X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/41b9b83812826b77034fe13ea34047e194b1027f..064df2d66faf61f475813863e5c29ca07ad9555a:/lib/boot/rails_db.go

diff --git a/lib/boot/rails_db.go b/lib/boot/rails_db.go
index 3f81511445..16e150172d 100644
--- a/lib/boot/rails_db.go
+++ b/lib/boot/rails_db.go
@@ -13,6 +13,7 @@ import (
 
 	"git.arvados.org/arvados.git/lib/controller/dblock"
 	"git.arvados.org/arvados.git/lib/ctrlctx"
+	"github.com/sirupsen/logrus"
 )
 
 type railsDatabase struct{}
@@ -21,6 +22,10 @@ func (runner railsDatabase) String() string {
 	return "railsDatabase"
 }
 
+// Run checks for and applies any pending Rails database migrations.
+//
+// If running a dev/test environment, and the database is empty, it
+// initializes the database.
 func (runner railsDatabase) Run(ctx context.Context, fail func(error), super *Supervisor) error {
 	err := super.wait(ctx, runPostgreSQL{}, installPassenger{src: "services/api"})
 	if err != nil {
@@ -35,14 +40,18 @@ func (runner railsDatabase) Run(ctx context.Context, fail func(error), super *Su
 		appdir = filepath.Join(super.SourcePath, "services/api")
 	}
 
-	// list versions in db/migrate/{version}_{name}.rb
-	todo := map[string]bool{}
-	fs.WalkDir(os.DirFS(appdir), "db/migrate", func(path string, d fs.DirEntry, err error) error {
-		if cut := strings.Index(d.Name(), "_"); cut > 0 && strings.HasSuffix(d.Name(), ".rb") {
-			todo[d.Name()[:cut]] = true
-		}
-		return nil
-	})
+	// Check for pending migrations before running rake.
+	//
+	// In principle, we could use "rake db:migrate:status" or skip
+	// this check entirely and let "rake db:migrate" be a no-op
+	// most of the time.  However, in the most common case when
+	// there are no new migrations, that would add ~2s to startup
+	// time / downtime during service restart.
+
+	todo, err := migrationList(appdir, super.logger)
+	if err != nil {
+		return err
+	}
 
 	// read schema_migrations table (list of migrations already
 	// applied) and remove those entries from todo
@@ -87,3 +96,37 @@ func (runner railsDatabase) Run(ctx context.Context, fail func(error), super *Su
 	defer dblock.RailsMigrations.Unlock()
 	return super.RunProgram(ctx, appdir, runOptions{env: railsEnv}, "bundle", "exec", "rake", "db:migrate")
 }
+
+func migrationList(dir string, log logrus.FieldLogger) (map[string]bool, error) {
+	todo := map[string]bool{}
+
+	// list versions in db/migrate/{version}_{name}.rb
+	err := fs.WalkDir(os.DirFS(dir), "db/migrate", func(path string, d fs.DirEntry, err error) error {
+		if d.IsDir() {
+			return nil
+		}
+		fnm := d.Name()
+		if !strings.HasSuffix(fnm, ".rb") {
+			log.Warnf("unexpected file in db/migrate dir: %s", fnm)
+			return nil
+		}
+		for i, c := range fnm {
+			if i > 0 && c == '_' {
+				todo[fnm[:i]] = true
+				break
+			}
+			if c < '0' || c > '9' {
+				// non-numeric character before the
+				// first '_' means this is not a
+				// migration
+				log.Warnf("unexpected file in db/migrate dir: %s", fnm)
+				return nil
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	return todo, nil
+}