feat: allow disabling cache

americanas-tech · Sep 15, 2021 · a5e38aa · a5e38aa
1 parent 82cb42e
commit a5e38aa
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Showing 3 changed files with 34 additions and 10 deletions.
diff --git a/docs/restql/config.md b/docs/restql/config.md
@@ -109,7 +109,7 @@ RestQL uses cache to avoid excessive database calls and grammar parsing. The cac
 
 For fetching mappings from the database restQL uses a stale-cache strategy, which runs an update task in background when the TTL for an entry expire and only replace the cached value if the fetching is successful. This allows restQL to stay updated but not break if the database goes offline.
 
-You can customize each cache maximum size and, for the mappings cache, other parameters.
+You can customize each cache maximum size and, for the mappings cache, other parameters. You can also disable all caching using `cache.disable: true` or `RESTQL_CACHE_DISABLE=true`.
 
 **Queries and Parser**
 

diff --git a/internal/platform/conf/conf.go b/internal/platform/conf/conf.go
@@ -93,6 +93,8 @@ type Config struct {
 	} `yaml:"logging"`
 
 	Cache struct {
+		Disable bool `yaml:"disable" env:"RESTQL_CACHE_DISABLE"`
+
 		Mappings struct {
 			MaxSize            int           `yaml:"maxSize" env:"RESTQL_CACHE_MAPPINGS_MAX_SIZE"`
 			Expiration         time.Duration `yaml:"expiration" env:"RESTQL_CACHE_MAPPINGS_EXPIRATION"`

diff --git a/internal/platform/web/routes.go b/internal/platform/web/routes.go
@@ -48,17 +48,10 @@ func API(log restql.Logger, cfg *conf.Config) (fasthttp.RequestHandler, error) {
 	})
 
 	mappingReader := persistence.NewMappingReader(log, cfg.Env, cfg.TenantMappings, db)
-	tenantCache := cache.New(log, cfg.Cache.Mappings.MaxSize,
-		cache.TenantCacheLoader(mappingReader),
-		cache.WithExpiration(cfg.Cache.Mappings.Expiration),
-		cache.WithRefreshInterval(cfg.Cache.Mappings.RefreshInterval),
-		cache.WithRefreshQueueLength(cfg.Cache.Mappings.RefreshQueueLength),
-	)
-	cacheMr := cache.NewMappingsReaderCache(log, tenantCache)
+	cacheMr := addMappingsReaderCache(log, cfg, mappingReader)
 
 	queryReader := persistence.NewQueryReader(log, cfg.Queries, db)
-	queryCache := cache.New(log, cfg.Cache.Query.MaxSize, cache.QueryCacheLoader(queryReader))
-	cacheQr := cache.NewQueryReaderCache(log, queryCache)
+	cacheQr := addQueryReaderCache(log, cfg, queryReader)
 
 	e := eval.NewEvaluator(log, cacheMr, cacheQr, r, parserCache, lifecycle)
 
@@ -83,6 +76,35 @@ func API(log restql.Logger, cfg *conf.Config) (fasthttp.RequestHandler, error) {
 	return app.RequestHandler(), nil
 }
 
+func addMappingsReaderCache(log restql.Logger, cfg *conf.Config, mappingReader persistence.MappingsReader) eval.MappingsReader {
+	if cfg.Cache.Disable {
+		return mappingReader
+	}
+
+	log.Info("mappings cache enabled")
+
+	tenantCache := cache.New(log, cfg.Cache.Mappings.MaxSize,
+		cache.TenantCacheLoader(mappingReader),
+		cache.WithExpiration(cfg.Cache.Mappings.Expiration),
+		cache.WithRefreshInterval(cfg.Cache.Mappings.RefreshInterval),
+		cache.WithRefreshQueueLength(cfg.Cache.Mappings.RefreshQueueLength),
+	)
+	cacheMr := cache.NewMappingsReaderCache(log, tenantCache)
+	return cacheMr
+}
+
+func addQueryReaderCache(log restql.Logger, cfg *conf.Config, queryReader persistence.QueryReader) eval.QueryReader {
+	if cfg.Cache.Disable {
+		return queryReader
+	}
+
+	log.Info("queries cache enabled")
+
+	queryCache := cache.New(log, cfg.Cache.Query.MaxSize, cache.QueryCacheLoader(queryReader))
+	cacheQr := cache.NewQueryReaderCache(log, queryCache)
+	return cacheQr
+}
+
 // registerAdminEndpoints adds handlers for administrative operations
 func registerAdminEndpoints(adm *administrator, apiApp app) app {
 	apiApp.Handle(http.MethodGet, "/admin/tenant", adm.AllTenants)