Implementation of cacheable by tx hash methods (#66)

* Implementation of cacheable by tx hash methods

* Update CACHING.md

.env

@@ -127,6 +127,7 @@ REDIS_PASSWORD=
 CACHE_METHOD_HAS_BLOCK_NUMBER_PARAM_TTL_SECONDS=600
 CACHE_METHOD_HAS_BLOCK_HASH_PARAM_TTL_SECONDS=600
 CACHE_STATIC_METHOD_TTL_SECONDS=600
+CACHE_METHOD_HAS_TX_HASH_PARAM_TTL_SECONDS=600
 # CACHE_PREFIX is used as prefix for any key in the cache, key has such structure:
 # <cache_prefix>:evm-request:<method_name>:sha256:<sha256(body)>
 # Possible values are testnet, mainnet, etc...

architecture/CACHING.md

@@ -38,6 +38,7 @@ As of now we have 3 different groups of cacheable EVM methods:
 - cacheable by block number (for ex.: `eth_getBlockByNumber`)
 - cacheable by block hash (for ex.: `eth_getBlockByHash`)
 - static methods (for ex.: `eth_chainId`, `net_version`)
+- cacheable by tx hash (for ex.: `eth_getTransactionReceipt`)
 
 ### Cacheable by block number
 
@@ -86,6 +87,14 @@ For example:
 {"jsonrpc":"2.0","method":"net_version","params":[],"id":67}
 ```
 
+### Cacheable by tx hash
+
+Cacheable by tx hash means that for specific:
+- method
+- params
+- tx hash (which is part of params)
+response won't change over time, so we can cache it indefinitely
+
 ### Where to find list of methods for every group?
 
 It can be found in source code: https://github.com/Kava-Labs/kava-proxy-service/blob/main/decode/evm_rpc.go

config/config.go

@@ -50,6 +50,7 @@ type Config struct {
 	CacheMethodHasBlockNumberParamTTL             time.Duration
 	CacheMethodHasBlockHashParamTTL               time.Duration
 	CacheStaticMethodTTL                          time.Duration
+	CacheMethodHasTxHashParamTTL                  time.Duration
 	CachePrefix                                   string
 	WhitelistedHeaders                            []string
 	DefaultAccessControlAllowOriginValue          string
@@ -114,6 +115,7 @@ const (
 	CACHE_METHOD_HAS_BLOCK_NUMBER_PARAM_TTL_ENVIRONMENT_KEY           = "CACHE_METHOD_HAS_BLOCK_NUMBER_PARAM_TTL_SECONDS"
 	CACHE_METHOD_HAS_BLOCK_HASH_PARAM_TTL_ENVIRONMENT_KEY             = "CACHE_METHOD_HAS_BLOCK_HASH_PARAM_TTL_SECONDS"
 	CACHE_STATIC_METHOD_TTL_ENVIRONMENT_KEY                           = "CACHE_STATIC_METHOD_TTL_SECONDS"
+	CACHE_METHOD_HAS_TX_HASH_PARAM_TTL_ENVIRONMENT_KEY                = "CACHE_METHOD_HAS_TX_HASH_PARAM_TTL_SECONDS"
 	CACHE_PREFIX_ENVIRONMENT_KEY                                      = "CACHE_PREFIX"
 	WHITELISTED_HEADERS_ENVIRONMENT_KEY                               = "WHITELISTED_HEADERS"
 	DEFAULT_ACCESS_CONTROL_ALLOW_ORIGIN_VALUE_ENVIRONMENT_KEY         = "DEFAULT_ACCESS_CONTROL_ALLOW_ORIGIN_VALUE"
@@ -307,6 +309,7 @@ func ReadConfig() Config {
 		CacheMethodHasBlockNumberParamTTL:             time.Duration(EnvOrDefaultInt(CACHE_METHOD_HAS_BLOCK_NUMBER_PARAM_TTL_ENVIRONMENT_KEY, 0)) * time.Second,
 		CacheMethodHasBlockHashParamTTL:               time.Duration(EnvOrDefaultInt(CACHE_METHOD_HAS_BLOCK_HASH_PARAM_TTL_ENVIRONMENT_KEY, 0)) * time.Second,
 		CacheStaticMethodTTL:                          time.Duration(EnvOrDefaultInt(CACHE_STATIC_METHOD_TTL_ENVIRONMENT_KEY, 0)) * time.Second,
+		CacheMethodHasTxHashParamTTL:                  time.Duration(EnvOrDefaultInt(CACHE_METHOD_HAS_TX_HASH_PARAM_TTL_ENVIRONMENT_KEY, 0)) * time.Second,
 		CachePrefix:                                   os.Getenv(CACHE_PREFIX_ENVIRONMENT_KEY),
 		WhitelistedHeaders:                            parsedWhitelistedHeaders,
 		DefaultAccessControlAllowOriginValue:          os.Getenv(DEFAULT_ACCESS_CONTROL_ALLOW_ORIGIN_VALUE_ENVIRONMENT_KEY),

config/validate.go

@@ -75,6 +75,9 @@ func Validate(config Config) error {
 	if err := checkTTLConfig(config.CacheStaticMethodTTL, CACHE_STATIC_METHOD_TTL_ENVIRONMENT_KEY); err != nil {
 		allErrs = errors.Join(allErrs, err)
 	}
+	if err := checkTTLConfig(config.CacheMethodHasTxHashParamTTL, CACHE_METHOD_HAS_TX_HASH_PARAM_TTL_ENVIRONMENT_KEY); err != nil {
+		allErrs = errors.Join(allErrs, err)
+	}
 
 	if strings.Contains(config.CachePrefix, ":") {
 		allErrs = errors.Join(allErrs, fmt.Errorf("invalid %s specified %s, must not contain colon symbol", CACHE_PREFIX_ENVIRONMENT_KEY, config.CachePrefix))

decode/evm_rpc.go

@@ -106,6 +106,24 @@ func IsMethodStatic(method string) bool {
 	return false
 }
 
+// CacheableByTxHashMethods is a list of EVM methods which can be cached indefinitely by transaction hash.
+// It means that for specific method and params (which includes tx hash) response will never change.
+var CacheableByTxHashMethods = []string{
+	"eth_getTransactionReceipt",
+	"eth_getTransactionByHash",
+}
+
+// MethodHasTxHashParam checks if method is cacheable by tx hash.
+func MethodHasTxHashParam(method string) bool {
+	for _, cacheableByTxHashMethod := range CacheableByTxHashMethods {
+		if method == cacheableByTxHashMethod {
+			return true
+		}
+	}
+
+	return false
+}
+
 // NoHistoryMethods is a list of JSON-RPC methods that rely only on the present state of the chain.
 // They can always be safely routed to an up-to-date pruning cluster.
 var NoHistoryMethods = []string{

service/cachemdw/cache.go

@@ -19,6 +19,7 @@ type Config struct {
 	CacheMethodHasBlockNumberParamTTL time.Duration
 	CacheMethodHasBlockHashParamTTL   time.Duration
 	CacheStaticMethodTTL              time.Duration
+	CacheMethodHasTxHashParamTTL      time.Duration
 }
 
 // ServiceCache is responsible for caching EVM requests and provides corresponding middleware
@@ -115,6 +116,10 @@ func IsCacheable(
 		return true
 	}
 
+	if decode.MethodHasTxHashParam(req.Method) {
+		return true
+	}
+
 	return false
 }
 
@@ -132,6 +137,10 @@ func (c *ServiceCache) GetTTL(method string) (time.Duration, error) {
 		return c.config.CacheStaticMethodTTL, nil
 	}
 
+	if decode.MethodHasTxHashParam(method) {
+		return c.config.CacheMethodHasTxHashParamTTL, nil
+	}
+
 	return 0, ErrRequestIsNotCacheable
 }
 

service/cachemdw/cache_test.go

@@ -28,6 +28,7 @@ var (
 		CacheMethodHasBlockNumberParamTTL: time.Hour,
 		CacheMethodHasBlockHashParamTTL:   time.Hour,
 		CacheStaticMethodTTL:              time.Hour,
+		CacheMethodHasTxHashParamTTL:      time.Hour,
 	}
 )
 

service/service.go

@@ -211,6 +211,7 @@ func createServiceCache(
 		CacheMethodHasBlockNumberParamTTL: config.CacheMethodHasBlockNumberParamTTL,
 		CacheMethodHasBlockHashParamTTL:   config.CacheMethodHasBlockHashParamTTL,
 		CacheStaticMethodTTL:              config.CacheStaticMethodTTL,
+		CacheMethodHasTxHashParamTTL:      config.CacheMethodHasTxHashParamTTL,
 	}
 
 	serviceCache := cachemdw.NewServiceCache(