package client import ( "context" "encoding/json" "fmt" "hash/fnv" "time" cache "github.com/patrickmn/go-cache" "github.com/unistack-org/micro/v3/metadata" ) // NewCache returns an initialised cache. func NewCache() *Cache { return &Cache{ cache: cache.New(cache.NoExpiration, 30*time.Second), } } // Cache for responses type Cache struct { cache *cache.Cache } // Get a response from the cache func (c *Cache) Get(ctx context.Context, req Request) (interface{}, bool) { return c.cache.Get(key(ctx, req)) } // Set a response in the cache func (c *Cache) Set(ctx context.Context, req Request, rsp interface{}, expiry time.Duration) { c.cache.Set(key(ctx, req), rsp, expiry) } // List the key value pairs in the cache func (c *Cache) List() map[string]string { items := c.cache.Items() rsp := make(map[string]string, len(items)) for k, v := range items { bytes, _ := json.Marshal(v.Object) rsp[k] = string(bytes) } return rsp } // key returns a hash for the context and request func key(ctx context.Context, req Request) string { ns, _ := metadata.Get(ctx, "Micro-Namespace") bytes, _ := json.Marshal(map[string]interface{}{ "namespace": ns, "request": map[string]interface{}{ "service": req.Service(), "endpoint": req.Endpoint(), "method": req.Method(), "body": req.Body(), }, }) h := fnv.New64() h.Write(bytes) return fmt.Sprintf("%x", h.Sum(nil)) }