.

go/xcommon/xnet/lonet/registry_sqlite.go

@@ -74,8 +74,10 @@ func (r *sqliteRegistry) Close() (err error) {
 	return r.dbpool.Close()
 }
 
-func (r *sqliteRegistry) setup(ctx context.Context) (err error) {
-	// XXX dup
+// withConn runs f on a dbpool connection.
+//
+// connection is first allocated from dbpool and put back after call to f.
+func (r *sqliteRegistry) withConn(ctx context.Context, f func(*sqlite.Conn) error) error {
 	conn := r.dbpool.Get(ctx.Done())
 	if conn == nil {
 		// either ctx cancel or dbpool close
@@ -85,8 +87,12 @@ func (r *sqliteRegistry) setup(ctx context.Context) (err error) {
 		return errRegistryDown // db closed
 	}
 	defer r.dbpool.Put(conn)
+	return f(conn)
+}
 
-	err = sqliteutil.ExecScript(conn, `
+func (r *sqliteRegistry) setup(ctx context.Context) (err error) {
+	return r.withConn(ctx, func(conn *sqlite.Conn) error {
+		err := sqliteutil.ExecScript(conn, `
 			CREATE TABLE IF NOT EXISTS hosts (
 				hostname	TEXT NON NULL PRIMARY KEY,
 				osladdr		TEXT NON NULL
@@ -105,23 +111,16 @@ func (r *sqliteRegistry) setup(ctx context.Context) (err error) {
 		// XXX check network name
 
 		return nil
+	})
 }
 
 func (r *sqliteRegistry) Announce(ctx context.Context, hostname, osladdr string) (err error) {
 	defer r.regerr(&err, "announce", hostname, osladdr)
 
-	// XXX dup
-	conn := r.dbpool.Get(ctx.Done())
-	if conn == nil {
-		// either ctx cancel or dbpool close
-		if ctx.Err() != nil {
-			return ctx.Err()
-		}
-		return errRegistryDown // db closed
-	}
-	defer r.dbpool.Put(conn)
-
-	err = sqliteutil.Exec(conn, "INSERT INTO hosts (hostname, osladdr) VALUES (?, ?)", nil, hostname, osladdr)
+	return r.withConn(ctx, func(conn *sqlite.Conn) error {
+		err := sqliteutil.Exec(conn,
+			"INSERT INTO hosts (hostname, osladdr) VALUES (?, ?)", nil,
+			hostname, osladdr)
 
 		switch sqlite.ErrCode(err) {
 		case sqlite.SQLITE_CONSTRAINT_UNIQUE:	// XXX test
@@ -129,6 +128,7 @@ func (r *sqliteRegistry) Announce(ctx context.Context, hostname, osladdr string)
 		}
 
 		return err
+	})
 }
 
 var errRegDup = errors.New("registry broken: duplicate host entries")
@@ -136,35 +136,30 @@ var errRegDup = errors.New("registry broken: duplicate host entries")
 func (r *sqliteRegistry) Query(ctx context.Context, hostname string) (osladdr string, err error) {
 	defer r.regerr(&err, "query", hostname)
 
-	// XXX dup
-	conn := r.dbpool.Get(ctx.Done())
-	if conn == nil {
-		// either ctx cancel or dbpool close
-		if ctx.Err() != nil {
-			return "", ctx.Err()
-		}
-		return "", errRegistryDown // db closed
-	}
-	defer r.dbpool.Put(conn)
-
+	err = r.withConn(ctx, func(conn *sqlite.Conn) error {
 		nrow := 0
-	err = sqliteutil.Exec(conn, "SELECT osladdr FROM hosts WHERE hostname = ?", func (stmt *sqlite.Stmt) error {
+		err := sqliteutil.Exec(conn, "SELECT osladdr FROM hosts WHERE hostname = ?",
+			func (stmt *sqlite.Stmt) error {
 				osladdr = stmt.ColumnText(0)
 				nrow++
 				return nil
 			}, hostname)
 
 		if err != nil {
-		return "", err
+			return err
 		}
 
 		if nrow == 0 {
-		return "", errNoHost
+			return errNoHost
 		} else if nrow > 1 {
 			// hostname is PK - we should not get several results
-		return "", errRegDup
+			osladdr = ""
+			return errRegDup
 		}
 
+		return nil
+	})
+
 	return osladdr, err
 }
 

go/xcommon/xnet/lonet/registry_sqlite_test.go

@@ -42,7 +42,7 @@ func TestRegistrySQLite(t *testing.T) {
 	r, err := openRegistrySQLite(ctx, dbpath)
 	X(err)
 
-	// quert checks that result of Query(hostname) is as expect
+	// query checks that result of Query(hostname) is as expected.
 	//
 	// if expect is error - it checks that Query returns error with cause == expect.
 	// otherwise expect must be string and it will check that Query
@@ -54,7 +54,7 @@ func TestRegistrySQLite(t *testing.T) {
 		osladdr, err := r.Query(ctx, hostname)
 		if ewant, iserr := expect.(error); iserr {
 			// error expected
-			// XXX construct full registry error around ewant + reflect.DeepCompare
+			// XXX construct full registry error around ewant + reflect.DeepCompare?
 			e, ok := err.(*registryError)
 			if !(ok && e.Err == ewant && osladdr == "") {
 				t.Fatalf("%s: query %q:\nwant: \"\", %v\nhave: %q, %v",
@@ -70,7 +70,7 @@ func TestRegistrySQLite(t *testing.T) {
 		}
 	}
 
-	// announce checks that result of Announce(hostname, osladdr) is as expected
+	// announce checks that result of Announce(hostname, osladdr) is as expected.
 	//
 	// if len(errv) == 1 - it checks that Announce returns error with cause == errv[0].
 	// otherwise it will check that Announce succeeds and returns nil error.
@@ -86,7 +86,7 @@ func TestRegistrySQLite(t *testing.T) {
 		}
 		if ewant != nil {
 			// error expected
-			// XXX construct full registry error around ewant + reflect.DeepCompare
+			// XXX construct full registry error around ewant + reflect.DeepCompare?
 			e, ok := err.(*registryError)
 			if (!ok && e.Err == ewant) {
 				t.Fatalf("%s: announce %q %q:\nwant %v\nhave: %v",
@@ -128,5 +128,9 @@ func TestRegistrySQLite(t *testing.T) {
 	announce(r, "γ", "gamma:qqq", errRegistryDown)
 	query(r, "γ", errRegistryDown)
 
+	query(r2, "α", "alpha:1234")
+
 	X(r2.Close())
+
+	query(r2, "α", errRegistryDown)
 }