TxSel avoid L1CoordTx for L2Tx that have a L1UserTx in the frozen queue

For the L2Txs of TransferToEthAddr & TransferToBJJ for a not-yet
existing accounts, in the TxSelector check if L2Tx receiver account will
be created by a L1UserFrozenTxs (in the next batch, the current frozen
queue). In that case, the L2Tx will be discarded at the current batch,
even if there is an AccountCreationAuth for the account, as there is a
L1UserTx in the frozen queue that will create the receiver Account.  The
L2Tx is discarded to avoid the Coordinator creating a new
L1CoordinatorTx to create the receiver account, which will be also
created in the next batch from the L1UserFrozenTx, ending with the user
having 2 different accounts for the same TokenID.
The double account creation is supported by the Hermez zkRollup
specification, but it was decided to mitigate it at the TxSelector level
for the explained cases.

.github/workflows/release.yml

@@ -0,0 +1,29 @@
+name: goreleaser
+
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  goreleaser:
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      -
+        name: Set up Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.16
+      -
+        name: Run GoReleaser
+        uses: goreleaser/goreleaser-action@v2
+        with:
+          version: latest
+          args: release --rm-dist
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.gitignore

@@ -1 +1,2 @@
-bin/
+bin/
+dist/

.goreleaser.yml

@@ -0,0 +1,35 @@
+before:
+  hooks:
+    - go mod download
+    - make migration-pack
+
+builds:
+  - main: ./cli/node/main.go
+    binary: node
+    id: node
+    goos:
+      - linux
+      - darwin
+    goarch:
+      - amd64
+
+archives:
+  - replacements:
+      darwin: Darwin
+      linux: Linux
+      windows: Windows
+      386: i386
+      amd64: x86_64
+
+checksum:
+  name_template: 'checksums.txt'
+
+snapshot:
+  name_template: "{{ .Tag }}-next"
+
+changelog:
+  sort: asc
+  filters:
+    exclude:
+      - '^docs:'
+      - '^test:'

Makefile

@@ -3,8 +3,8 @@
 # Project variables.
 PACKAGE := github.com/hermeznetwork/hermez-node
 VERSION := $(shell git describe --tags --always)
-BUILD := $(shell git rev-parse --short HEAD)
-BUILD_DATE := $(shell date +%Y-%m-%dT%H:%M:%S%z)
+COMMIT := $(shell git rev-parse --short HEAD)
+DATE := $(shell date +%Y-%m-%dT%H:%M:%S%z)
 PROJECT_NAME := $(shell basename "$(PWD)")
 
 # Go related variables.
@@ -23,7 +23,7 @@ CONFIG ?= $(GOBASE)/cli/node/cfg.buidler.toml
 POSTGRES_PASS ?= yourpasswordhere
 
 # Use linker flags to provide version/build settings.
-LDFLAGS=-ldflags "-X=main.Version=$(VERSION) -X=main.Build=$(BUILD) -X=main.Date=$(BUILD_DATE)"
+LDFLAGS=-ldflags "-X main.version=$(VERSION) -X main.commit=$(COMMIT) -X main.date=$(DATE)"
 
 # PID file will keep the process id of the server.
 PID_PROOF_MOCK := /tmp/.$(PROJECT_NAME).proof.pid
@@ -94,11 +94,11 @@ install:
 	@echo "  >  Checking if there is any missing dependencies..."
 	$(GOENVVARS) go get $(GOCMD)/... $(get)
 
-## run: Run Hermez node.
-run:
+## run-node: Run Hermez node.
+run-node:
 	@bash -c "$(MAKE) clean build"
 	@echo "  >  Running $(PROJECT_NAME)"
-	@$(GOBIN)/$(GOBINARY) --mode $(MODE) --cfg $(CONFIG) run
+	@$(GOBIN)/$(GOBINARY) run --mode $(MODE) --cfg $(CONFIG)
 
 ## run-proof-mock: Run proof server mock API.
 run-proof-mock: stop-proof-mock

README.md

@@ -25,13 +25,13 @@ there are more information about the config file into [cli/node/README.md](cli/n
 After setting the config, you can build and run the Hermez Node as a synchronizer:
 
 ```shell
-$ make run
+$ make run-node
 ```
 
 Or build and run as a coordinator, and also passing the config file from other location:
 
 ```shell
-$ MODE=sync CONFIG=cli/node/cfg.buidler.toml make run
+$ MODE=sync CONFIG=cli/node/cfg.buidler.toml make run-node
 ```
 
 To check the useful make commands:

api/api.go

@@ -7,6 +7,7 @@ import (
 	"github.com/gin-gonic/gin"
 	"github.com/hermeznetwork/hermez-node/db/historydb"
 	"github.com/hermeznetwork/hermez-node/db/l2db"
+	"github.com/hermeznetwork/hermez-node/metric"
 	"github.com/hermeznetwork/tracerr"
 )
 
@@ -50,6 +51,12 @@ func NewAPI(
 		hermezAddress: consts.HermezAddress,
 	}
 
+	middleware, err := metric.PrometheusMiddleware()
+	if err != nil {
+		return nil, err
+	}
+	server.Use(middleware)
+
 	v1 := server.Group("/v1")
 
 	// Add coordinator endpoints

api/api_test.go

@@ -522,11 +522,16 @@ func TestMain(m *testing.M) {
 		WithdrawalDelay: uint64(3000),
 	}
 
-	stateAPIUpdater = stateapiupdater.NewUpdater(hdb, nodeConfig, &common.SCVariables{
+	stateAPIUpdater, err = stateapiupdater.NewUpdater(hdb, nodeConfig, &common.SCVariables{
 		Rollup:   rollupVars,
 		Auction:  auctionVars,
 		WDelayer: wdelayerVars,
-	}, constants)
+	}, constants, &stateapiupdater.RecommendedFeePolicy{
+		PolicyType: stateapiupdater.RecommendedFeePolicyTypeAvgLastHour,
+	})
+	if err != nil {
+		panic(err)
+	}
 
 	// Generate test data, as expected to be received/sended from/to the API
 	testCoords := genTestCoordinators(commonCoords)

api/handlers.go

@@ -8,6 +8,7 @@ import (
 	"github.com/gin-gonic/gin"
 	"github.com/hermeznetwork/hermez-node/db/historydb"
 	"github.com/hermeznetwork/hermez-node/log"
+	"github.com/hermeznetwork/hermez-node/metric"
 	"github.com/hermeznetwork/tracerr"
 	"github.com/lib/pq"
 	"github.com/russross/meddler"
@@ -46,7 +47,9 @@ var (
 
 func retSQLErr(err error, c *gin.Context) {
 	log.Warnw("HTTP API SQL request error", "err", err)
-	errMsg := tracerr.Unwrap(err).Error()
+	unwrapErr := tracerr.Unwrap(err)
+	metric.CollectError(unwrapErr)
+	errMsg := unwrapErr.Error()
 	retDupKey := func(errCode pq.ErrorCode) {
 		// https://www.postgresql.org/docs/current/errcodes-appendix.html
 		if errCode == "23505" {
@@ -80,6 +83,7 @@ func retSQLErr(err error, c *gin.Context) {
 
 func retBadReq(err error, c *gin.Context) {
 	log.Warnw("HTTP API Bad request error", "err", err)
+	metric.CollectError(err)
 	c.JSON(http.StatusBadRequest, errorMsg{
 		Message: err.Error(),
 	})

api/stateapiupdater/stateapiupdater.go

@@ -2,10 +2,12 @@ package stateapiupdater
 
 import (
 	"database/sql"
+	"fmt"
 	"sync"
 
 	"github.com/hermeznetwork/hermez-node/common"
 	"github.com/hermeznetwork/hermez-node/db/historydb"
+	"github.com/hermeznetwork/hermez-node/log"
 	"github.com/hermeznetwork/tracerr"
 )
 
@@ -17,11 +19,45 @@ type Updater struct {
 	vars   common.SCVariablesPtr
 	consts historydb.Constants
 	rw     sync.RWMutex
+	rfp    *RecommendedFeePolicy
+}
+
+// RecommendedFeePolicy describes how the recommended fee is calculated
+type RecommendedFeePolicy struct {
+	PolicyType  RecommendedFeePolicyType `validate:"required"`
+	StaticValue float64
+}
+
+// RecommendedFeePolicyType describes the different available recommended fee strategies
+type RecommendedFeePolicyType string
+
+const (
+	// RecommendedFeePolicyTypeStatic always give the same StaticValue as recommended fee
+	RecommendedFeePolicyTypeStatic RecommendedFeePolicyType = "Static"
+	// RecommendedFeePolicyTypeAvgLastHour set the recommended fee using the average fee of the last hour
+	RecommendedFeePolicyTypeAvgLastHour RecommendedFeePolicyType = "AvgLastHour"
+)
+
+func (rfp *RecommendedFeePolicy) valid() bool {
+	switch rfp.PolicyType {
+	case RecommendedFeePolicyTypeStatic:
+		if rfp.StaticValue == 0 {
+			log.Warn("RcommendedFee is set to 0 USD, and the policy is static")
+		}
+		return true
+	case RecommendedFeePolicyTypeAvgLastHour:
+		return true
+	default:
+		return false
+	}
 }
 
 // NewUpdater creates a new Updater
 func NewUpdater(hdb *historydb.HistoryDB, config *historydb.NodeConfig, vars *common.SCVariables,
-	consts *historydb.Constants) *Updater {
+	consts *historydb.Constants, rfp *RecommendedFeePolicy) (*Updater, error) {
+	if ok := rfp.valid(); !ok {
+		return nil, tracerr.Wrap(fmt.Errorf("Invalid recommended fee policy: %v", rfp.PolicyType))
+	}
 	u := Updater{
 		hdb:    hdb,
 		config: *config,
@@ -31,9 +67,10 @@ func NewUpdater(hdb *historydb.HistoryDB, config *historydb.NodeConfig, vars *co
 				ForgeDelay: config.ForgeDelay,
 			},
 		},
+		rfp: rfp,
 	}
 	u.SetSCVars(vars.AsPtr())
-	return &u
+	return &u, nil
 }
 
 // Store the State in the HistoryDB
@@ -65,13 +102,27 @@ func (u *Updater) SetSCVars(vars *common.SCVariablesPtr) {
 
 // UpdateRecommendedFee update Status.RecommendedFee information
 func (u *Updater) UpdateRecommendedFee() error {
-	recommendedFee, err := u.hdb.GetRecommendedFee(u.config.MinFeeUSD, u.config.MaxFeeUSD)
-	if err != nil {
-		return tracerr.Wrap(err)
+	switch u.rfp.PolicyType {
+	case RecommendedFeePolicyTypeStatic:
+		u.rw.Lock()
+		u.state.RecommendedFee = common.RecommendedFee{
+			ExistingAccount:        u.rfp.StaticValue,
+			CreatesAccount:         u.rfp.StaticValue,
+			CreatesAccountInternal: u.rfp.StaticValue,
+		}
+		u.rw.Unlock()
+	case RecommendedFeePolicyTypeAvgLastHour:
+		recommendedFee, err := u.hdb.GetRecommendedFee(u.config.MinFeeUSD, u.config.MaxFeeUSD)
+		if err != nil {
+			return tracerr.Wrap(err)
+		}
+		u.rw.Lock()
+		u.state.RecommendedFee = *recommendedFee
+		u.rw.Unlock()
+	default:
+		return tracerr.New("Invalid recommende fee policy")
 	}
-	u.rw.Lock()
-	u.state.RecommendedFee = *recommendedFee
-	u.rw.Unlock()
+
 	return nil
 }
 

cli/node/README.md

@@ -73,6 +73,9 @@ of the node configuration.  Please, check the `type APIServer` at
   monitor the size of the folder to avoid running out of space.
 - The node requires a PostgreSQL database.  The parameters of the server and
   database must be set in the `PostgreSQL` section.
+- The node requires a web3 RPC server to work.  The node has only been tested
+  with geth and may not work correctly with other ethereum nodes
+  implementations.
 
 ## Building
 

cli/node/cfg.buidler.toml

@@ -35,7 +35,7 @@ Symbol = "SUSHI"
 Addr = "0x6b3595068778dd592e39a122f4f5a5cf09c90fe2"
 
 [Debug]
-APIAddress = "localhost:12345"
+APIAddress = "0.0.0.0:12345"
 MeddlerLogs = true
 GinDebugMode = true
 
@@ -145,3 +145,11 @@ Coordinator = true
 BatchPath = "/tmp/iden3-test/hermez/batchesdebug"
 LightScrypt = true
 # RollupVerifierIndex = 0
+
+[RecommendedFeePolicy]
+# Strategy used to calculate the recommended fee that the API will expose.
+# Available options:
+# - Static: always return the same value (StaticValue) in USD
+# - AvgLastHour: calculate using the average fee of the forged transactions during the last hour
+PolicyType = "Static"
+StaticValue = 0.99

cli/node/main.go

@@ -35,18 +35,18 @@ const (
 )
 
 var (
-	// Version represents the program based on the git tag
-	Version = "v0.1.0"
-	// Build represents the program based on the git commit
-	Build = "dev"
-	// Date represents the date of application was built
-	Date = ""
+	// version represents the program based on the git tag
+	version = "v0.1.0"
+	// commit represents the program based on the git commit
+	commit = "dev"
+	// date represents the date of application was built
+	date = ""
 )
 
 func cmdVersion(c *cli.Context) error {
-	fmt.Printf("Version = \"%v\"\n", Version)
-	fmt.Printf("Build = \"%v\"\n", Build)
-	fmt.Printf("Date = \"%v\"\n", Date)
+	fmt.Printf("Version = \"%v\"\n", version)
+	fmt.Printf("Build = \"%v\"\n", commit)
+	fmt.Printf("Date = \"%v\"\n", date)
 	return nil
 }
 
@@ -421,7 +421,7 @@ func getConfigAPIServer(c *cli.Context) (*ConfigAPIServer, error) {
 func main() {
 	app := cli.NewApp()
 	app.Name = "hermez-node"
-	app.Version = Version
+	app.Version = version
 	flags := []cli.Flag{
 		&cli.StringFlag{
 			Name:     flagMode,

common/l1tx.go

@@ -22,7 +22,7 @@ type L1Tx struct {
 	// 	- L1UserTx: 0
 	// 	- L1CoordinatorTx: 1
 	TxID TxID `meddler:"id"`
-	// ToForgeL1TxsNum indicates in which the tx was forged / will be forged
+	// ToForgeL1TxsNum indicates in which L1UserTx queue the tx was forged / will be forged
 	ToForgeL1TxsNum *int64 `meddler:"to_forge_l1_txs_num"`
 	Position        int    `meddler:"position"`
 	// UserOrigin is set to true if the tx was originated by a user, false if it was

config/config.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/BurntSushi/toml"
 	ethCommon "github.com/ethereum/go-ethereum/common"
+	"github.com/hermeznetwork/hermez-node/api/stateapiupdater"
 	"github.com/hermeznetwork/hermez-node/common"
 	"github.com/hermeznetwork/hermez-node/priceupdater"
 	"github.com/hermeznetwork/tracerr"
@@ -299,7 +300,8 @@ type Node struct {
 	} `validate:"required"`
 	PostgreSQL PostgreSQL `validate:"required"`
 	Web3       struct {
-		// URL is the URL of the web3 ethereum-node RPC server
+		// URL is the URL of the web3 ethereum-node RPC server.  Only
+		// geth is officially supported.
 		URL string `validate:"required"`
 	} `validate:"required"`
 	Synchronizer struct {
@@ -346,8 +348,9 @@ type Node struct {
 		// can wait to stablish a SQL connection
 		SQLConnectionTimeout Duration
 	} `validate:"required"`
-	Debug       NodeDebug   `validate:"required"`
-	Coordinator Coordinator `validate:"-"`
+	RecommendedFeePolicy stateapiupdater.RecommendedFeePolicy `validate:"required"`
+	Debug                NodeDebug                            `validate:"required"`
+	Coordinator          Coordinator                          `validate:"-"`
 }
 
 // APIServer is the api server configuration parameters

coordinator/batch.go

@@ -80,6 +80,7 @@ type BatchInfo struct {
 	PipelineNum           int
 	BatchNum              common.BatchNum
 	ServerProof           prover.Client
+	ProofStart            time.Time
 	ZKInputs              *common.ZKInputs
 	Proof                 *prover.Proof
 	PublicInputs          []*big.Int

coordinator/coordinator.go

@@ -1,3 +1,43 @@
+/*
+Package coordinator handles all the logic related to forging batches as a
+coordinator in the hermez network.
+
+The forging of batches is done with a pipeline in order to allow multiple
+batches being forged in parallel.  The maximum number of batches that can be
+forged in parallel is determined by the number of available proof servers.
+
+The Coordinator begins with the pipeline stopped.  The main Coordinator
+goroutine keeps listening for synchronizer events sent by the node package,
+which allow the coordinator to determine if the configured forger address is
+allowed to forge at the current block or not.  When the forger address becomes
+allowed to forge, the pipeline is started, and when it terminates being allowed
+to forge, the pipeline is stopped.
+
+The Pipeline consists of two goroutines.  The first one is in charge of
+preparing a batch internally, which involves making a selection of transactions
+and calculating the ZKInputs for the batch proof, and sending these ZKInputs to
+an idle proof server.  This goroutine will keep preparing batches while there
+are idle proof servers, if the forging policy determines that a batch should be
+forged in the current state.  The second goroutine is in charge of waiting for
+the proof server to finish computing the proof, retreiving it, prepare the
+arguments for the `forgeBatch` Rollup transaction, and sending the result to
+the TxManager.  All the batch information moves between functions and
+goroutines via the BatchInfo struct.
+
+Finally, the TxManager contains a single goroutine that makes forgeBatch
+ethereum transactions for the batches sent by the Pipeline, and keeps them in a
+list to check them periodically.  In the periodic checks, the ethereum
+transaction is checked for successfulness, and it's only forgotten after a
+number of confirmation blocks have passed after being successfully mined.  At
+any point if a transaction failure is detected, the TxManager can signal the
+Coordinator to reset the Pipeline in order to reforge the failed batches.
+
+The Coordinator goroutine acts as a manager.  The synchronizer events (which
+notify about new blocks and associated new state) that it receives are
+broadcasted to the Pipeline and the TxManager.  This allows the Coordinator,
+Pipeline and TxManager to have a copy of the current hermez network state
+required to perform their duties.
+*/
 package coordinator
 
 import (

coordinator/pipeline.go

@@ -5,6 +5,7 @@ import (
 	"database/sql"
 	"fmt"
 	"math/big"
+	"strconv"
 	"sync"
 	"time"
 
@@ -14,6 +15,7 @@ import (
 	"github.com/hermeznetwork/hermez-node/db/l2db"
 	"github.com/hermeznetwork/hermez-node/eth"
 	"github.com/hermeznetwork/hermez-node/log"
+	"github.com/hermeznetwork/hermez-node/metric"
 	"github.com/hermeznetwork/hermez-node/prover"
 	"github.com/hermeznetwork/hermez-node/synchronizer"
 	"github.com/hermeznetwork/hermez-node/txselector"
@@ -246,6 +248,7 @@ func (p *Pipeline) handleForgeBatch(ctx context.Context,
 
 	// 3. Send the ZKInputs to the proof server
 	batchInfo.ServerProof = serverProof
+	batchInfo.ProofStart = time.Now()
 	if err := p.sendServerProof(ctx, batchInfo); ctx.Err() != nil {
 		return nil, ctx.Err()
 	} else if err != nil {
@@ -520,15 +523,30 @@ func (p *Pipeline) forgeBatch(batchNum common.BatchNum) (batchInfo *BatchInfo,
 		if err != nil {
 			return nil, nil, tracerr.Wrap(err)
 		}
+		// l1UserFutureTxs are the l1UserTxs that are not being forged
+		// in the next batch, but that are also in the queue for the
+		// future batches
+		l1UserFutureTxs, err := p.historyDB.GetUnforgedL1UserFutureTxs(p.state.lastForgeL1TxsNum + 1)
+		if err != nil {
+			return nil, nil, tracerr.Wrap(err)
+		}
+
 		coordIdxs, auths, l1UserTxs, l1CoordTxs, poolL2Txs, discardedL2Txs, err =
-			p.txSelector.GetL1L2TxSelection(p.cfg.TxProcessorConfig, _l1UserTxs)
+			p.txSelector.GetL1L2TxSelection(p.cfg.TxProcessorConfig, _l1UserTxs, l1UserFutureTxs)
 		if err != nil {
 			return nil, nil, tracerr.Wrap(err)
 		}
 	} else {
+		// get l1UserFutureTxs which are all the l1 pending in all the
+		// queues
+		l1UserFutureTxs, err := p.historyDB.GetUnforgedL1UserFutureTxs(p.state.lastForgeL1TxsNum) //nolint:gomnd
+		if err != nil {
+			return nil, nil, tracerr.Wrap(err)
+		}
+
 		// 2b: only L2 txs
 		coordIdxs, auths, l1CoordTxs, poolL2Txs, discardedL2Txs, err =
-			p.txSelector.GetL2TxSelection(p.cfg.TxProcessorConfig)
+			p.txSelector.GetL2TxSelection(p.cfg.TxProcessorConfig, l1UserFutureTxs)
 		if err != nil {
 			return nil, nil, tracerr.Wrap(err)
 		}
@@ -602,6 +620,9 @@ func (p *Pipeline) forgeBatch(batchNum common.BatchNum) (batchInfo *BatchInfo,
 
 // waitServerProof gets the generated zkProof & sends it to the SmartContract
 func (p *Pipeline) waitServerProof(ctx context.Context, batchInfo *BatchInfo) error {
+	defer metric.MeasureDuration(metric.WaitServerProof, batchInfo.ProofStart,
+		batchInfo.BatchNum.BigInt().String(), strconv.Itoa(batchInfo.PipelineNum))
+
 	proof, pubInputs, err := batchInfo.ServerProof.GetProof(ctx) // blocking call,
 	// until not resolved don't continue. Returns when the proof server has calculated the proof
 	if err != nil {

db/historydb/historydb.go

@@ -751,6 +751,24 @@ func (hdb *HistoryDB) GetUnforgedL1UserTxs(toForgeL1TxsNum int64) ([]common.L1Tx
 	return db.SlicePtrsToSlice(txs).([]common.L1Tx), tracerr.Wrap(err)
 }
 
+// GetUnforgedL1UserFutureTxs gets L1 User Txs to be forged after the L1Batch
+// with toForgeL1TxsNum (in one of the future batches, not in the next one).
+func (hdb *HistoryDB) GetUnforgedL1UserFutureTxs(toForgeL1TxsNum int64) ([]common.L1Tx, error) {
+	var txs []*common.L1Tx
+	err := meddler.QueryAll(
+		hdb.dbRead, &txs, // only L1 user txs can have batch_num set to null
+		`SELECT tx.id, tx.to_forge_l1_txs_num, tx.position, tx.user_origin,
+		tx.from_idx, tx.from_eth_addr, tx.from_bjj, tx.to_idx, tx.token_id,
+		tx.amount, NULL AS effective_amount,
+		tx.deposit_amount, NULL AS effective_deposit_amount,
+		tx.eth_block_num, tx.type, tx.batch_num
+		FROM tx WHERE batch_num IS NULL AND to_forge_l1_txs_num > $1
+		ORDER BY position;`,
+		toForgeL1TxsNum,
+	)
+	return db.SlicePtrsToSlice(txs).([]common.L1Tx), tracerr.Wrap(err)
+}
+
 // GetUnforgedL1UserTxsCount returns the count of unforged L1Txs (either in
 // open or frozen queues that are not yet forged)
 func (hdb *HistoryDB) GetUnforgedL1UserTxsCount() (int, error) {

db/historydb/historydb_test.go

@@ -699,34 +699,55 @@ func TestGetUnforgedL1UserTxs(t *testing.T) {
 		CreateAccountDeposit(1) B: 5
 		CreateAccountDeposit(1) C: 5
 		CreateAccountDeposit(1) D: 5
-
 		> block
+
+		> batchL1
+		> block
+
+		CreateAccountDeposit(1) E: 5
+		CreateAccountDeposit(1) F: 5
+		> block
+
 	`
 	tc := til.NewContext(uint16(0), 128)
 	blocks, err := tc.GenerateBlocks(set)
 	require.NoError(t, err)
 	// Sanity check
-	require.Equal(t, 1, len(blocks))
+	require.Equal(t, 3, len(blocks))
 	require.Equal(t, 5, len(blocks[0].Rollup.L1UserTxs))
 
-	toForgeL1TxsNum := int64(1)
-
 	for i := range blocks {
 		err = historyDB.AddBlockSCData(&blocks[i])
 		require.NoError(t, err)
 	}
 
-	l1UserTxs, err := historyDB.GetUnforgedL1UserTxs(toForgeL1TxsNum)
+	l1UserTxs, err := historyDB.GetUnforgedL1UserFutureTxs(0)
+	require.NoError(t, err)
+	assert.Equal(t, 7, len(l1UserTxs))
+
+	l1UserTxs, err = historyDB.GetUnforgedL1UserTxs(1)
 	require.NoError(t, err)
 	assert.Equal(t, 5, len(l1UserTxs))
 	assert.Equal(t, blocks[0].Rollup.L1UserTxs, l1UserTxs)
 
+	l1UserTxs, err = historyDB.GetUnforgedL1UserFutureTxs(1)
+	require.NoError(t, err)
+	assert.Equal(t, 2, len(l1UserTxs))
+
 	count, err := historyDB.GetUnforgedL1UserTxsCount()
 	require.NoError(t, err)
-	assert.Equal(t, 5, count)
+	assert.Equal(t, 7, count)
+
+	l1UserTxs, err = historyDB.GetUnforgedL1UserTxs(2)
+	require.NoError(t, err)
+	assert.Equal(t, 2, len(l1UserTxs))
+
+	l1UserTxs, err = historyDB.GetUnforgedL1UserFutureTxs(2)
+	require.NoError(t, err)
+	assert.Equal(t, 0, len(l1UserTxs))
 
 	// No l1UserTxs for this toForgeL1TxsNum
-	l1UserTxs, err = historyDB.GetUnforgedL1UserTxs(2)
+	l1UserTxs, err = historyDB.GetUnforgedL1UserTxs(3)
 	require.NoError(t, err)
 	assert.Equal(t, 0, len(l1UserTxs))
 }

eth/ethereum.go

@@ -245,15 +245,15 @@ func (c *EthereumClient) EthBlockByNumber(ctx context.Context, number int64) (*c
 	if number == -1 {
 		blockNum = nil
 	}
-	block, err := c.client.BlockByNumber(ctx, blockNum)
+	header, err := c.client.HeaderByNumber(ctx, blockNum)
 	if err != nil {
 		return nil, tracerr.Wrap(err)
 	}
 	b := &common.Block{
-		Num:        block.Number().Int64(),
-		Timestamp:  time.Unix(int64(block.Time()), 0),
-		ParentHash: block.ParentHash(),
-		Hash:       block.Hash(),
+		Num:        header.Number.Int64(),
+		Timestamp:  time.Unix(int64(header.Time), 0),
+		ParentHash: header.ParentHash,
+		Hash:       header.Hash(),
 	}
 	return b, nil
 }

metric/metric.go

@@ -0,0 +1,192 @@
+package metric
+
+import (
+	"time"
+
+	"github.com/hermeznetwork/hermez-node/log"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type (
+	// Metric represents the metric type
+	Metric string
+)
+
+const (
+	namespaceError      = "error"
+	namespaceSync       = "synchronizer"
+	namespaceTxSelector = "txselector"
+	namespaceAPI        = "api"
+)
+
+var (
+	// Errors errors count metric.
+	Errors = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: namespaceError,
+			Name:      "errors",
+			Help:      "",
+		}, []string{"error"})
+
+	// WaitServerProof duration time to get the calculated
+	// proof from the server.
+	WaitServerProof = prometheus.NewHistogramVec(
+		prometheus.HistogramOpts{
+			Namespace: namespaceSync,
+			Name:      "wait_server_proof",
+			Help:      "",
+		}, []string{"batch_number", "pipeline_number"})
+
+	// Reorgs block reorg count
+	Reorgs = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Namespace: namespaceSync,
+			Name:      "reorgs",
+			Help:      "",
+		})
+
+	// LastBlockNum last block synced
+	LastBlockNum = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceSync,
+			Name:      "synced_last_block_num",
+			Help:      "",
+		})
+
+	// EthLastBlockNum last eth block synced
+	EthLastBlockNum = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceSync,
+			Name:      "eth_last_block_num",
+			Help:      "",
+		})
+
+	// LastBatchNum last batch synced
+	LastBatchNum = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceSync,
+			Name:      "synced_last_batch_num",
+			Help:      "",
+		})
+
+	// EthLastBatchNum last eth batch synced
+	EthLastBatchNum = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceSync,
+			Name:      "eth_last_batch_num",
+			Help:      "",
+		})
+
+	// GetL2TxSelection L2 tx selection count
+	GetL2TxSelection = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "get_l2_txselection_total",
+			Help:      "",
+		})
+
+	// GetL1L2TxSelection L1L2 tx selection count
+	GetL1L2TxSelection = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "get_l1_l2_txselection_total",
+			Help:      "",
+		})
+
+	// SelectedL1CoordinatorTxs selected L1 coordinator tx count
+	SelectedL1CoordinatorTxs = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "selected_l1_coordinator_txs",
+			Help:      "",
+		})
+
+	// SelectedL1UserTxs selected L1 user tx count
+	SelectedL1UserTxs = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "selected_l1_user_txs",
+			Help:      "",
+		})
+
+	// SelectedL2Txs selected L2 tx count
+	SelectedL2Txs = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "selected_l2_txs",
+			Help:      "",
+		})
+
+	// DiscardedL2Txs discarded L2 tx count
+	DiscardedL2Txs = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "discarded_l2_txs",
+			Help:      "",
+		})
+)
+
+func init() {
+	if err := registerCollectors(); err != nil {
+		log.Error(err)
+	}
+}
+func registerCollectors() error {
+	if err := registerCollector(Errors); err != nil {
+		return err
+	}
+	if err := registerCollector(WaitServerProof); err != nil {
+		return err
+	}
+	if err := registerCollector(Reorgs); err != nil {
+		return err
+	}
+	if err := registerCollector(LastBlockNum); err != nil {
+		return err
+	}
+	if err := registerCollector(LastBatchNum); err != nil {
+		return err
+	}
+	if err := registerCollector(EthLastBlockNum); err != nil {
+		return err
+	}
+	if err := registerCollector(EthLastBatchNum); err != nil {
+		return err
+	}
+	if err := registerCollector(GetL2TxSelection); err != nil {
+		return err
+	}
+	if err := registerCollector(GetL1L2TxSelection); err != nil {
+		return err
+	}
+	if err := registerCollector(SelectedL1CoordinatorTxs); err != nil {
+		return err
+	}
+	if err := registerCollector(SelectedL1UserTxs); err != nil {
+		return err
+	}
+	return registerCollector(DiscardedL2Txs)
+}
+
+func registerCollector(collector prometheus.Collector) error {
+	err := prometheus.Register(collector)
+	if err != nil {
+		if _, ok := err.(prometheus.AlreadyRegisteredError); !ok {
+			return err
+		}
+	}
+	return nil
+}
+
+// MeasureDuration measure the method execution duration
+// and save it into a histogram metric
+func MeasureDuration(histogram *prometheus.HistogramVec, start time.Time, lvs ...string) {
+	duration := time.Since(start)
+	histogram.WithLabelValues(lvs...).Observe(float64(duration.Milliseconds()))
+}
+
+// CollectError collect the error message and increment
+// the error count
+func CollectError(err error) {
+	Errors.With(map[string]string{"error": err.Error()}).Inc()
+}

metric/request.go

@@ -0,0 +1,78 @@
+package metric
+
+import (
+	"strconv"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const (
+	favicon = "/favicon.ico"
+)
+
+// Prometheus contains the metrics gathered by the instance and its path
+type Prometheus struct {
+	reqCnt *prometheus.CounterVec
+	reqDur *prometheus.HistogramVec
+}
+
+// NewPrometheus generates a new set of metrics with a certain subsystem name
+func NewPrometheus() (*Prometheus, error) {
+	reqCnt := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: namespaceAPI,
+			Name:      "requests_total",
+			Help:      "How many HTTP requests processed, partitioned by status code and HTTP method",
+		},
+		[]string{"code", "method", "path"},
+	)
+	if err := registerCollector(reqCnt); err != nil {
+		return nil, err
+	}
+	reqDur := prometheus.NewHistogramVec(
+		prometheus.HistogramOpts{
+			Namespace: namespaceAPI,
+			Name:      "request_duration_seconds",
+			Help:      "The HTTP request latencies in seconds",
+		},
+		[]string{"code", "method", "path"},
+	)
+	if err := registerCollector(reqDur); err != nil {
+		return nil, err
+	}
+	return &Prometheus{
+		reqCnt: reqCnt,
+		reqDur: reqDur,
+	}, nil
+}
+
+// PrometheusMiddleware creates the prometheus collector and
+// defines status handler function for the middleware
+func PrometheusMiddleware() (gin.HandlerFunc, error) {
+	p, err := NewPrometheus()
+	if err != nil {
+		return nil, err
+	}
+	return p.Middleware(), nil
+}
+
+// Middleware defines status handler function for middleware
+func (p *Prometheus) Middleware() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		if c.Request.URL.Path == favicon {
+			c.Next()
+			return
+		}
+		start := time.Now()
+		c.Next()
+
+		status := strconv.Itoa(c.Writer.Status())
+		elapsed := float64(time.Since(start)) / float64(time.Second)
+		fullPath := c.FullPath()
+
+		p.reqDur.WithLabelValues(status, c.Request.Method, fullPath).Observe(elapsed)
+		p.reqCnt.WithLabelValues(status, c.Request.Method, fullPath).Inc()
+	}
+}

node/node.go

@@ -1,3 +1,18 @@
+/*
+Package node does the initialization of all the required objects to either run
+as a synchronizer or as a coordinator.
+
+The Node contains several goroutines that run in the background or that
+periodically perform tasks.  One of this goroutines periodically calls the
+`Synchronizer.Sync` function, allowing the synchronization of one block at a
+time.  After every call to `Synchronizer.Sync`, the Node sends a message to the
+Coordinator to notify it about the new synced block (and associated state) or
+reorg (and resetted state) in case one happens.
+
+Other goroutines perform tasks such as: updating the token prices, update
+metrics stored in the historyDB, update recommended fee stored in the
+historyDB, run the http API server, run the debug http API server, etc.
+*/
 package node
 
 import (
@@ -273,7 +288,16 @@ func NewNode(mode Mode, cfg *config.Node) (*Node, error) {
 		return nil, tracerr.Wrap(err)
 	}
 
-	stateAPIUpdater := stateapiupdater.NewUpdater(historyDB, &hdbNodeCfg, initSCVars, &hdbConsts)
+	stateAPIUpdater, err := stateapiupdater.NewUpdater(
+		historyDB,
+		&hdbNodeCfg,
+		initSCVars,
+		&hdbConsts,
+		&cfg.RecommendedFeePolicy,
+	)
+	if err != nil {
+		return nil, tracerr.Wrap(err)
+	}
 
 	var coord *coordinator.Coordinator
 	if mode == ModeCoordinator {

synchronizer/metrics.go

@@ -1,44 +0,0 @@
-package synchronizer
-
-import "github.com/prometheus/client_golang/prometheus"
-
-var (
-	metricReorgsCount = prometheus.NewCounter(
-		prometheus.CounterOpts{
-			Name: "sync_reorgs",
-			Help: "",
-		},
-	)
-	metricSyncedLastBlockNum = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "sync_synced_last_block_num",
-			Help: "",
-		},
-	)
-	metricEthLastBlockNum = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "sync_eth_last_block_num",
-			Help: "",
-		},
-	)
-	metricSyncedLastBatchNum = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "sync_synced_last_batch_num",
-			Help: "",
-		},
-	)
-	metricEthLastBatchNum = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "sync_eth_last_batch_num",
-			Help: "",
-		},
-	)
-)
-
-func init() {
-	prometheus.MustRegister(metricReorgsCount)
-	prometheus.MustRegister(metricSyncedLastBlockNum)
-	prometheus.MustRegister(metricEthLastBlockNum)
-	prometheus.MustRegister(metricSyncedLastBatchNum)
-	prometheus.MustRegister(metricEthLastBatchNum)
-}

synchronizer/synchronizer.go

@@ -1,3 +1,35 @@
+/*
+Package synchronizer synchronizes the hermez network state by querying events
+emitted by the three smart contracts: `Hermez.sol` (referred as Rollup here),
+`HermezAuctionProtocol.sol` (referred as Auction here) and
+`WithdrawalDelayer.sol` (referred as WDelayer here).
+
+The main entry point for synchronization is the `Sync` function, which at most
+will synchronize one ethereum block, and all the hermez events that happened in
+that block.  During a `Sync` call, a reorg can be detected; in such case, uncle
+blocks will be discarded, and only in a future `Sync` call correct blocks will
+be synced.
+
+The synchronization of the events in each smart contracts are done
+in the methods `rollupSync`, `auctionSync` and `wdelayerSync`, which in turn
+use the interface code to read each smart contract state and events found in
+"github.com/hermeznetwork/hermez-node/eth".  After these three methods are
+called, an object of type `common.BlockData` is built containing all the
+updates and events that happened in that block, and it is inserted in the
+HistoryDB in a single SQL transaction.
+
+`rollupSync` is the method that synchronizes batches sent via the `forgeBatch`
+transaction in `Hermez.sol`.  In `rollupSync`, for every batch,  the accounts
+state is updated in the StateDB by processing all transactions that have been
+forged in that batch.
+
+The consistency of the stored data is guaranteed by the HistoryDB: All the
+block information is inserted in a single SQL transaction at the end of the
+`Sync` method, once the StateDB has been updated.  And every time the
+Synchronizer starts, it continues from the last block in the HistoryDB.  The
+StateDB stores updates organized by checkpoints for every batch, and each batch
+is only accessed if it appears in the HistoryDB.
+*/
 package synchronizer
 
 import (
@@ -15,6 +47,7 @@ import (
 	"github.com/hermeznetwork/hermez-node/db/statedb"
 	"github.com/hermeznetwork/hermez-node/eth"
 	"github.com/hermeznetwork/hermez-node/log"
+	"github.com/hermeznetwork/hermez-node/metric"
 	"github.com/hermeznetwork/hermez-node/txprocessor"
 	"github.com/hermeznetwork/tracerr"
 )
@@ -23,12 +56,6 @@ const (
 	// errStrUnknownBlock is the string returned by geth when querying an
 	// unknown block
 	errStrUnknownBlock = "unknown block"
-	// updateEthBlockNumThreshold is a threshold of number of ethereum blocks left to synchronize, such that
-	// if we have more blocks to sync than the defined value we can aggressively skip calling UpdateEth
-	updateEthBlockNumThreshold = 100
-	// While having more blocks to sync than updateEthBlockNumThreshold, UpdateEth will be called once in a
-	// defined number of blocks
-	updateEthFrequencyDivider = 100
 )
 
 var (
@@ -534,11 +561,8 @@ func (s *Synchronizer) Sync(ctx context.Context,
 	log.Debugf("ethBlock: num: %v, parent: %v, hash: %v",
 		ethBlock.Num, ethBlock.ParentHash.String(), ethBlock.Hash.String())
 
-	if nextBlockNum+updateEthBlockNumThreshold >= s.stats.Eth.LastBlock.Num ||
-		nextBlockNum%updateEthFrequencyDivider == 0 {
-		if err := s.stats.UpdateEth(s.ethClient); err != nil {
-			return nil, nil, tracerr.Wrap(err)
-		}
+	if err := s.stats.UpdateEth(s.ethClient); err != nil {
+		return nil, nil, tracerr.Wrap(err)
 	}
 
 	log.Debugw("Syncing...",
@@ -558,6 +582,7 @@ func (s *Synchronizer) Sync(ctx context.Context,
 				return nil, nil, tracerr.Wrap(err)
 			}
 			discarded := lastSavedBlock.Num - lastDBBlockNum
+			metric.Reorgs.Inc()
 			return nil, &discarded, nil
 		}
 	}
@@ -650,16 +675,16 @@ func (s *Synchronizer) Sync(ctx context.Context,
 	}
 
 	for _, batchData := range rollupData.Batches {
-		metricSyncedLastBatchNum.Set(float64(batchData.Batch.BatchNum))
-		metricEthLastBatchNum.Set(float64(s.stats.Eth.LastBatchNum))
+		metric.LastBatchNum.Set(float64(batchData.Batch.BatchNum))
+		metric.EthLastBatchNum.Set(float64(s.stats.Eth.LastBatchNum))
 		log.Debugw("Synced batch",
 			"syncLastBatch", batchData.Batch.BatchNum,
 			"syncBatchesPerc", s.stats.batchesPerc(batchData.Batch.BatchNum),
 			"ethLastBatch", s.stats.Eth.LastBatchNum,
 		)
 	}
-	metricSyncedLastBlockNum.Set(float64(s.stats.Sync.LastBlock.Num))
-	metricEthLastBlockNum.Set(float64(s.stats.Eth.LastBlock.Num))
+	metric.LastBlockNum.Set(float64(s.stats.Sync.LastBlock.Num))
+	metric.EthLastBlockNum.Set(float64(s.stats.Eth.LastBlock.Num))
 	log.Debugw("Synced block",
 		"syncLastBlockNum", s.stats.Sync.LastBlock.Num,
 		"syncBlocksPerc", s.stats.blocksPerc(),

test/zkproof/flows_test.go

@@ -156,7 +156,7 @@ func TestTxSelectorBatchBuilderZKInputsMinimumFlow0(t *testing.T) {
 		}
 		// TxSelector select the transactions for the next Batch
 		coordIdxs, _, oL1UserTxs, oL1CoordTxs, oL2Txs, _, err :=
-			txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs)
+			txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs, nil)
 		require.NoError(t, err)
 		// BatchBuilder build Batch
 		zki, err := bb.BuildBatch(coordIdxs, configBatch, oL1UserTxs, oL1CoordTxs, oL2Txs)
@@ -180,7 +180,7 @@ func TestTxSelectorBatchBuilderZKInputsMinimumFlow0(t *testing.T) {
 	l1UserTxs := til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[6].Batch.ForgeL1TxsNum])
 	// TxSelector select the transactions for the next Batch
 	coordIdxs, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
-		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs)
+		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs, nil)
 	require.NoError(t, err)
 	// BatchBuilder build Batch
 	zki, err := bb.BuildBatch(coordIdxs, configBatch, oL1UserTxs, oL1CoordTxs, oL2Txs)
@@ -209,7 +209,7 @@ func TestTxSelectorBatchBuilderZKInputsMinimumFlow0(t *testing.T) {
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[7].Batch.ForgeL1TxsNum])
 	// TxSelector select the transactions for the next Batch
 	coordIdxs, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs)
+		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs, nil)
 	require.NoError(t, err)
 	// BatchBuilder build Batch
 	zki, err = bb.BuildBatch(coordIdxs, configBatch, oL1UserTxs, oL1CoordTxs, oL2Txs)
@@ -236,7 +236,7 @@ func TestTxSelectorBatchBuilderZKInputsMinimumFlow0(t *testing.T) {
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[1].Rollup.Batches[0].Batch.ForgeL1TxsNum])
 	// TxSelector select the transactions for the next Batch
 	coordIdxs, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs)
+		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs, nil)
 	require.NoError(t, err)
 	// BatchBuilder build Batch
 	zki, err = bb.BuildBatch(coordIdxs, configBatch, oL1UserTxs, oL1CoordTxs, oL2Txs)
@@ -256,7 +256,7 @@ func TestTxSelectorBatchBuilderZKInputsMinimumFlow0(t *testing.T) {
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[1].Rollup.Batches[1].Batch.ForgeL1TxsNum])
 	// TxSelector select the transactions for the next Batch
 	coordIdxs, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs)
+		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs, nil)
 	require.NoError(t, err)
 	// BatchBuilder build Batch
 	zki, err = bb.BuildBatch(coordIdxs, configBatch, oL1UserTxs, oL1CoordTxs, oL2Txs)
@@ -319,7 +319,7 @@ func TestZKInputsExitWithFee0(t *testing.T) {
 	// TxSelector select the transactions for the next Batch
 	l1UserTxs := til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[1].Batch.ForgeL1TxsNum])
 	coordIdxs, _, oL1UserTxs, oL1CoordTxs, oL2Txs, _, err :=
-		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs)
+		txsel.GetL1L2TxSelection(txprocConfig, l1UserTxs, nil)
 	require.NoError(t, err)
 	// BatchBuilder build Batch
 	zki, err := bb.BuildBatch(coordIdxs, configBatch, oL1UserTxs, oL1CoordTxs, oL2Txs)
@@ -342,7 +342,7 @@ func TestZKInputsExitWithFee0(t *testing.T) {
 	require.NoError(t, err)
 	addL2Txs(t, l2DBTxSel, l2Txs) // Add L2s to TxSelector.L2DB
 	coordIdxs, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
-		txsel.GetL1L2TxSelection(txprocConfig, nil)
+		txsel.GetL1L2TxSelection(txprocConfig, nil, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 1, len(coordIdxs))
 	assert.Equal(t, 0, len(oL1UserTxs))

txselector/metrics.go

@@ -1,53 +0,0 @@
-package txselector
-
-import "github.com/prometheus/client_golang/prometheus"
-
-var (
-	metricGetL2TxSelection = prometheus.NewCounter(
-		prometheus.CounterOpts{
-			Name: "txsel_get_l2_txselecton_total",
-			Help: "",
-		},
-	)
-	metricGetL1L2TxSelection = prometheus.NewCounter(
-		prometheus.CounterOpts{
-			Name: "txsel_get_l1_l2_txselecton_total",
-			Help: "",
-		},
-	)
-
-	metricSelectedL1CoordinatorTxs = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "txsel_selected_l1_coordinator_txs",
-			Help: "",
-		},
-	)
-	metricSelectedL1UserTxs = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "txsel_selected_l1_user_txs",
-			Help: "",
-		},
-	)
-	metricSelectedL2Txs = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "txsel_selected_l2_txs",
-			Help: "",
-		},
-	)
-	metricDiscardedL2Txs = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "txsel_discarded_l2_txs",
-			Help: "",
-		},
-	)
-)
-
-func init() {
-	prometheus.MustRegister(metricGetL2TxSelection)
-	prometheus.MustRegister(metricGetL1L2TxSelection)
-
-	prometheus.MustRegister(metricSelectedL1CoordinatorTxs)
-	prometheus.MustRegister(metricSelectedL1UserTxs)
-	prometheus.MustRegister(metricSelectedL2Txs)
-	prometheus.MustRegister(metricDiscardedL2Txs)
-}

txselector/txselector.go

@@ -13,6 +13,7 @@ import (
 	"github.com/hermeznetwork/hermez-node/db/l2db"
 	"github.com/hermeznetwork/hermez-node/db/statedb"
 	"github.com/hermeznetwork/hermez-node/log"
+	"github.com/hermeznetwork/hermez-node/metric"
 	"github.com/hermeznetwork/hermez-node/txprocessor"
 	"github.com/hermeznetwork/tracerr"
 	"github.com/iden3/go-iden3-crypto/babyjub"
@@ -84,7 +85,7 @@ func (txsel *TxSelector) getCoordIdx(tokenID common.TokenID) (common.Idx, error)
 func (txsel *TxSelector) coordAccountForTokenID(l1CoordinatorTxs []common.L1Tx,
 	tokenID common.TokenID, positionL1 int) (*common.L1Tx, int, error) {
 	// check if CoordinatorAccount for TokenID is already pending to create
-	if checkAlreadyPendingToCreate(l1CoordinatorTxs, tokenID,
+	if checkPendingToCreateL1CoordTx(l1CoordinatorTxs, tokenID,
 		txsel.coordAccount.Addr, txsel.coordAccount.BJJ) {
 		return nil, positionL1, nil
 	}
@@ -121,11 +122,12 @@ func (txsel *TxSelector) coordAccountForTokenID(l1CoordinatorTxs []common.L1Tx,
 // but there is a transactions to them and the authorization of account
 // creation exists. The L1UserTxs, L1CoordinatorTxs, PoolL2Txs that will be
 // included in the next batch.
-func (txsel *TxSelector) GetL2TxSelection(selectionConfig txprocessor.Config) ([]common.Idx,
+func (txsel *TxSelector) GetL2TxSelection(selectionConfig txprocessor.Config, l1UserFutureTxs []common.L1Tx) ([]common.Idx,
 	[][]byte, []common.L1Tx, []common.PoolL2Tx, []common.PoolL2Tx, error) {
-	metricGetL2TxSelection.Inc()
+	metric.GetL2TxSelection.Inc()
 	coordIdxs, accCreationAuths, _, l1CoordinatorTxs, l2Txs,
-		discardedL2Txs, err := txsel.getL1L2TxSelection(selectionConfig, []common.L1Tx{})
+		discardedL2Txs, err := txsel.getL1L2TxSelection(selectionConfig,
+		[]common.L1Tx{}, l1UserFutureTxs)
 	return coordIdxs, accCreationAuths, l1CoordinatorTxs, l2Txs,
 		discardedL2Txs, tracerr.Wrap(err)
 }
@@ -139,11 +141,11 @@ func (txsel *TxSelector) GetL2TxSelection(selectionConfig txprocessor.Config) ([
 // creation exists. The L1UserTxs, L1CoordinatorTxs, PoolL2Txs that will be
 // included in the next batch.
 func (txsel *TxSelector) GetL1L2TxSelection(selectionConfig txprocessor.Config,
-	l1UserTxs []common.L1Tx) ([]common.Idx, [][]byte, []common.L1Tx,
+	l1UserTxs, l1UserFutureTxs []common.L1Tx) ([]common.Idx, [][]byte, []common.L1Tx,
 	[]common.L1Tx, []common.PoolL2Tx, []common.PoolL2Tx, error) {
-	metricGetL1L2TxSelection.Inc()
+	metric.GetL1L2TxSelection.Inc()
 	coordIdxs, accCreationAuths, l1UserTxs, l1CoordinatorTxs, l2Txs,
-		discardedL2Txs, err := txsel.getL1L2TxSelection(selectionConfig, l1UserTxs)
+		discardedL2Txs, err := txsel.getL1L2TxSelection(selectionConfig, l1UserTxs, l1UserFutureTxs)
 	return coordIdxs, accCreationAuths, l1UserTxs, l1CoordinatorTxs, l2Txs,
 		discardedL2Txs, tracerr.Wrap(err)
 }
@@ -157,7 +159,7 @@ func (txsel *TxSelector) GetL1L2TxSelection(selectionConfig txprocessor.Config,
 // creation exists. The L1UserTxs, L1CoordinatorTxs, PoolL2Txs that will be
 // included in the next batch.
 func (txsel *TxSelector) getL1L2TxSelection(selectionConfig txprocessor.Config,
-	l1UserTxs []common.L1Tx) ([]common.Idx, [][]byte, []common.L1Tx,
+	l1UserTxs, l1UserFutureTxs []common.L1Tx) ([]common.Idx, [][]byte, []common.L1Tx,
 	[]common.L1Tx, []common.PoolL2Tx, []common.PoolL2Tx, error) {
 	// WIP.0: the TxSelector is not optimized and will need a redesign. The
 	// current version is implemented in order to have a functional
@@ -221,10 +223,11 @@ func (txsel *TxSelector) getL1L2TxSelection(selectionConfig txprocessor.Config,
 			return nil, nil, nil, nil, nil, nil, tracerr.Wrap(err)
 		}
 
-		metricSelectedL1UserTxs.Set(float64(len(l1UserTxs)))
-		metricSelectedL1CoordinatorTxs.Set(0)
-		metricSelectedL2Txs.Set(0)
-		metricDiscardedL2Txs.Set(float64(len(discardedL2Txs)))
+		metric.SelectedL1UserTxs.Set(float64(len(l1UserTxs)))
+		metric.SelectedL1CoordinatorTxs.Set(0)
+		metric.SelectedL2Txs.Set(0)
+		metric.DiscardedL2Txs.Set(float64(len(discardedL2Txs)))
+
 		return nil, nil, l1UserTxs, nil, nil, discardedL2Txs, nil
 	}
 
@@ -233,7 +236,7 @@ func (txsel *TxSelector) getL1L2TxSelection(selectionConfig txprocessor.Config,
 	var validTxs, discardedL2Txs []common.PoolL2Tx
 	l2TxsForgable = sortL2Txs(l2TxsForgable)
 	accAuths, l1CoordinatorTxs, validTxs, discardedL2Txs, err =
-		txsel.processL2Txs(tp, selectionConfig, len(l1UserTxs),
+		txsel.processL2Txs(tp, selectionConfig, len(l1UserTxs), l1UserFutureTxs,
 			l2TxsForgable, validTxs, discardedL2Txs)
 	if err != nil {
 		return nil, nil, nil, nil, nil, nil, tracerr.Wrap(err)
@@ -247,8 +250,8 @@ func (txsel *TxSelector) getL1L2TxSelection(selectionConfig txprocessor.Config,
 		var l1CoordinatorTxs2 []common.L1Tx
 		accAuths2, l1CoordinatorTxs2, validTxs, discardedL2Txs, err =
 			txsel.processL2Txs(tp, selectionConfig,
-				len(l1UserTxs)+len(l1CoordinatorTxs), l2TxsNonForgable,
-				validTxs, discardedL2Txs)
+				len(l1UserTxs)+len(l1CoordinatorTxs), l1UserFutureTxs,
+				l2TxsNonForgable, validTxs, discardedL2Txs)
 		if err != nil {
 			return nil, nil, nil, nil, nil, nil, tracerr.Wrap(err)
 		}
@@ -320,17 +323,18 @@ func (txsel *TxSelector) getL1L2TxSelection(selectionConfig txprocessor.Config,
 		return nil, nil, nil, nil, nil, nil, tracerr.Wrap(err)
 	}
 
-	metricSelectedL1UserTxs.Set(float64(len(l1UserTxs)))
-	metricSelectedL1CoordinatorTxs.Set(float64(len(l1CoordinatorTxs)))
-	metricSelectedL2Txs.Set(float64(len(validTxs)))
-	metricDiscardedL2Txs.Set(float64(len(discardedL2Txs)))
+	metric.SelectedL1CoordinatorTxs.Set(float64(len(l1CoordinatorTxs)))
+	metric.SelectedL1UserTxs.Set(float64(len(l1UserTxs)))
+	metric.SelectedL2Txs.Set(float64(len(validTxs)))
+	metric.DiscardedL2Txs.Set(float64(len(discardedL2Txs)))
 
 	return coordIdxs, accAuths, l1UserTxs, l1CoordinatorTxs, validTxs, discardedL2Txs, nil
 }
 
 func (txsel *TxSelector) processL2Txs(tp *txprocessor.TxProcessor,
-	selectionConfig txprocessor.Config, nL1Txs int, l2Txs, validTxs, discardedL2Txs []common.PoolL2Tx) (
-	[][]byte, []common.L1Tx, []common.PoolL2Tx, []common.PoolL2Tx, error) {
+	selectionConfig txprocessor.Config, nL1Txs int, l1UserFutureTxs []common.L1Tx,
+	l2Txs, validTxs, discardedL2Txs []common.PoolL2Tx) ([][]byte, []common.L1Tx,
+	[]common.PoolL2Tx, []common.PoolL2Tx, error) {
 	var l1CoordinatorTxs []common.L1Tx
 	positionL1 := nL1Txs
 	var accAuths [][]byte
@@ -432,7 +436,8 @@ func (txsel *TxSelector) processL2Txs(tp *txprocessor.TxProcessor,
 		if l2Txs[i].ToIdx == 0 { // ToEthAddr/ToBJJ case
 			validL2Tx, l1CoordinatorTx, accAuth, err :=
 				txsel.processTxToEthAddrBJJ(validTxs, selectionConfig,
-					nL1Txs, l1CoordinatorTxs, positionL1, l2Txs[i])
+					nL1Txs, l1UserFutureTxs, l1CoordinatorTxs,
+					positionL1, l2Txs[i])
 			if err != nil {
 				log.Debugw("txsel.processTxToEthAddrBJJ", "err", err)
 				// Discard L2Tx, and update Info parameter of
@@ -572,18 +577,35 @@ func (txsel *TxSelector) processL2Txs(tp *txprocessor.TxProcessor,
 // l1CoordinatorTxs array, and then the PoolL2Tx is added into the validTxs
 // array.
 func (txsel *TxSelector) processTxToEthAddrBJJ(validTxs []common.PoolL2Tx,
-	selectionConfig txprocessor.Config, nL1UserTxs int, l1CoordinatorTxs []common.L1Tx,
-	positionL1 int, l2Tx common.PoolL2Tx) (*common.PoolL2Tx, *common.L1Tx,
-	*common.AccountCreationAuth, error) {
+	selectionConfig txprocessor.Config, nL1UserTxs int, l1UserFutureTxs,
+	l1CoordinatorTxs []common.L1Tx, positionL1 int, l2Tx common.PoolL2Tx) (
+	*common.PoolL2Tx, *common.L1Tx, *common.AccountCreationAuth, error) {
 	// if L2Tx needs a new L1CoordinatorTx of CreateAccount type, and a
 	// previous L2Tx in the current process already created a
 	// L1CoordinatorTx of this type, in the DB there still seem that needs
 	// to create a new L1CoordinatorTx, but as is already created, the tx
 	// is valid
-	if checkAlreadyPendingToCreate(l1CoordinatorTxs, l2Tx.TokenID, l2Tx.ToEthAddr, l2Tx.ToBJJ) {
+	if checkPendingToCreateL1CoordTx(l1CoordinatorTxs, l2Tx.TokenID, l2Tx.ToEthAddr, l2Tx.ToBJJ) {
 		return &l2Tx, nil, nil, nil
 	}
 
+	// check if L2Tx receiver account will be created by a L1UserFutureTxs
+	// (in the next batch, the current frozen queue). In that case, the L2Tx
+	// will be discarded at the current batch, even if there is an
+	// AccountCreationAuth for the account, as there is a L1UserTx in the
+	// frozen queue that will create the receiver Account.  The L2Tx is
+	// discarded to avoid the Coordinator creating a new L1CoordinatorTx to
+	// create the receiver account, which will be also created in the next
+	// batch from the L1UserFutureTx, ending with the user having 2
+	// different accounts for the same TokenID. The double account creation
+	// is supported by the Hermez zkRollup specification, but it was decided
+	// to mitigate it at the TxSelector level for the explained cases.
+	if checkPendingToCreateFutureTxs(l1UserFutureTxs, l2Tx.TokenID, l2Tx.ToEthAddr, l2Tx.ToBJJ) {
+		return nil, nil, nil, fmt.Errorf("L2Tx discarded at the current batch, as the" +
+			" receiver account does not exist yet, and there is a L1UserTx that" +
+			" will create that account in a future batch.")
+	}
+
 	var l1CoordinatorTx *common.L1Tx
 	var accAuth *common.AccountCreationAuth
 	if l2Tx.ToEthAddr != common.EmptyAddr && l2Tx.ToEthAddr != common.FFAddr {
@@ -686,7 +708,7 @@ func (txsel *TxSelector) processTxToEthAddrBJJ(validTxs []common.PoolL2Tx,
 	return &l2Tx, l1CoordinatorTx, accAuth, nil
 }
 
-func checkAlreadyPendingToCreate(l1CoordinatorTxs []common.L1Tx, tokenID common.TokenID,
+func checkPendingToCreateL1CoordTx(l1CoordinatorTxs []common.L1Tx, tokenID common.TokenID,
 	addr ethCommon.Address, bjj babyjub.PublicKeyComp) bool {
 	for i := 0; i < len(l1CoordinatorTxs); i++ {
 		if l1CoordinatorTxs[i].FromEthAddr == addr &&
@@ -698,6 +720,23 @@ func checkAlreadyPendingToCreate(l1CoordinatorTxs []common.L1Tx, tokenID common.
 	return false
 }
 
+func checkPendingToCreateFutureTxs(l1UserFutureTxs []common.L1Tx, tokenID common.TokenID,
+	addr ethCommon.Address, bjj babyjub.PublicKeyComp) bool {
+	for i := 0; i < len(l1UserFutureTxs); i++ {
+		if l1UserFutureTxs[i].FromEthAddr == addr &&
+			l1UserFutureTxs[i].TokenID == tokenID &&
+			l1UserFutureTxs[i].FromBJJ == bjj {
+			return true
+		}
+		if l1UserFutureTxs[i].FromEthAddr == addr &&
+			l1UserFutureTxs[i].TokenID == tokenID &&
+			common.EmptyBJJComp == bjj {
+			return true
+		}
+	}
+	return false
+}
+
 // sortL2Txs sorts the PoolL2Txs by AbsoluteFee and then by Nonce
 func sortL2Txs(l2Txs []common.PoolL2Tx) []common.PoolL2Tx {
 	// Sort by absolute fee with SliceStable, so that txs with same

txselector/txselector_test.go

@@ -182,7 +182,7 @@ func TestGetL2TxSelectionMinimumFlow0(t *testing.T) {
 	log.Debug("block:0 batch:1")
 	l1UserTxs := []common.L1Tx{}
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, _, err :=
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 0, len(oL1UserTxs))
 	assert.Equal(t, 0, len(oL1CoordTxs))
@@ -193,7 +193,7 @@ func TestGetL2TxSelectionMinimumFlow0(t *testing.T) {
 	log.Debug("block:0 batch:2")
 	l1UserTxs = []common.L1Tx{}
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, _, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 0, len(oL1UserTxs))
 	assert.Equal(t, 0, len(oL1CoordTxs))
@@ -204,7 +204,7 @@ func TestGetL2TxSelectionMinimumFlow0(t *testing.T) {
 	log.Debug("block:0 batch:3")
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[2].Batch.ForgeL1TxsNum])
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, _, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 2, len(oL1UserTxs))
 	assert.Equal(t, 0, len(oL1CoordTxs))
@@ -217,7 +217,7 @@ func TestGetL2TxSelectionMinimumFlow0(t *testing.T) {
 	log.Debug("block:0 batch:4")
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[3].Batch.ForgeL1TxsNum])
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, _, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 1, len(oL1UserTxs))
 	assert.Equal(t, 0, len(oL1CoordTxs))
@@ -231,7 +231,7 @@ func TestGetL2TxSelectionMinimumFlow0(t *testing.T) {
 	log.Debug("block:0 batch:5")
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[4].Batch.ForgeL1TxsNum])
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, _, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 0, len(oL1UserTxs))
 	assert.Equal(t, 0, len(oL1CoordTxs))
@@ -245,7 +245,7 @@ func TestGetL2TxSelectionMinimumFlow0(t *testing.T) {
 	log.Debug("block:0 batch:6")
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[5].Batch.ForgeL1TxsNum])
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, _, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 1, len(oL1UserTxs))
 	assert.Equal(t, 0, len(oL1CoordTxs))
@@ -279,7 +279,7 @@ func TestGetL2TxSelectionMinimumFlow0(t *testing.T) {
 	assert.True(t, l2TxsFromDB[1].VerifySignature(chainID, tc.Users["B"].BJJ.Public().Compress()))
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[6].Batch.ForgeL1TxsNum])
 	coordIdxs, accAuths, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, []common.Idx{261, 263}, coordIdxs)
 	assert.Equal(t, txsel.coordAccount.AccountCreationAuth, accAuths[0])
@@ -328,7 +328,7 @@ func TestGetL2TxSelectionMinimumFlow0(t *testing.T) {
 	assert.True(t, l2TxsFromDB[3].VerifySignature(chainID, tc.Users["A"].BJJ.Public().Compress()))
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[7].Batch.ForgeL1TxsNum])
 	coordIdxs, accAuths, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, []common.Idx{261, 263}, coordIdxs)
 	assert.Equal(t, 0, len(accAuths))
@@ -372,7 +372,7 @@ func TestGetL2TxSelectionMinimumFlow0(t *testing.T) {
 	assert.True(t, l2TxsFromDB[1].VerifySignature(chainID, tc.Users["B"].BJJ.Public().Compress()))
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[1].Rollup.Batches[0].Batch.ForgeL1TxsNum])
 	coordIdxs, accAuths, oL1UserTxs, oL1CoordTxs, oL2Txs, _, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, []common.Idx{263}, coordIdxs)
 	assert.Equal(t, 0, len(accAuths))
@@ -434,7 +434,7 @@ func TestPoolL2TxsWithoutEnoughBalance(t *testing.T) {
 	}
 	// batch1
 	l1UserTxs := []common.L1Tx{}
-	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	// 1st TransferToEthAddr
 	expectedTxID0 := "0x028847b86613c0b70be18c8622119ed045b42e4e47d7938fa90bb3d1dc14928965"
@@ -456,7 +456,7 @@ func TestPoolL2TxsWithoutEnoughBalance(t *testing.T) {
 
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[1].Batch.ForgeL1TxsNum])
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 3, len(oL1UserTxs))
 	assert.Equal(t, 0, len(oL1CoordTxs))
@@ -481,7 +481,7 @@ func TestPoolL2TxsWithoutEnoughBalance(t *testing.T) {
 
 	l1UserTxs = []common.L1Tx{}
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 0, len(oL1UserTxs))
 	assert.Equal(t, 0, len(oL1CoordTxs))
@@ -500,7 +500,7 @@ func TestPoolL2TxsWithoutEnoughBalance(t *testing.T) {
 	// initial PoolExit, which now is valid as B has enough Balance
 	l1UserTxs = []common.L1Tx{}
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 0, len(oL1UserTxs))
 	assert.Equal(t, 0, len(oL1CoordTxs))
@@ -550,7 +550,7 @@ func TestTransferToBjj(t *testing.T) {
 	// batch1 to freeze L1UserTxs that will create some accounts with
 	// positive balance
 	l1UserTxs := []common.L1Tx{}
-	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 
 	// Transfer is ToBJJ to a BJJ-only account that doesn't exist
@@ -568,7 +568,7 @@ func TestTransferToBjj(t *testing.T) {
 
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[1].Batch.ForgeL1TxsNum])
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 4, len(oL1UserTxs))
 	// We expect the coordinator to add an L1CoordTx to create an account for the recipient of the l2tx
@@ -595,7 +595,7 @@ func TestTransferToBjj(t *testing.T) {
 
 	l1UserTxs = []common.L1Tx{}
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 0, len(oL1UserTxs))
 	// Since the BJJ-only account B already exists, the coordinator doesn't add any L1CoordTxs
@@ -623,7 +623,7 @@ func TestTransferToBjj(t *testing.T) {
 
 	l1UserTxs = []common.L1Tx{}
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 0, len(oL1UserTxs))
 	// We expect the coordinator to add an L1CoordTx to create an account
@@ -678,7 +678,7 @@ func TestTransferManyFromSameAccount(t *testing.T) {
 	}
 	// batch1 to freeze L1UserTxs
 	l1UserTxs := []common.L1Tx{}
-	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 
 	// 8 transfers from the same account
@@ -710,7 +710,7 @@ func TestTransferManyFromSameAccount(t *testing.T) {
 	// transfers from account A
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[1].Batch.ForgeL1TxsNum])
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 3, len(oL1UserTxs))
 	require.Equal(t, 0, len(oL1CoordTxs))
@@ -760,7 +760,7 @@ func TestPoolL2TxInvalidNonces(t *testing.T) {
 	}
 	// batch1 to freeze L1UserTxs
 	l1UserTxs := []common.L1Tx{}
-	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 
 	batchPoolL2 := `
@@ -794,7 +794,7 @@ func TestPoolL2TxInvalidNonces(t *testing.T) {
 
 	// select L1 & L2 txs
 	_, accAuths, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	require.Equal(t, 3, len(oL1UserTxs))
 	require.Equal(t, 0, len(oL1CoordTxs))
@@ -809,7 +809,7 @@ func TestPoolL2TxInvalidNonces(t *testing.T) {
 	// batch 3
 	l1UserTxs = []common.L1Tx{}
 	_, accAuths, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 
 	require.Equal(t, 0, len(oL1UserTxs))
@@ -825,7 +825,7 @@ func TestPoolL2TxInvalidNonces(t *testing.T) {
 	// batch 4
 	l1UserTxs = []common.L1Tx{}
 	_, accAuths, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 
 	require.Equal(t, 0, len(oL1UserTxs))
@@ -873,10 +873,10 @@ func TestProcessL2Selection(t *testing.T) {
 	}
 	// batch1 to freeze L1UserTxs
 	l1UserTxs := []common.L1Tx{}
-	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 
-	// 8 transfers from the same account
+	// 3 transfers from the same account
 	batchPoolL2 := `
 	Type: PoolL2
 	PoolTransfer(0) A-B: 10 (126)
@@ -889,10 +889,10 @@ func TestProcessL2Selection(t *testing.T) {
 
 	// add the PoolL2Txs to the l2DB
 	addL2Txs(t, txsel, poolL2Txs)
-	// batch 2 to crate some accounts with positive balance, and do 8 L2Tx transfers from account A
+	// batch 2 to crate some accounts with positive balance, and do 3 L2Tx transfers from account A
 	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[1].Batch.ForgeL1TxsNum])
 	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	assert.Equal(t, 3, len(oL1UserTxs))
 	require.Equal(t, 0, len(oL1CoordTxs))
@@ -968,7 +968,7 @@ func TestValidTxsWithLowFeeAndInvalidTxsWithHighFee(t *testing.T) {
 	}
 	// batch1 to freeze L1UserTxs
 	l1UserTxs := []common.L1Tx{}
-	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 
 	// batch 2 to crate the accounts (from L1UserTxs)
@@ -976,7 +976,7 @@ func TestValidTxsWithLowFeeAndInvalidTxsWithHighFee(t *testing.T) {
 
 	// select L1 & L2 txs
 	_, accAuths, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 	require.Equal(t, 3, len(oL1UserTxs))
 	require.Equal(t, 0, len(oL1CoordTxs))
@@ -1014,7 +1014,7 @@ func TestValidTxsWithLowFeeAndInvalidTxsWithHighFee(t *testing.T) {
 	addL2Txs(t, txsel, poolL2Txs)
 	l1UserTxs = []common.L1Tx{}
 	_, accAuths, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 
 	require.Equal(t, 0, len(oL1UserTxs))
@@ -1029,7 +1029,7 @@ func TestValidTxsWithLowFeeAndInvalidTxsWithHighFee(t *testing.T) {
 
 	// batch 4. In this Batch, account B has enough balance to send the txs
 	_, accAuths, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
-		txsel.GetL1L2TxSelection(tpc, l1UserTxs)
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, nil)
 	require.NoError(t, err)
 
 	require.Equal(t, 0, len(oL1UserTxs))
@@ -1038,3 +1038,112 @@ func TestValidTxsWithLowFeeAndInvalidTxsWithHighFee(t *testing.T) {
 	require.Equal(t, 3, len(discardedL2Txs))
 	require.Equal(t, 0, len(accAuths))
 }
+
+func TestL1UserFutureTxs(t *testing.T) {
+	set := `
+		Type: Blockchain
+
+		CreateAccountDeposit(0) Coord: 0
+		CreateAccountDeposit(0) A: 100
+
+		> batchL1 // freeze L1User{2}
+		CreateAccountDeposit(0) B: 18
+		> batchL1 // forge L1User{2}, freeze L1User{1}
+		> batchL1 // forge L1User{1}
+		> block
+	`
+
+	chainID := uint16(0)
+	tc := til.NewContext(chainID, common.RollupConstMaxL1UserTx)
+	blocks, err := tc.GenerateBlocks(set)
+	assert.NoError(t, err)
+
+	hermezContractAddr := ethCommon.HexToAddress("0xc344E203a046Da13b0B4467EB7B3629D0C99F6E6")
+	txsel, _ := initTest(t, chainID, hermezContractAddr, tc.Users["Coord"])
+
+	// restart nonces of TilContext, as will be set by generating directly
+	// the PoolL2Txs for each specific batch with tc.GeneratePoolL2Txs
+	tc.RestartNonces()
+
+	tpc := txprocessor.Config{
+		NLevels:  16,
+		MaxFeeTx: 10,
+		MaxTx:    10,
+		MaxL1Tx:  10,
+		ChainID:  chainID,
+	}
+	// batch1 to freeze L1UserTxs
+	l1UserTxs := []common.L1Tx{}
+	l1UserFutureTxs := []common.L1Tx{}
+	_, _, _, _, _, _, err = txsel.GetL1L2TxSelection(tpc, l1UserTxs, l1UserFutureTxs)
+	require.NoError(t, err)
+
+	batchPoolL2 := `
+	Type: PoolL2
+	PoolTransferToEthAddr(0) A-B: 10 (126)
+	`
+	poolL2Txs, err := tc.GeneratePoolL2Txs(batchPoolL2)
+	require.NoError(t, err)
+	require.Equal(t, 1, len(poolL2Txs))
+
+	// add AccountCreationAuth for B
+	_ = addAccCreationAuth(t, tc, txsel, chainID, hermezContractAddr, "B")
+	// add the PoolL2Txs to the l2DB
+	addL2Txs(t, txsel, poolL2Txs)
+	// batch 2 to crate some accounts with positive balance, and do 1 L2Tx transfer from account A
+	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[1].Batch.ForgeL1TxsNum])
+	l1UserFutureTxs =
+		til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[2].Batch.ForgeL1TxsNum])
+	require.Equal(t, 2, len(l1UserTxs))
+	require.Equal(t, 1, len(l1UserFutureTxs))
+	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err :=
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, l1UserFutureTxs)
+	require.NoError(t, err)
+	assert.Equal(t, 2, len(oL1UserTxs))
+	require.Equal(t, 0, len(oL1CoordTxs))
+	// no L2Tx selected due the L1UserFutureTx, the L2Tx will be processed
+	// at the next batch once the L1UserTx of CreateAccount B is processed,
+	// despite that there is an AccountCreationAuth for Account B.
+	assert.Equal(t, 0, len(oL2Txs))
+	assert.Equal(t, 1, len(discardedL2Txs))
+	assert.Equal(t, "Tx not selected (in processTxToEthAddrBJJ) due to L2Tx"+
+		" discarded at the current batch, as the receiver account does"+
+		" not exist yet, and there is a L1UserTx that will create that"+
+		" account in a future batch.",
+		discardedL2Txs[0].Info)
+
+	err = txsel.l2db.StartForging(common.TxIDsFromPoolL2Txs(oL2Txs),
+		txsel.localAccountsDB.CurrentBatch())
+	require.NoError(t, err)
+
+	l1UserTxs = til.L1TxsToCommonL1Txs(tc.Queues[*blocks[0].Rollup.Batches[2].Batch.ForgeL1TxsNum])
+	l1UserFutureTxs = []common.L1Tx{}
+	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
+		txsel.GetL1L2TxSelection(tpc, l1UserTxs, l1UserFutureTxs)
+	require.NoError(t, err)
+	assert.Equal(t, 1, len(oL1UserTxs))
+	require.Equal(t, 0, len(oL1CoordTxs))
+	// L2Tx selected as now the L1UserTx of CreateAccount B is processed
+	assert.Equal(t, 1, len(oL2Txs))
+	assert.Equal(t, 0, len(discardedL2Txs))
+	err = txsel.l2db.StartForging(common.TxIDsFromPoolL2Txs(oL2Txs),
+		txsel.localAccountsDB.CurrentBatch())
+	require.NoError(t, err)
+
+	// generate a new L2Tx A-B and check that is processed
+	poolL2Txs, err = tc.GeneratePoolL2Txs(batchPoolL2)
+	require.NoError(t, err)
+	require.Equal(t, 1, len(poolL2Txs))
+	// add the PoolL2Txs to the l2DB
+	addL2Txs(t, txsel, poolL2Txs)
+	_, _, oL1UserTxs, oL1CoordTxs, oL2Txs, discardedL2Txs, err =
+		txsel.GetL1L2TxSelection(tpc, nil, nil)
+	require.NoError(t, err)
+	assert.Equal(t, 0, len(oL1UserTxs))
+	require.Equal(t, 0, len(oL1CoordTxs))
+	assert.Equal(t, 1, len(oL2Txs))
+	assert.Equal(t, 0, len(discardedL2Txs))
+	err = txsel.l2db.StartForging(common.TxIDsFromPoolL2Txs(oL2Txs),
+		txsel.localAccountsDB.CurrentBatch())
+	require.NoError(t, err)
+}