{Jobs: jobs}, nil
 }
+
+func (s SchedulerServer) GetInvocations(ctx context.Context, in *scheduler.InvocationsRequest) (*scheduler.InvocationsReply, error) {
+	ejob, err := s.Engine.GetJob(ctx, in.GetProject()+"/"+in.GetJob())
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "datastore error: %s", err)

[Vadim Sh., 2017/06/21 23:46:41]

we don't support 'status'

use grpc.Errorf(...)

[tandrii(chromium), 2017/06/22 15:47:42]

https://godoc.org/google.golang.org/grpc#Errorf says it is deprecated and that I
should status.Errorf instead, and in fact grpc.Errorf just calls into
status.Errorf anyway.

[Vadim Sh., 2017/06/22 17:06:25]

well.. I now for sure that pRPC implementation ignores any rich structure of
'status' replies, so we should just use grpc.Errorf for now, before anyone tries
to use unsupported status fields.

[tandrii(chromium), 2017/06/22 17:44:17]

OK, changed back. Now I wonder: is returning codes.NotFound (below) OK or should
I have a separate field in reply message for this case?

+	}
+	if ejob == nil {
+		return nil, status.Error(codes.NotFound, "Job does not exist or you have no access")
+	}
+
+	pageSize := 50

[Vadim Sh., 2017/06/21 23:46:41]

note in proto that 50 is default and maximum

[tandrii(chromium), 2017/06/22 15:47:42]

Done. I don't have a good way to choose the maximum; 50 is what UI uses today.

+	if in.PageSize > 0 && int(in.PageSize) < pageSize {
+		pageSize = int(in.PageSize)
+	}
+
+	nowTs := clock.Now(ctx).UnixNano() / 1000
+	einvs, cursor, err := s.Engine.ListInvocations(ctx, ejob.JobID, pageSize, in.GetCursor())
+	if err != nil {
+		return nil, grpc.Errorf(codes.Internal, "datastore error: %s", err)
+	}
+	invs := make([]*scheduler.Invocation, len(einvs))
+	for i, einv := range einvs {
+		invs[i] = &scheduler.Invocation{
+			Id:             einv.ID,
+			Job:            ejob.GetJobName(),
+			Project:        ejob.ProjectID,
+			StartedTs:      einv.Started.UnixNano() / 1000,
+			TriggeredBy:    string(einv.TriggeredBy),
+			Status:         string(einv.Status),
+			Final:          einv.Status.Final(),
+			ConfigRevision: einv.Revision,
+			ViewUrl:        einv.ViewURL,
+		}
+		if einv.Status.Final() {
+			invs[i].FinishedTs = einv.Finished.UnixNano() / 1000
+		}
+	}
+	return &scheduler.InvocationsReply{
+		Invocations: invs,
+		NextCursor:  cursor,
+		NowTs:       nowTs,
+	}, nil
+}