Fallback to max gas limit in estimategas (#4853)

Fallback to max gas limit

core/services/pipeline/runner.go

@@ -237,6 +237,7 @@ func (r *runner) run(
 			task.(*VRFTaskV2).keyStore = r.vrfKeyStore
 		case TaskTypeEstimateGasLimit:
 			task.(*EstimateGasLimitTask).GasEstimator = r.ethClient
+			task.(*EstimateGasLimitTask).EvmGasLimit = r.config.EvmGasLimitDefault()
 		case TaskTypeETHTx:
 			task.(*ETHTxTask).db = r.orm.DB()
 			task.(*ETHTxTask).config = r.config

core/services/pipeline/task.estimategas.go

@@ -4,6 +4,8 @@ import (
 	"context"
 	"strconv"
 
+	"github.com/smartcontractkit/chainlink/core/logger"
+
 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/pkg/errors"
@@ -22,14 +24,17 @@ type EstimateGasLimitTask struct {
 	Multiplier string `json:"multiplier"`
 	Data       string `json:"data"`
 
+	EvmGasLimit  uint64
 	GasEstimator GasEstimator
 }
 
 type GasEstimator interface {
 	EstimateGas(ctx context.Context, call ethereum.CallMsg) (uint64, error)
 }
 
-var _ Task = (*EstimateGasLimitTask)(nil)
+var (
+	_ Task = (*EstimateGasLimitTask)(nil)
+)
 
 func (t *EstimateGasLimitTask) Type() TaskType {
 	return TaskTypeEstimateGasLimit
@@ -57,7 +62,10 @@ func (t *EstimateGasLimitTask) Run(_ context.Context, vars Vars, inputs []Result
 		Data: data,
 	})
 	if err != nil {
-		return Result{Error: err}
+		// Fallback to the maximum conceivable gas limit
+		// if we're unable to call estimate gas for whatever reason.
+		logger.Warnw("EstimateGas: unable to estimate, fallback to configured limit", "err", err, "fallback", t.EvmGasLimit)
+		return Result{Value: t.EvmGasLimit}
 	}
 	gasLimitDecimal, err := decimal.NewFromString(strconv.FormatUint(gasLimit, 10))
 	if err != nil {
@@ -67,5 +75,9 @@ func (t *EstimateGasLimitTask) Run(_ context.Context, vars Vars, inputs []Result
 	if !gasLimitWithMultiplier.IsUint64() {
 		return Result{Error: errors.New("Invalid multiplier")}
 	}
-	return Result{Value: gasLimitWithMultiplier.Uint64()}
+	gasLimitFinal := gasLimitWithMultiplier.Uint64()
+	if gasLimitFinal > t.EvmGasLimit {
+		gasLimitFinal = t.EvmGasLimit
+	}
+	return Result{Value: gasLimitFinal}
 }

core/services/vrf/integration_v2_test.go

@@ -144,7 +144,7 @@ func TestIntegrationVRFV2(t *testing.T) {
 	defer cleanupDB()
 	key := cltest.MustGenerateRandomKey(t)
 	uni := newVRFCoordinatorV2Universe(t, key)
-	config.Overrides.EvmGasLimitDefault = null.IntFrom(500000)
+	config.Overrides.EvmGasLimitDefault = null.IntFrom(2000000)
 
 	app, cleanup := cltest.NewApplicationWithConfigAndKeyOnSimulatedBlockchain(t, config, uni.backend, key)
 	defer cleanup()
@@ -287,11 +287,11 @@ func TestIntegrationVRFV2(t *testing.T) {
 	t.Logf("subscription charged %s with gas prices of %s gwei and %s ETH per LINK\n", linkCharged, gasPrice.Div(gwei), weiPerUnitLink.Div(wei))
 	expected := decimal.RequireFromString(strconv.Itoa(int(fulfillReceipt.GasUsed))).Mul(gasPrice).Div(weiPerUnitLink)
 	t.Logf("expected sub charge gas use %v %v off by %v", fulfillReceipt.GasUsed, expected, expected.Sub(linkCharged))
-	// The expected sub charge should be within 100 gas of the actual gas usage.
+	// The expected sub charge should be within 200 gas of the actual gas usage.
 	// wei/link * link / wei/gas = wei / (wei/gas) = gas
 	gasDiff := linkCharged.Sub(expected).Mul(weiPerUnitLink).Div(gasPrice).Abs().IntPart()
 	t.Log("gasDiff", gasDiff)
-	assert.Less(t, gasDiff, int64(100))
+	assert.Less(t, gasDiff, int64(200))
 
 	// Oracle tries to withdraw move than it was paid should fail
 	_, err = uni.rootContract.OracleWithdraw(uni.nallory, uni.nallory.From, linkWeiCharged.Add(decimal.NewFromInt(1)).BigInt())

core/testdata/tomlspecs/vrf-v2-spec.toml

@@ -19,10 +19,10 @@ encode_tx    [type=ethabiencode
               abi="fulfillRandomWords(bytes proof)"
               data="{\\"proof\\": $(vrf.proof)}"]
 estimate_gas [type=estimategaslimit
-			  to="%s"
+			  to="0xABA5eDc1a551E55b1A570c0e1f1055e5BE11eca7"
               multiplier="1.1"
               data="$(encode_tx)"]
-submit_tx  [type=ethtx to="%s"
+submit_tx  [type=ethtx to="0xABA5eDc1a551E55b1A570c0e1f1055e5BE11eca7"
             data="$(encode_tx)"
             gasLimit="$(estimate_gas)"
             txMeta="{\\"requestTxHash\\": $(jobRun.logTxHash),\\"requestID\\": $(vrf.requestID),\\"jobID\\": $(jobSpec.databaseID)}"]