snapstate: move refresh hints handling into its own struct

overlord/snapstate/refreshhints.go

@@ -0,0 +1,70 @@
+// -*- Mode: Go; indent-tabs-mode: t -*-
+
+/*
+ * Copyright (C) 2017 Canonical Ltd
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package snapstate
+
+import (
+	"time"
+
+	"github.com/snapcore/snapd/overlord/state"
+	"github.com/snapcore/snapd/store"
+)
+
+var refreshHintsDelay = time.Duration(24 * time.Hour)
+
+type refreshHints struct {
+	state *state.State
+}
+
+func newRefreshHints(st *state.State) *refreshHints {
+	return &refreshHints{state: st}
+}
+
+func (r *refreshHints) lastRefresh() (time.Time, error) {
+	var lastRefresh time.Time
+	if err := r.state.Get("last-refresh-hints", &lastRefresh); err != nil && err != state.ErrNoState {
+		return time.Time{}, err
+	}
+	return lastRefresh, nil
+}
+
+func (r *refreshHints) needsUpdate() (bool, error) {
+	t, err := r.lastRefresh()
+	if err != nil {
+		return false, err
+	}
+	return t.Before(time.Now().Add(-refreshHintsDelay)), nil
+}
+
+func (r *refreshHints) refresh() error {
+	_, _, _, err := refreshCandidates(r.state, nil, nil, &store.RefreshOptions{RefreshManaged: true})
+	r.state.Set("last-refresh-hints", time.Now())
+	return err
+}
+
+func (r *refreshHints) Ensure() error {
+	needsUpdate, err := r.needsUpdate()
+	if err != nil {
+		return err
+	}
+	if !needsUpdate {
+		return nil
+	}
+	return r.refresh()
+}

overlord/snapstate/snapmgr.go

@@ -79,6 +79,8 @@ type SnapManager struct {
 	nextRefresh            time.Time
 	lastRefreshAttempt     time.Time
 
+	refreshHints *refreshHints
+
 	nextCatalogRefresh time.Time
 
 	lastUbuntuCoreTransitionAttempt time.Time
@@ -300,9 +302,10 @@ func Manager(st *state.State) (*SnapManager, error) {
 	runner := state.NewTaskRunner(st)
 
 	m := &SnapManager{
-		state:   st,
-		backend: backend.Backend{},
-		runner:  runner,
+		state:        st,
+		backend:      backend.Backend{},
+		runner:       runner,
+		refreshHints: newRefreshHints(st),
 	}
 
 	if err := os.MkdirAll(dirs.SnapCookieDir, 0700); err != nil {
@@ -516,23 +519,6 @@ func (m *SnapManager) NextCatalogRefresh() time.Time {
 	return m.nextCatalogRefresh
 }
 
-// checkRefreshHints will check for refrehes every 24h regardless of the
-// refresh schedule to be able to provide hints about outdated packages
-// to the user once we have the warning system in place.
-func (m *SnapManager) checkRefreshHints() error {
-	var lastRefreshHints time.Time
-	if err := m.state.Get("last-refresh-hints", &lastRefreshHints); err != nil && err != state.ErrNoState {
-		return err
-	}
-	if lastRefreshHints.Before(time.Now().Add(-time.Duration(24 * time.Hour))) {
-		if _, _, _, err := refreshCandidates(m.state, nil, nil, &store.RefreshOptions{RefreshManaged: true}); err != nil {
-			return err
-		}
-		m.state.Set("last-refresh-hints", time.Now())
-	}
-	return nil
-}
-
 // ensureRefreshes ensures that we refresh all installed snaps periodically
 func (m *SnapManager) ensureRefreshes() error {
 	m.state.Lock()
@@ -547,7 +533,7 @@ func (m *SnapManager) ensureRefreshes() error {
 	}
 
 	// always check refresh hints
-	m.checkRefreshHints()
+	m.refreshHints.Ensure()
 
 	// get lastRefresh and schedule
 	lastRefresh, err := m.LastRefresh()