From d803c225ab1b1b721d63b519d1006ad97509717a Mon Sep 17 00:00:00 2001
From: Alejandro Lopez <a.lopez@yadro.com>
Date: Mon, 15 May 2023 14:46:17 +0300
Subject: [PATCH] [#341] Register candidates in separate transactions

Signed-off-by: Alejandro Lopez <a.lopez@yadro.com>
---
 .../modules/morph/initialize_register.go      | 72 ++++++++++++-------
 .../internal/modules/morph/initialize_test.go |  6 ++
 2 files changed, 54 insertions(+), 24 deletions(-)

diff --git a/cmd/frostfs-adm/internal/modules/morph/initialize_register.go b/cmd/frostfs-adm/internal/modules/morph/initialize_register.go
index b1542cc92..469b269de 100644
--- a/cmd/frostfs-adm/internal/modules/morph/initialize_register.go
+++ b/cmd/frostfs-adm/internal/modules/morph/initialize_register.go
@@ -19,33 +19,24 @@ import (
 )
 
 // initialAlphabetNEOAmount represents the total amount of GAS distributed between alphabet nodes.
-const initialAlphabetNEOAmount = native.NEOTotalSupply
-
-func (c *initializeContext) registerCandidates() error {
-	neoHash := neo.Hash
-
-	cc, err := unwrap.Array(c.ReadOnlyInvoker.Call(neoHash, "getCandidates"))
-	if err != nil {
-		return fmt.Errorf("`getCandidates`: %w", err)
-	}
-
-	if len(cc) > 0 {
-		c.Command.Println("Candidates are already registered.")
-		return nil
-	}
+const (
+	initialAlphabetNEOAmount = native.NEOTotalSupply
+	registerBatchSize        = transaction.MaxAttributes - 1
+)
 
+func (c *initializeContext) registerCandidateRange(start, end int) error {
 	regPrice, err := c.getCandidateRegisterPrice()
 	if err != nil {
 		return fmt.Errorf("can't fetch registration price: %w", err)
 	}
 
 	w := io.NewBufBinWriter()
-	emit.AppCall(w.BinWriter, neoHash, "setRegisterPrice", callflag.States, 1)
-	for _, acc := range c.Accounts {
-		emit.AppCall(w.BinWriter, neoHash, "registerCandidate", callflag.States, acc.PrivateKey().PublicKey().Bytes())
+	emit.AppCall(w.BinWriter, neo.Hash, "setRegisterPrice", callflag.States, 1)
+	for _, acc := range c.Accounts[start:end] {
+		emit.AppCall(w.BinWriter, neo.Hash, "registerCandidate", callflag.States, acc.PrivateKey().PublicKey().Bytes())
 		emit.Opcodes(w.BinWriter, opcode.ASSERT)
 	}
-	emit.AppCall(w.BinWriter, neoHash, "setRegisterPrice", callflag.States, regPrice)
+	emit.AppCall(w.BinWriter, neo.Hash, "setRegisterPrice", callflag.States, regPrice)
 	if w.Err != nil {
 		panic(fmt.Sprintf("BUG: %v", w.Err))
 	}
@@ -54,14 +45,14 @@ func (c *initializeContext) registerCandidates() error {
 		Signer:  c.getSigner(false, c.CommitteeAcc),
 		Account: c.CommitteeAcc,
 	}}
-	for i := range c.Accounts {
+	for _, acc := range c.Accounts[start:end] {
 		signers = append(signers, rpcclient.SignerAccount{
 			Signer: transaction.Signer{
-				Account:          c.Accounts[i].Contract.ScriptHash(),
+				Account:          acc.Contract.ScriptHash(),
 				Scopes:           transaction.CustomContracts,
-				AllowedContracts: []util.Uint160{neoHash},
+				AllowedContracts: []util.Uint160{neo.Hash},
 			},
-			Account: c.Accounts[i],
+			Account: acc,
 		})
 	}
 
@@ -74,8 +65,8 @@ func (c *initializeContext) registerCandidates() error {
 	}
 
 	network := c.CommitteeAct.GetNetwork()
-	for i := range c.Accounts {
-		if err := c.Accounts[i].SignTx(network, tx); err != nil {
+	for _, acc := range c.Accounts[start:end] {
+		if err := acc.SignTx(network, tx); err != nil {
 			return fmt.Errorf("can't sign a transaction: %w", err)
 		}
 	}
@@ -83,6 +74,39 @@ func (c *initializeContext) registerCandidates() error {
 	return c.sendTx(tx, c.Command, true)
 }
 
+func (c *initializeContext) registerCandidates() error {
+	cc, err := unwrap.Array(c.ReadOnlyInvoker.Call(neo.Hash, "getCandidates"))
+	if err != nil {
+		return fmt.Errorf("`getCandidates`: %w", err)
+	}
+
+	need := len(c.Accounts)
+	have := len(cc)
+
+	if need == have {
+		c.Command.Println("Candidates are already registered.")
+		return nil
+	}
+
+	// Register candidates in batches in order to overcome the signers amount limit.
+	// See: https://github.com/nspcc-dev/neo-go/blob/master/pkg/core/transaction/transaction.go#L27
+	for i := 0; i < need; i += registerBatchSize {
+		start, end := i, i+registerBatchSize
+		if end > need {
+			end = need
+		}
+		// This check is sound because transactions are accepted/rejected atomically.
+		if have >= end {
+			continue
+		}
+		if err := c.registerCandidateRange(start, end); err != nil {
+			return fmt.Errorf("registering candidates %d..%d: %q", start, end-1, err)
+		}
+	}
+
+	return nil
+}
+
 func (c *initializeContext) transferNEOToAlphabetContracts() error {
 	neoHash := neo.Hash
 
diff --git a/cmd/frostfs-adm/internal/modules/morph/initialize_test.go b/cmd/frostfs-adm/internal/modules/morph/initialize_test.go
index fb2dc3e3f..e2e5aa0ad 100644
--- a/cmd/frostfs-adm/internal/modules/morph/initialize_test.go
+++ b/cmd/frostfs-adm/internal/modules/morph/initialize_test.go
@@ -37,6 +37,12 @@ func TestInitialize(t *testing.T) {
 	t.Run("7 nodes", func(t *testing.T) {
 		testInitialize(t, 7)
 	})
+	t.Run("16 nodes", func(t *testing.T) {
+		testInitialize(t, 16)
+	})
+	t.Run("22 nodes", func(t *testing.T) {
+		testInitialize(t, 22)
+	})
 }
 
 func testInitialize(t *testing.T, committeeSize int) {