feat(eviction): make mapping keys eviction interval configurable

Add `mapping_eviction_interval` configuration option to control how often
the mapping keys eviction coroutine runs. Defaults to 1 minute (preserving
current behavior).

Changes:
- Add MappingEvictionInterval field to DefaultCache config
- Replace time.Sleep with time.After for channel-based waiting
- Move timing logic from EvictMapping to registerMappingKeysEviction

Usage:
  default_cache:
    mapping_eviction_interval: 6h

Author: cdaguerre

configurationtypes/types.go

@@ -279,6 +279,7 @@ type DefaultCache struct {
 	DefaultCacheControl          string        `json:"default_cache_control" yaml:"default_cache_control"`
 	MaxBodyBytes                 uint64        `json:"max_cacheable_body_bytes" yaml:"max_cacheable_body_bytes"`
 	DisableCoalescing            bool          `json:"disable_coalescing" yaml:"disable_coalescing"`
+	MappingEvictionInterval      Duration      `json:"mapping_eviction_interval" yaml:"mapping_eviction_interval"`
 }
 
 // GetAllowedHTTPVerbs returns the allowed verbs to cache
@@ -401,6 +402,14 @@ func (d *DefaultCache) IsCoalescingDisable() bool {
 	return d.DisableCoalescing
 }
 
+// GetMappingEvictionInterval returns the interval for mapping eviction
+func (d *DefaultCache) GetMappingEvictionInterval() time.Duration {
+	if d.MappingEvictionInterval.Duration == 0 {
+		return time.Minute
+	}
+	return d.MappingEvictionInterval.Duration
+}
+
 // DefaultCacheInterface interface
 type DefaultCacheInterface interface {
 	GetAllowedHTTPVerbs() []string
@@ -427,6 +436,7 @@ type DefaultCacheInterface interface {
 	GetDefaultCacheControl() string
 	GetMaxBodyBytes() uint64
 	IsCoalescingDisable() bool
+	GetMappingEvictionInterval() time.Duration
 }
 
 // APIEndpoint is the minimal structure to define an endpoint

pkg/api/souin.go

@@ -199,7 +199,6 @@ func EvictMapping(current types.Storer) {
 			current.Delete(core.MappingKeyPrefix + k)
 		}
 	}
-	time.Sleep(time.Minute)
 }
 
 func (s *SouinAPI) purgeMapping() {

pkg/middleware/middleware.go

@@ -92,9 +92,9 @@ func tryAcquireEvictionLock(storer types.Storer) bool {
 	return string(verifyValue) == lockValue
 }
 
-func registerMappingKeysEviction(logger core.Logger, storers []types.Storer) {
+func registerMappingKeysEviction(logger core.Logger, storers []types.Storer, interval time.Duration) {
 	for _, storer := range storers {
-		logger.Debugf("registering mapping eviction for storer %s", storer.Name())
+		logger.Debugf("registering mapping eviction for storer %s (interval: %s)", storer.Name(), interval)
 		go func(current types.Storer) {
 			for {
 				if !tryAcquireEvictionLock(current) {
@@ -105,6 +105,7 @@ func registerMappingKeysEviction(logger core.Logger, storers []types.Storer) {
 
 				logger.Debugf("run mapping eviction for storer %s", current.Name())
 				api.EvictMapping(current)
+				<-time.After(interval)
 			}
 		}(storer)
 	}
@@ -198,7 +199,7 @@ func NewHTTPCacheHandler(c configurationtypes.AbstractConfigurationInterface) *S
 	}
 	c.GetLogger().Info("Souin configuration is now loaded.")
 
-	registerMappingKeysEviction(c.GetLogger(), storers)
+	registerMappingKeysEviction(c.GetLogger(), storers, c.GetDefaultCache().GetMappingEvictionInterval())
 
 	return &SouinBaseHandler{
 		Configuration:            c,