Add monitoring for expired ignore rules.

golden/go/skiacorrectness/main.go

 package main
 
 import (
         "encoding/json"
         "flag"
         "fmt"
         "io/ioutil"
         "net/http"
         "os"
         "path/filepath"
         "runtime/pprof"
         "time"
 
         "github.com/gorilla/mux"
+        "github.com/rcrowley/go-metrics"
         "github.com/skia-dev/glog"
         "go.skia.org/infra/go/auth"
         "go.skia.org/infra/go/common"
         "go.skia.org/infra/go/database"
         "go.skia.org/infra/go/login"
         "go.skia.org/infra/go/metadata"
         "go.skia.org/infra/go/redisutil"
         "go.skia.org/infra/go/skiaversion"
         "go.skia.org/infra/go/timer"
         "go.skia.org/infra/go/util"
@@ skipping 337 matching lines @@
         vdb := database.NewVersionedDB(conf)
 
         storages = &storage.Storage{
                 DiffStore:         diffStore,
                 ExpectationsStore: expstorage.NewCachingExpectationStore(expstorage.NewSQLExpectationStore(vdb)),
                 IgnoreStore:       ignore.NewSQLIgnoreStore(vdb),
                 TileStore:         filetilestore.NewFileTileStore(*tileStoreDir, pconfig.DATASET_GOLD, 2*time.Minute),
                 NCommits:          *nCommits,
         }
 
+        if err := ignore.StartMonitoring(storages.IgnoreStore, metrics.DefaultRegistry); err != nil {

[stephana, 2015/04/13 13:56:57]

How about calling this Init and setting the DefaultRegistry in the Init function
? So it would be something like this:

if err := ignore.Init(storages)
... 


It think that pattern is desirable when we are never going to have more than one
instance of a type in an app. 

[jcgregorio, 2015/04/13 14:10:59]

Done.

+                glog.Fatalf("Failed to start monitoring for expired ignore rules: %s", err)
+        }
+
         // Enable the experimental features.
         if *startExperimental {
                 tallies, err = tally.New(storages)
                 if err != nil {
                         glog.Fatalf("Failed to build tallies: %s", err)
                 }
 
                 summaries, err = summary.New(storages, tallies)
                 if err != nil {
                         glog.Fatalf("Failed to build summary: %s", err)
@@ skipping 59 matching lines @@
         // Everything else is served out of the static directory.
         router.PathPrefix("/").Handler(http.FileServer(http.Dir(*staticDir)))
 
         // Send all requests to the router
         http.Handle("/", util.LoggingGzipRequestResponse(router))
 
         // Start the server
         glog.Infoln("Serving on http://127.0.0.1" + *port)
         glog.Fatal(http.ListenAndServe(*port, nil))
 }