proxy cancellations to mempool when useMempool is configured (#159)

Author: TymKh

cmd/server/main.go

@@ -29,6 +29,7 @@ var (
 	defaultServiceName              = os.Getenv("SERVICE_NAME")
 	defaultFetchInfoIntervalSeconds = 600
 	defaultRpcTTLCacheSeconds       = 300
+	defaultMempoolRPC               = os.Getenv("DEFAULT_MEMPOOL_RPC")
 
 	// cli flags
 	versionPtr           = flag.Bool("version", false, "just print the program version")
@@ -119,6 +120,7 @@ func main() {
 		BuilderInfoSource:   *builderInfoSource,
 		FetchInfoInterval:   *fetchIntervalSeconds,
 		TTLCacheSeconds:     int64(*ttlCacheSeconds),
+		DefaultMempoolRPC:   defaultMempoolRPC,
 	})
 	if err != nil {
 		logger.Crit("Server init error", "error", err)

go.mod

@@ -18,20 +18,28 @@ require (
 )
 
 require (
+	github.com/Microsoft/go-winio v0.6.2 // indirect
+	github.com/StackExchange/wmi v1.2.1 // indirect
 	github.com/bits-and-blooms/bitset v1.10.0 // indirect
 	github.com/btcsuite/btcd/btcec/v2 v2.2.0 // indirect
 	github.com/btcsuite/btcd/chaincfg/chainhash v1.0.1 // indirect
 	github.com/consensys/bavard v0.1.13 // indirect
 	github.com/consensys/gnark-crypto v0.12.1 // indirect
 	github.com/crate-crypto/go-kzg-4844 v1.0.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/deckarep/golang-set/v2 v2.6.0 // indirect
 	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1 // indirect
 	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
 	github.com/ethereum/c-kzg-4844 v1.0.0 // indirect
+	github.com/go-ole/go-ole v1.3.0 // indirect
+	github.com/gorilla/websocket v1.4.2 // indirect
 	github.com/holiman/uint256 v1.3.0 // indirect
 	github.com/mmcloughlin/addchain v0.4.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/shirou/gopsutil v3.21.4-0.20210419000835-c7a38de76ee5+incompatible // indirect
 	github.com/supranational/blst v0.3.11 // indirect
+	github.com/tklauser/go-sysconf v0.3.12 // indirect
+	github.com/tklauser/numcpus v0.6.1 // indirect
 	golang.org/x/sync v0.7.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	rsc.io/tmplfunc v0.0.3 // indirect

go.sum

@@ -1,5 +1,7 @@
 github.com/DataDog/zstd v1.4.5 h1:EndNeuB0l9syBZhut0wns3gV1hL8zX8LIu6ZiVHWLIQ=
 github.com/DataDog/zstd v1.4.5/go.mod h1:1jcaCB/ufaK+sKp1NBhlGmpz41jOoPQ35bpF36t7BBo=
+github.com/Microsoft/go-winio v0.6.2 h1:F2VQgta7ecxGYO8k3ZZz3RS8fVIXVxONVUPlNERoyfY=
+github.com/Microsoft/go-winio v0.6.2/go.mod h1:yd8OoFMLzJbo9gZq8j5qaps8bJ9aShtEA8Ipt1oGCvU=
 github.com/StackExchange/wmi v1.2.1 h1:VIkavFPXSjcnS+O8yTq7NI32k0R5Aj+v39y29VYDOSA=
 github.com/StackExchange/wmi v1.2.1/go.mod h1:rcmrprowKIVzvc+NUiLncP2uuArMWLCbu9SBzvHz7e8=
 github.com/VictoriaMetrics/fastcache v1.12.2 h1:N0y9ASrJ0F6h0QaC3o6uJb3NIZ9VKLjCM7NQbSmF7WI=
@@ -37,13 +39,17 @@ github.com/consensys/bavard v0.1.13 h1:oLhMLOFGTLdlda/kma4VOJazblc7IM5y5QPd2A/Yj
 github.com/consensys/bavard v0.1.13/go.mod h1:9ItSMtA/dXMAiL7BG6bqW2m3NdSEObYWoH223nGHukI=
 github.com/consensys/gnark-crypto v0.12.1 h1:lHH39WuuFgVHONRl3J0LRBtuYdQTumFSDtJF7HpyG8M=
 github.com/consensys/gnark-crypto v0.12.1/go.mod h1:v2Gy7L/4ZRosZ7Ivs+9SfUDr0f5UlG+EM5t7MPHiLuY=
+github.com/cpuguy83/go-md2man/v2 v2.0.2 h1:p1EgwI/C7NhT0JmVkwCD2ZBK8j4aeHQX2pMHHBfMQ6w=
+github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
 github.com/crate-crypto/go-ipa v0.0.0-20240223125850-b1e8a79f509c h1:uQYC5Z1mdLRPrZhHjHxufI8+2UG/i25QG92j0Er9p6I=
 github.com/crate-crypto/go-ipa v0.0.0-20240223125850-b1e8a79f509c/go.mod h1:geZJZH3SzKCqnz5VT0q/DyIG/tvu/dZk+VIfXicupJs=
 github.com/crate-crypto/go-kzg-4844 v1.0.0 h1:TsSgHwrkTKecKJ4kadtHi4b3xHW5dCFUDFnUp1TsawI=
 github.com/crate-crypto/go-kzg-4844 v1.0.0/go.mod h1:1kMhvPgI0Ky3yIa+9lFySEBUBXkYxeOi8ZF1sYioxhc=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/deckarep/golang-set/v2 v2.6.0 h1:XfcQbWM1LlMB8BsJ8N9vW5ehnnPVIw0je80NsVHagjM=
+github.com/deckarep/golang-set/v2 v2.6.0/go.mod h1:VAky9rY/yGXJOLEDv3OMci+7wtDpOF4IN+y82NBOac4=
 github.com/decred/dcrd/crypto/blake256 v1.0.0 h1:/8DMNYp9SGi5f0w7uCm6d6M4OU2rGFK09Y2A4Xv7EE0=
 github.com/decred/dcrd/crypto/blake256 v1.0.0/go.mod h1:sQl2p6Y26YV+ZOcSTP6thNdn47hh8kt6rqSlvmrXFAc=
 github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1 h1:YLtO71vCjJRCBcrPMtQ9nqBsqpA1m5sE92cU+pd5Mcc=
@@ -56,10 +62,15 @@ github.com/ethereum/go-ethereum v1.14.7 h1:EHpv3dE8evQmpVEQ/Ne2ahB06n2mQptdwqaMN
 github.com/ethereum/go-ethereum v1.14.7/go.mod h1:Mq0biU2jbdmKSZoqOj29017ygFrMnB5/Rifwp980W4o=
 github.com/ethereum/go-verkle v0.1.1-0.20240306133620-7d920df305f0 h1:KrE8I4reeVvf7C1tm8elRjj4BdscTYzz/WAbYyf/JI4=
 github.com/ethereum/go-verkle v0.1.1-0.20240306133620-7d920df305f0/go.mod h1:D9AJLVXSyZQXJQVk8oh1EwjISE+sJTn2duYIZC0dy3w=
+github.com/fjl/memsize v0.0.2 h1:27txuSD9or+NZlnOWdKUxeBzTAUkWCVh+4Gf2dWFOzA=
+github.com/fjl/memsize v0.0.2/go.mod h1:VvhXpOYNQvB+uIk2RvXzuaQtkQJzzIx6lSBe1xv7hi0=
 github.com/fsnotify/fsnotify v1.6.0 h1:n+5WquG0fcWoWp6xPWfHdbskMCQaFnG6PfBrh1Ky4HY=
 github.com/fsnotify/fsnotify v1.6.0/go.mod h1:sl3t1tCWJFWoRz9R8WJCbQihKKwmorjAbSClcnxKAGw=
+github.com/gballet/go-libpcsclite v0.0.0-20190607065134-2772fd86a8ff h1:tY80oXqGNY4FhTFhk+o9oFHGINQ/+vhlm8HFzi6znCI=
+github.com/gballet/go-libpcsclite v0.0.0-20190607065134-2772fd86a8ff/go.mod h1:x7DCsMOv1taUwEWCzT4cmDeAkigA5/QCwUodaVOe8Ww=
 github.com/getsentry/sentry-go v0.27.0 h1:Pv98CIbtB3LkMWmXi4Joa5OOcwbmnX88sF5qbK3r3Ps=
 github.com/getsentry/sentry-go v0.27.0/go.mod h1:lc76E2QywIyW8WuBnwl8Lc4bkmQH4+w1gwTf25trprY=
+github.com/go-ole/go-ole v1.2.5/go.mod h1:pprOEPIfldk/42T2oK7lQ4v4JSDwmV0As9GaiUsvbm0=
 github.com/go-ole/go-ole v1.3.0 h1:Dt6ye7+vXGIKZ7Xtk4s6/xVdGDQynvom7xCFEdWr6uE=
 github.com/go-ole/go-ole v1.3.0/go.mod h1:5LS6F96DhAwUc7C+1HLexzMXY1xGRSryjyPPKW6zv78=
 github.com/go-redis/redis/v8 v8.11.5 h1:AcZZR7igkdvfVmQTPnu9WE37LRrO/YrBH5zWyjDC0oI=
@@ -70,6 +81,8 @@ github.com/gofrs/flock v0.8.1 h1:+gYjHKf32LDeiEEFhQaotPbLuUXjY5ZqxKgXy7n59aw=
 github.com/gofrs/flock v0.8.1/go.mod h1:F1TvTiK9OcQqauNUHlbJvyl9Qa1QvF/gOUDKA14jxHU=
 github.com/gogo/protobuf v1.3.2 h1:Ov1cvc58UF3b5XjBnZv7+opcTcQFZebYjWzi34vdm4Q=
 github.com/gogo/protobuf v1.3.2/go.mod h1:P1XiOD3dCwIKUDQYPy72D8LYyHL2YPYrpS2s69NZV8Q=
+github.com/golang-jwt/jwt/v4 v4.5.0 h1:7cYmW1XlMY7h7ii7UhUyChSgS5wUJEnm9uZVTGqOWzg=
+github.com/golang-jwt/jwt/v4 v4.5.0/go.mod h1:m21LjoU+eqJr34lmDMbreY2eSTRJ1cv77w39/MY0Ch0=
 github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
 github.com/golang/protobuf v1.5.4/go.mod h1:lnTiLA8Wa4RWRcIUkrtSVa5nRhsEGBg48fD6rSs7xps=
 github.com/golang/snappy v0.0.5-0.20220116011046-fa5810519dcb h1:PBC98N2aIaM3XXiurYmW7fx4GZkL8feAMVq7nEjURHk=
@@ -79,8 +92,20 @@ github.com/gomodule/redigo v1.8.5/go.mod h1:P9dn9mFrCBvWhGE1wpxx6fgq7BAeLBk+UUUz
 github.com/google/subcommands v1.2.0/go.mod h1:ZjhPrFU+Olkh9WazFPsl27BQ4UPiG37m3yTrtFlrHVk=
 github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/gorilla/websocket v1.4.2 h1:+/TMaTYc4QFitKJxsQ7Yye35DkWvkdLcvGKqM+x0Ufc=
+github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
+github.com/hashicorp/go-bexpr v0.1.10 h1:9kuI5PFotCboP3dkDYFr/wi0gg0QVbSNz5oFRpxn4uE=
+github.com/hashicorp/go-bexpr v0.1.10/go.mod h1:oxlubA2vC/gFVfX1A6JGp7ls7uCDlfJn732ehYYg+g0=
+github.com/holiman/billy v0.0.0-20240216141850-2abb0c79d3c4 h1:X4egAf/gcS1zATw6wn4Ej8vjuVGxeHdan+bRb2ebyv4=
+github.com/holiman/billy v0.0.0-20240216141850-2abb0c79d3c4/go.mod h1:5GuXa7vkL8u9FkFuWdVvfR5ix8hRB7DbOAaYULamFpc=
+github.com/holiman/bloomfilter/v2 v2.0.3 h1:73e0e/V0tCydx14a0SCYS/EWCxgwLZ18CZcZKVu0fao=
+github.com/holiman/bloomfilter/v2 v2.0.3/go.mod h1:zpoh+gs7qcpqrHr3dB55AMiJwo0iURXE7ZOP9L9hSkA=
 github.com/holiman/uint256 v1.3.0 h1:4wdcm/tnd0xXdu7iS3ruNvxkWwrb4aeBQv19ayYn8F4=
 github.com/holiman/uint256 v1.3.0/go.mod h1:EOMSn4q6Nyt9P6efbI3bueV4e1b3dGlUCXeiRV4ng7E=
+github.com/huin/goupnp v1.3.0 h1:UvLUlWDNpoUdYzb2TCn+MuTWtcjXKSza2n6CBdQ0xXc=
+github.com/huin/goupnp v1.3.0/go.mod h1:gnGPsThkYa7bFi/KWmEysQRf48l2dvR5bxr2OFckNX8=
+github.com/jackpal/go-nat-pmp v1.0.2 h1:KzKSgb7qkJvOUTqYl9/Hg/me3pWgBmERKrTGD7BdWus=
+github.com/jackpal/go-nat-pmp v1.0.2/go.mod h1:QPH045xvCAeXUZOxsnwmrtiCoxIr9eob+4orBN1SBKc=
 github.com/jarcoal/httpmock v1.0.8 h1:8kI16SoO6LQKgPE7PvQuV+YuD/inwHd7fOOe2zMbo4k=
 github.com/jarcoal/httpmock v1.0.8/go.mod h1:ATjnClrvW/3tijVmpL/va5Z3aAyGvqU3gCT8nX0Txik=
 github.com/jmoiron/sqlx v1.3.4 h1:wv+0IJZfL5z0uZoUjlpKgHkgaFSYD+r9CfrXjEXsO7w=
@@ -98,6 +123,10 @@ github.com/leanovate/gopter v0.2.9/go.mod h1:U2L/78B+KVFIx2VmW6onHJQzXtFb+p5y3y2
 github.com/lib/pq v1.2.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
 github.com/lib/pq v1.10.7 h1:p7ZhMD+KsSRozJr34udlUrhboJwWAgCg34+/ZZNvZZw=
 github.com/lib/pq v1.10.7/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
+github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mattn/go-runewidth v0.0.13 h1:lTGmDsbAYt5DmK6OnoV7EuIF1wEIFAcxld6ypU4OSgU=
 github.com/mattn/go-runewidth v0.0.13/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
 github.com/mattn/go-sqlite3 v1.14.6 h1:dNPt6NO46WmLVt2DLNpwczCmdV5boIZ6g/tlDrlRUbg=
@@ -106,6 +135,10 @@ github.com/matttproud/golang_protobuf_extensions v1.0.2-0.20181231171920-c182aff
 github.com/matttproud/golang_protobuf_extensions v1.0.2-0.20181231171920-c182affec369/go.mod h1:BSXmuO+STAnVfrANrmjBb36TMTDstsz7MSK+HVaYKv4=
 github.com/metachris/flashbotsrpc v0.7.0 h1:DFpWWgaKE1hLARb5yNvKAiD5pb/VyGU4jrjhTH62ltQ=
 github.com/metachris/flashbotsrpc v0.7.0/go.mod h1:UrS249kKA1PK27sf12M6tUxo/M4ayfFrBk7IMFY1TNw=
+github.com/mitchellh/mapstructure v1.4.1 h1:CpVNEelQCZBooIPDn+AR3NpivK/TIKU8bDxdASFVQag=
+github.com/mitchellh/mapstructure v1.4.1/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
+github.com/mitchellh/pointerstructure v1.2.0 h1:O+i9nHnXS3l/9Wu7r4NrEdwA2VFTicjUEN1uBnDo34A=
+github.com/mitchellh/pointerstructure v1.2.0/go.mod h1:BRAsLI5zgXmw97Lf6s25bs8ohIXc3tViBH44KcwB2g4=
 github.com/mmcloughlin/addchain v0.4.0 h1:SobOdjm2xLj1KkXN5/n0xTIWyZA2+s99UCY1iPfkHRY=
 github.com/mmcloughlin/addchain v0.4.0/go.mod h1:A86O+tHqZLMNO4w6ZZ4FlVQEadcoqkyU72HC5wJ4RlU=
 github.com/mmcloughlin/profile v0.1.1/go.mod h1:IhHD7q1ooxgwTgjxQYkACGA77oFTDdFVejUS1/tS/qU=
@@ -133,8 +166,14 @@ github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
 github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/rogpeppe/go-internal v1.9.0 h1:73kH8U+JUqXU8lRuOHeVHaa/SZPifC7BkcraZVejAe8=
 github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
+github.com/rs/cors v1.7.0 h1:+88SsELBHx5r+hZ8TCkggzSstaWNbDvThkVK8H6f9ik=
+github.com/rs/cors v1.7.0/go.mod h1:gFx+x8UowdsKA9AchylcLynDq+nNFfI8FkUZdN/jGCU=
+github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/shirou/gopsutil v3.21.4-0.20210419000835-c7a38de76ee5+incompatible h1:Bn1aCHHRnjv4Bl16T8rcaFjYSrGrIZvpiGO6P3Q4GpU=
 github.com/shirou/gopsutil v3.21.4-0.20210419000835-c7a38de76ee5+incompatible/go.mod h1:5b4v6he4MtMOwMlS0TUMTu2PcXUg8+E1lC7eC3UO/RA=
+github.com/status-im/keycard-go v0.2.0 h1:QDLFswOQu1r5jsycloeQh3bVU8n/NatHHaZobtDnDzA=
+github.com/status-im/keycard-go v0.2.0/go.mod h1:wlp8ZLbsmrF6g6WjugPAx+IzoLrkdf9+mHxBEeo3Hbg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
@@ -153,6 +192,12 @@ github.com/tklauser/go-sysconf v0.3.12 h1:0QaGUFOdQaIVdPgfITYzaTegZvdCjmYO52cSFA
 github.com/tklauser/go-sysconf v0.3.12/go.mod h1:Ho14jnntGE1fpdOqQEEaiKRpvIavV0hSfmBq8nJbHYI=
 github.com/tklauser/numcpus v0.6.1 h1:ng9scYS7az0Bk4OZLvrNXNSAO2Pxr1XXRAPyjhIx+Fk=
 github.com/tklauser/numcpus v0.6.1/go.mod h1:1XfjsgE2zo8GVw7POkMbHENHzVg3GzmoZ9fESEdAacY=
+github.com/tyler-smith/go-bip39 v1.1.0 h1:5eUemwrMargf3BSLRRCalXT93Ns6pQJIjYQN2nyfOP8=
+github.com/tyler-smith/go-bip39 v1.1.0/go.mod h1:gUYDtqQw1JS3ZJ8UWVcGTGqqr6YIN3CWg+kkNaLt55U=
+github.com/urfave/cli/v2 v2.25.7 h1:VAzn5oq403l5pHjc4OhD54+XGO9cdKVL/7lDjF+iKUs=
+github.com/urfave/cli/v2 v2.25.7/go.mod h1:8qnjx1vcq5s2/wpsqoZFndg2CE5tNFyrTvS6SinrnYQ=
+github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 h1:bAn7/zixMGCfxrRTfdpNzjtPYqr8smhKouy9mxVdGPU=
+github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673/go.mod h1:N3UwUGtsrSj3ccvlPHLoLsHnpR27oXr4ZE984MbSER8=
 github.com/yuin/gopher-lua v0.0.0-20200816102855-ee81675732da h1:NimzV1aGyq29m5ukMK0AMWEhFaL/lrEOaephfuoiARg=
 github.com/yuin/gopher-lua v0.0.0-20200816102855-ee81675732da/go.mod h1:E1AXubJBdNmFERAOucpDIxNzeGfLzg0mYh+UfMWdChA=
 golang.org/x/crypto v0.22.0 h1:g1v0xeRhjcugydODzvb3mEM9SQ0HGp9s/nh3COQ/C30=
@@ -164,15 +209,23 @@ golang.org/x/net v0.24.0/go.mod h1:2Q7sJY5mzlzWjKtYUEXSlBWCdyaioyXzRB2RtU8KVE8=
 golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
 golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20190204203706-41f3e6584952/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190916202348-b4ddaad3f8a3/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.1.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.8.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.11.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.20.0 h1:Od9JTbYCk261bKm4M/mw7AklTlFYIa0bIp9BgSm1S8Y=
 golang.org/x/sys v0.20.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
 golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
+golang.org/x/time v0.5.0 h1:o7cqy6amK/52YcAKIPlM3a+Fpj35zvRj2TP+e1xFSfk=
+golang.org/x/time v0.5.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=
 google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
 google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
+gopkg.in/natefinch/lumberjack.v2 v2.2.1 h1:bBRl1b0OH9s/DuPhuXpNl+VtCaJXFZ5/uEFST95x9zc=
+gopkg.in/natefinch/lumberjack.v2 v2.2.1/go.mod h1:YD8tP3GAjkrDg1eZH7EGmyESg/lsYskCTPBJVb9jqSc=
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 h1:uRGJdciOHaEIrze2W8Q3AKkepLTh2hOroT7a+7czfdQ=
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWDmTeBkI65Dw0HsyUHuEVlX15mw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

server/configuration.go

@@ -22,4 +22,5 @@ type Configuration struct {
 	BuilderInfoSource   string
 	FetchInfoInterval   int
 	TTLCacheSeconds     int64
+	DefaultMempoolRPC   string
 }

server/request_handler.go

@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"time"
 
+	"github.com/ethereum/go-ethereum/ethclient"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/google/uuid"
 	"golang.org/x/exp/rand"
@@ -33,6 +34,7 @@ type RpcRequestHandler struct {
 	builderNames        []string
 	chainID             []byte
 	rpcCache            *application.RpcCache
+	defaultEthClient    *ethclient.Client
 }
 
 func NewRpcRequestHandler(
@@ -47,6 +49,7 @@ func NewRpcRequestHandler(
 	builderNames []string,
 	chainID []byte,
 	rpcCache *application.RpcCache,
+	defaultEthClient *ethclient.Client,
 ) *RpcRequestHandler {
 	return &RpcRequestHandler{
 		logger:              logger,
@@ -62,6 +65,7 @@ func NewRpcRequestHandler(
 		builderNames:        builderNames,
 		chainID:             chainID,
 		rpcCache:            rpcCache,
+		defaultEthClient:    defaultEthClient,
 	}
 }
 
@@ -146,7 +150,7 @@ func (r *RpcRequestHandler) processRequest(client RPCProxyClient, jsonReq *types
 		r.logger.Info("[processRequest] eth_sendRawTransaction request URL", "url", reqURL)
 	}
 	// Handle single request
-	rpcReq := NewRpcRequest(r.logger, client, jsonReq, r.relaySigningKey, r.relayUrl, origin, referer, isWhitehatBundleCollection, whitehatBundleId, entry, urlParams, r.chainID, r.rpcCache)
+	rpcReq := NewRpcRequest(r.logger, client, jsonReq, r.relaySigningKey, r.relayUrl, origin, referer, isWhitehatBundleCollection, whitehatBundleId, entry, urlParams, r.chainID, r.rpcCache, r.defaultEthClient)
 
 	if err := rpcReq.CheckFlashbotsSignature(r.req.Header.Get("X-Flashbots-Signature"), body); err != nil {
 		r.logger.Warn("[processRequest] CheckFlashbotsSignature", "error", err)

server/request_processor.go

@@ -4,6 +4,7 @@ Request represents an incoming client request
 package server
 
 import (
+	"context"
 	"crypto/ecdsa"
 	"encoding/json"
 	"errors"
@@ -13,6 +14,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/ethereum/go-ethereum/ethclient"
 	"github.com/flashbots/rpc-endpoint/adapters/flashbots"
 	"github.com/flashbots/rpc-endpoint/application"
 	"github.com/flashbots/rpc-endpoint/database"
@@ -28,6 +30,7 @@ import (
 type RpcRequest struct {
 	logger                     log.Logger
 	client                     RPCProxyClient
+	defaultEthClient           *ethclient.Client
 	jsonReq                    *types.JsonRpcRequest
 	jsonRes                    *types.JsonRpcResponse
 	rawTxHex                   string
@@ -58,6 +61,7 @@ func NewRpcRequest(
 	urlParams URLParameters,
 	chainID []byte,
 	rpcCache *application.RpcCache,
+	defaultEthClient *ethclient.Client,
 ) *RpcRequest {
 	return &RpcRequest{
 		logger:                     logger.With("method", jsonReq.Method),
@@ -73,6 +77,7 @@ func NewRpcRequest(
 		urlParams:                  urlParams,
 		chainID:                    chainID,
 		rpcCache:                   rpcCache,
+		defaultEthClient:           defaultEthClient,
 	}
 }
 
@@ -386,6 +391,26 @@ func (r *RpcRequest) handleCancelTx() (requestCompleted bool) {
 		return true
 	}
 
+	if r.urlParams.pref.Privacy.UseMempool {
+		r.logger.Info("[cancelTx] cancel-tx sending to mempool", "tx", initialTxHash)
+		ethCl := r.defaultEthClient
+		if r.urlParams.pref.Privacy.MempoolRPC != "" {
+			ethCl, err = ethclient.Dial(r.urlParams.pref.Privacy.MempoolRPC)
+			if err != nil {
+				r.logger.Error("[cancelTx] Dial failed", "error", err, "rpc", r.urlParams.pref.Privacy.MempoolRPC)
+				r.writeRpcError("invalid mempool rpc", types.JsonRpcInvalidParams)
+				return true
+			}
+		}
+
+		err = ethCl.SendTransaction(context.Background(), r.tx)
+		if err != nil {
+			r.logger.Error("[cancelTx] SendTransaction failed", "error", err)
+			r.writeRpcError("proxying cancellation to mempool failed", types.JsonRpcInternalError)
+			return true
+		}
+	}
+
 	cancelPrivTxArgs := flashbotsrpc.FlashbotsCancelPrivateTransactionRequest{TxHash: initialTxHash}
 
 	fbRpc := flashbotsrpc.New(r.relayUrl)