Add context to cache API

pkg/client/cache/memory.go

@@ -15,6 +15,7 @@
 package cache
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"sync"
@@ -58,50 +59,55 @@ func NewMemoryCache() Cache {
 
 // Get returns cache from memory.
 // If non-existent or expired, return nil.
-func (bc *MemoryCache) Get(name string) interface{} {
+func (bc *MemoryCache) Get(ctx context.Context, key string) (interface{}, error) {
 	bc.RLock()
 	defer bc.RUnlock()
-	if itm, ok := bc.items[name]; ok {
+	if itm, ok := bc.items[key]; ok {
 		if itm.isExpire() {
-			return nil
+			return nil, errors.New("the key is expired")
 		}
-		return itm.val
+		return itm.val, nil
 	}
-	return nil
+	return nil, nil
 }
 
 // GetMulti gets caches from memory.
 // If non-existent or expired, return nil.
-func (bc *MemoryCache) GetMulti(names []string) []interface{} {
+func (bc *MemoryCache) GetMulti(ctx context.Context, keys []string) ([]interface{}, error) {
 	var rc []interface{}
-	for _, name := range names {
-		rc = append(rc, bc.Get(name))
+	for _, name := range keys {
+		val, err := bc.Get(context.Background(), name)
+		if err != nil {
+			rc = append(rc, err)
+		} else {
+			rc = append(rc, val)
+		}
 	}
-	return rc
+	return rc, nil
 }
 
 // Put puts cache into memory.
 // If lifespan is 0, it will never overwrite this value unless restarted
-func (bc *MemoryCache) Put(name string, value interface{}, lifespan time.Duration) error {
+func (bc *MemoryCache) Put(ctx context.Context, key string, val interface{}, timeout time.Duration) error {
 	bc.Lock()
 	defer bc.Unlock()
-	bc.items[name] = &MemoryItem{
-		val:         value,
+	bc.items[key] = &MemoryItem{
+		val:         val,
 		createdTime: time.Now(),
-		lifespan:    lifespan,
+		lifespan:    timeout,
 	}
 	return nil
 }
 
 // Delete cache in memory.
-func (bc *MemoryCache) Delete(name string) error {
+func (bc *MemoryCache) Delete(ctx context.Context, key string) error {
 	bc.Lock()
 	defer bc.Unlock()
-	if _, ok := bc.items[name]; !ok {
+	if _, ok := bc.items[key]; !ok {
 		return errors.New("key not exist")
 	}
-	delete(bc.items, name)
-	if _, ok := bc.items[name]; ok {
+	delete(bc.items, key)
+	if _, ok := bc.items[key]; ok {
 		return errors.New("delete key error")
 	}
 	return nil
@@ -109,7 +115,7 @@ func (bc *MemoryCache) Delete(name string) error {
 
 // Incr increases cache counter in memory.
 // Supports int,int32,int64,uint,uint32,uint64.
-func (bc *MemoryCache) Incr(key string) error {
+func (bc *MemoryCache) Incr(ctx context.Context, key string) error {
 	bc.Lock()
 	defer bc.Unlock()
 	itm, ok := bc.items[key]
@@ -136,7 +142,7 @@ func (bc *MemoryCache) Incr(key string) error {
 }
 
 // Decr decreases counter in memory.
-func (bc *MemoryCache) Decr(key string) error {
+func (bc *MemoryCache) Decr(ctx context.Context, key string) error {
 	bc.Lock()
 	defer bc.Unlock()
 	itm, ok := bc.items[key]
@@ -175,17 +181,17 @@ func (bc *MemoryCache) Decr(key string) error {
 }
 
 // IsExist checks if cache exists in memory.
-func (bc *MemoryCache) IsExist(name string) bool {
+func (bc *MemoryCache) IsExist(ctx context.Context, key string) (bool, error) {
 	bc.RLock()
 	defer bc.RUnlock()
-	if v, ok := bc.items[name]; ok {
-		return !v.isExpire()
+	if v, ok := bc.items[key]; ok {
+		return !v.isExpire(), nil
 	}
-	return false
+	return false, nil
 }
 
 // ClearAll deletes all cache in memory.
-func (bc *MemoryCache) ClearAll() error {
+func (bc *MemoryCache) ClearAll(context.Context) error {
 	bc.Lock()
 	defer bc.Unlock()
 	bc.items = make(map[string]*MemoryItem)