From 02d04e1387daea2daa65bd675da0be9b418bfcf8 Mon Sep 17 00:00:00 2001
From: nobe4 <nobe4@users.noreply.github.com>
Date: Sat, 28 Sep 2024 19:11:04 +0200
Subject: [PATCH] feat(cache): move the expiration logic out (#179)

---
 internal/cache/cache.go     | 32 +++++++++++++++-----------------
 internal/gh/gh.go           |  4 ++--
 internal/manager/manager.go | 10 ++++++----
 3 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/internal/cache/cache.go b/internal/cache/cache.go
index d885883..1b4be4b 100644
--- a/internal/cache/cache.go
+++ b/internal/cache/cache.go
@@ -1,3 +1,10 @@
+/*
+Package cache provides a simple file-based cache implementation that fullfills
+the RefreshReadWriter interface.
+
+It writes and reads the cache to a file in JSON format, along with the last
+refresh time.
+*/
 package cache
 
 import (
@@ -9,17 +16,15 @@ import (
 	"time"
 )
 
-type ExpiringReadWriter interface {
+type RefreshReadWriter interface {
 	Read(any) error
 	Write(any) error
-	Expired() bool
+	Refresh(time.Time)
 	RefreshedAt() time.Time
-	SetRefreshedAt(time.Time)
 }
 
 type FileCache struct {
 	path string
-	ttl  time.Duration
 	wrap *CacheWrap
 }
 
@@ -28,11 +33,8 @@ type CacheWrap struct {
 	RefreshedAt time.Time `json:"refreshed_at"`
 }
 
-func NewFileCache(ttlInHours int, path string) *FileCache {
-	return &FileCache{
-		path: path,
-		ttl:  time.Duration(ttlInHours) * time.Hour,
-	}
+func NewFileCache(path string) *FileCache {
+	return &FileCache{path: path}
 }
 
 func (c *FileCache) Read(out any) error {
@@ -61,20 +63,16 @@ func (c *FileCache) Read(out any) error {
 	return err
 }
 
-func (c *FileCache) RefreshedAt() time.Time {
-	return c.wrap.RefreshedAt
-}
-
-func (c *FileCache) SetRefreshedAt(t time.Time) {
+func (c *FileCache) Refresh(t time.Time) {
 	c.wrap.RefreshedAt = t
 }
 
-func (c *FileCache) Expired() bool {
-	return time.Now().After(c.RefreshedAt().Add(c.ttl))
+func (c *FileCache) RefreshedAt() time.Time {
+	return c.wrap.RefreshedAt
 }
 
 func (c *FileCache) deprecatedRead(content []byte) error {
-	slog.Warn("Cache is in an deprecated format. Attempting to read from the old format.")
+	slog.Warn("Cache is in an format deprecated in v0.5.0. Attempting to read from the old format.")
 
 	if err := json.Unmarshal(content, c.wrap.Data); err != nil {
 		return err
diff --git a/internal/gh/gh.go b/internal/gh/gh.go
index f97d26b..a644edd 100644
--- a/internal/gh/gh.go
+++ b/internal/gh/gh.go
@@ -30,13 +30,13 @@ var (
 
 type Client struct {
 	API      api.Requestor
-	cache    cache.ExpiringReadWriter
+	cache    cache.RefreshReadWriter
 	maxRetry int
 	maxPage  int
 	url      string
 }
 
-func NewClient(api api.Requestor, cache cache.ExpiringReadWriter, config config.Endpoint) *Client {
+func NewClient(api api.Requestor, cache cache.RefreshReadWriter, config config.Endpoint) *Client {
 	url := DefaultUrl
 
 	query := url.Query()
diff --git a/internal/manager/manager.go b/internal/manager/manager.go
index 8d1dd21..b66c3a8 100644
--- a/internal/manager/manager.go
+++ b/internal/manager/manager.go
@@ -16,7 +16,7 @@ import (
 
 type Manager struct {
 	Notifications notifications.Notifications
-	Cache         cache.ExpiringReadWriter
+	Cache         cache.RefreshReadWriter
 	config        *config.Data
 	client        *gh.Client
 	Actions       actions.ActionsMap
@@ -29,7 +29,7 @@ func New(config *config.Data) *Manager {
 	m := &Manager{}
 
 	m.config = config
-	m.Cache = cache.NewFileCache(m.config.Cache.TTLInHours, m.config.Cache.Path)
+	m.Cache = cache.NewFileCache(m.config.Cache.Path)
 
 	return m
 }
@@ -50,7 +50,9 @@ func (m *Manager) Load() error {
 }
 
 func (m *Manager) Refresh() error {
-	if m.RefreshStrategy.ShouldRefresh(m.Cache.Expired()) {
+	expired := time.Now().After(m.Cache.RefreshedAt().Add(time.Duration(m.config.Cache.TTLInHours) * time.Hour))
+
+	if m.RefreshStrategy.ShouldRefresh(expired) {
 		return m.refreshNotifications()
 	}
 
@@ -75,7 +77,7 @@ func (m *Manager) refreshNotifications() error {
 	m.Notifications = m.Notifications.Uniq()
 	m.Notifications, err = m.Enrich(m.Notifications)
 
-	m.Cache.SetRefreshedAt(time.Now())
+	m.Cache.Refresh(time.Now())
 
 	return err
 }