scheduler: add GetJobInvocations api.

scheduler/appengine/apiservers/scheduler.go

 // 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 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"
         "github.com/luci/luci-go/scheduler/appengine/presentation"
         "golang.org/x/net/context"
         "google.golang.org/grpc"
         "google.golang.org/grpc/codes"
+        "google.golang.org/grpc/status"
 )
 
 // SchedulerServer implements scheduler.Scheduler API.
 type SchedulerServer struct {
         Engine  engine.Engine
         Catalog catalog.Catalog
 }
 
 var _ scheduler.SchedulerServer = (*SchedulerServer)(nil)
 
@@ skipping 20 matching lines @@
                         Name:     ej.GetJobName(),
                         Project:  ej.ProjectID,
                         Schedule: ej.Schedule,
                         State: &scheduler.JobState{
                                 UiStatus: string(presentation.GetPublicStateKind(ej, traits)),
                         },
                 }
         }
         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
+}