sharding: improve coverage for #100

Former-commit-id: 59b4763

sharding/collation.go

@@ -37,6 +37,12 @@ type collationHeaderData struct {
 	ProposerSignature []byte          // the proposer's signature for calculating collation hash.
 }
 
+// NewCollation initializes a collation and leaves it up to clients to serialize, deserialize
+// and provide the body and transactions upon creation.
+func NewCollation(header *CollationHeader, body []byte, transactions []*types.Transaction) *Collation {
+	return &Collation{header, body, transactions}
+}
+
 // NewCollationHeader initializes a collation header struct.
 func NewCollationHeader(shardID *big.Int, chunkRoot *common.Hash, period *big.Int, proposerAddress *common.Address, proposerSignature []byte) *CollationHeader {
 	data := collationHeaderData{
@@ -94,12 +100,6 @@ func (c *Collation) ProposerAddress() *common.Address {
 	return c.header.data.ProposerAddress
 }
 
-// AddTransaction adds to the collation's body of tx blobs.
-func (c *Collation) AddTransaction(tx *types.Transaction) {
-	// TODO: Include blob serialization instead.
-	c.transactions = append(c.transactions, tx)
-}
-
 // CalculateChunkRoot updates the collation header's chunk root based on the body.
 func (c *Collation) CalculateChunkRoot() {
 	// TODO: this needs to be based on blob serialization.

sharding/collation_test.go

@@ -1,48 +1,80 @@
 package sharding
 
 import (
+	"math/big"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 )
 
-// TODO: this test needs to change as we will be serializing tx's into blobs
-// within the collation body instead.
-
-func TestCollation_AddTransactions(t *testing.T) {
-	tests := []struct {
-		transactions []*types.Transaction
-	}{
-		{
-			transactions: []*types.Transaction{
-				makeTxWithGasLimit(0),
-				makeTxWithGasLimit(1),
-				makeTxWithGasLimit(2),
-				makeTxWithGasLimit(3),
-			},
-		}, {
-			transactions: []*types.Transaction{},
-		},
+func TestCollation_Transactions(t *testing.T) {
+	header := NewCollationHeader(big.NewInt(1), nil, big.NewInt(1), nil, []byte{})
+	body := []byte{}
+	transactions := []*types.Transaction{
+		makeTxWithGasLimit(0),
+		makeTxWithGasLimit(1),
+		makeTxWithGasLimit(2),
+		makeTxWithGasLimit(3),
 	}
 
-	for _, tt := range tests {
-		c := &Collation{}
-		for _, tx := range tt.transactions {
-			c.AddTransaction(tx)
-		}
-		results := c.Transactions()
-		if len(results) != len(tt.transactions) {
-			t.Fatalf("Wrong number of transactions. want=%d. got=%d", len(tt.transactions), len(results))
-		}
-		for i, tx := range tt.transactions {
-			if results[i] != tx {
-				t.Fatalf("Mismatched transactions. wanted=%+v. got=%+v", tt.transactions, results)
-			}
+	collation := NewCollation(header, body, transactions)
+
+	for i, tx := range collation.Transactions() {
+		if tx.Hash().String() != transactions[i].Hash().String() {
+			t.Errorf("initialized collation struct does not contain correct transactions")
 		}
 	}
 }
 
+func TestCollation_ProposerAddress(t *testing.T) {
+	proposerAddr := common.StringToAddress("proposer")
+	header := NewCollationHeader(big.NewInt(1), nil, big.NewInt(1), &proposerAddr, []byte{})
+	body := []byte{}
+
+	collation := NewCollation(header, body, nil)
+
+	if collation.ProposerAddress().String() != proposerAddr.String() {
+		t.Errorf("initialized collation does not contain correct proposer address")
+	}
+}
+
+// TODO: this test needs to change as we will be serializing tx's into blobs
+// within the collation body instead.
+
+// func TestCollation_AddTransactions(t *testing.T) {
+// 	tests := []struct {
+// 		transactions []*types.Transaction
+// 	}{
+// 		{
+// 			transactions: []*types.Transaction{
+// 				makeTxWithGasLimit(0),
+// 				makeTxWithGasLimit(1),
+// 				makeTxWithGasLimit(2),
+// 				makeTxWithGasLimit(3),
+// 			},
+// 		}, {
+// 			transactions: []*types.Transaction{},
+// 		},
+// 	}
+
+// 	for _, tt := range tests {
+// 		c := &Collation{}
+// 		for _, tx := range tt.transactions {
+// 			c.AddTransaction(tx)
+// 		}
+// 		results := c.Transactions()
+// 		if len(results) != len(tt.transactions) {
+// 			t.Fatalf("Wrong number of transactions. want=%d. got=%d", len(tt.transactions), len(results))
+// 		}
+// 		for i, tx := range tt.transactions {
+// 			if results[i] != tx {
+// 				t.Fatalf("Mismatched transactions. wanted=%+v. got=%+v", tt.transactions, results)
+// 			}
+// 		}
+// 	}
+// }
+
 func makeTxWithGasLimit(gl uint64) *types.Transaction {
 	return types.NewTransaction(0 /*nonce*/, common.HexToAddress("0x0") /*to*/, nil /*amount*/, gl, nil /*gasPrice*/, nil /*data*/)
 }

sharding/database/inmemory.go

@@ -14,8 +14,8 @@ type ShardKV struct {
 	kv map[common.Hash][]byte
 }
 
-// MakeShardKV initializes a keyval store in memory.
-func MakeShardKV() *ShardKV {
+// NewShardKV initializes a keyval store in memory.
+func NewShardKV() *ShardKV {
 	return &ShardKV{kv: make(map[common.Hash][]byte)}
 }
 

sharding/database/inmemory_test.go

@@ -7,7 +7,7 @@ import (
 )
 
 func Test_ShardKVPut(t *testing.T) {
-	kv := MakeShardKV()
+	kv := NewShardKV()
 	hash := common.StringToHash("ralph merkle")
 
 	if err := kv.Put(hash, []byte{1, 2, 3}); err != nil {
@@ -16,7 +16,7 @@ func Test_ShardKVPut(t *testing.T) {
 }
 
 func Test_ShardKVHas(t *testing.T) {
-	kv := MakeShardKV()
+	kv := NewShardKV()
 	hash := common.StringToHash("ralph merkle")
 
 	if err := kv.Put(hash, []byte{1, 2, 3}); err != nil {
@@ -34,7 +34,7 @@ func Test_ShardKVHas(t *testing.T) {
 }
 
 func Test_ShardKVGet(t *testing.T) {
-	kv := MakeShardKV()
+	kv := NewShardKV()
 	hash := common.StringToHash("ralph merkle")
 
 	if err := kv.Put(hash, []byte{1, 2, 3}); err != nil {
@@ -57,7 +57,7 @@ func Test_ShardKVGet(t *testing.T) {
 }
 
 func Test_ShardKVDelete(t *testing.T) {
-	kv := MakeShardKV()
+	kv := NewShardKV()
 	hash := common.StringToHash("ralph merkle")
 
 	if err := kv.Put(hash, []byte{1, 2, 3}); err != nil {

sharding/shard.go

@@ -22,8 +22,8 @@ type Shard struct {
 	shardID *big.Int
 }
 
-// MakeShard creates an instance of a Shard struct given a shardID.
-func MakeShard(shardID *big.Int, shardDB shardBackend) *Shard {
+// NewShard creates an instance of a Shard struct given a shardID.
+func NewShard(shardID *big.Int, shardDB shardBackend) *Shard {
 	return &Shard{
 		shardID: shardID,
 		shardDB: shardDB,
@@ -66,15 +66,15 @@ func (s *Shard) CollationByHash(headerHash *common.Hash) (*Collation, error) {
 	if err != nil {
 		return nil, err
 	}
-	if header == nil {
-		return nil, fmt.Errorf("header not found")
-	}
 
 	body, err := s.BodyByChunkRoot(header.ChunkRoot())
 	if err != nil {
 		return nil, err
 	}
-	return &Collation{header: header, body: body}, nil
+	// TODO: deserializes the body into a tx's object instead of using
+	// nil as the third arg to MakeCollation.
+	col := NewCollation(header, body, nil)
+	return col, nil
 }
 
 // CanonicalHeaderHash gets a collation header hash that has been set as
@@ -104,8 +104,12 @@ func (s *Shard) CanonicalHeaderHash(shardID *big.Int, period *big.Int) (*common.
 func (s *Shard) CanonicalCollation(shardID *big.Int, period *big.Int) (*Collation, error) {
 	h, err := s.CanonicalHeaderHash(shardID, period)
 	if err != nil {
-		return nil, fmt.Errorf("hash not found: %v", err)
+		return nil, fmt.Errorf("error while getting canoncial header hash: %v", err)
 	}
+	if h == nil {
+		return nil, fmt.Errorf("header not found")
+	}
+
 	collation, err := s.CollationByHash(h)
 	if err != nil {
 		return nil, fmt.Errorf("no canonical collation found for hash: %v", err)

sharding/shard_test.go

@@ -22,15 +22,15 @@ func TestShard_ValidateShardID(t *testing.T) {
 	emptyHash := common.StringToHash("")
 	emptyAddr := common.StringToAddress("")
 	header := NewCollationHeader(big.NewInt(1), &emptyHash, big.NewInt(1), &emptyAddr, []byte{})
-	shardDB := database.MakeShardKV()
-	shard := MakeShard(big.NewInt(3), shardDB)
+	shardDB := database.NewShardKV()
+	shard := NewShard(big.NewInt(3), shardDB)
 
 	if err := shard.ValidateShardID(header); err == nil {
 		t.Errorf("ShardID validation incorrect. Function should throw error when ShardID's do not match. want=%d. got=%d", header.ShardID().Int64(), shard.ShardID().Int64())
 	}
 
 	header2 := NewCollationHeader(big.NewInt(100), &emptyHash, big.NewInt(1), &emptyAddr, []byte{})
-	shard2 := MakeShard(big.NewInt(100), shardDB)
+	shard2 := NewShard(big.NewInt(100), shardDB)
 
 	if err := shard2.ValidateShardID(header2); err != nil {
 		t.Errorf("ShardID validation incorrect. Function should not throw error when ShardID's match. want=%d. got=%d", header2.ShardID().Int64(), shard2.ShardID().Int64())
@@ -41,8 +41,8 @@ func TestShard_HeaderByHash(t *testing.T) {
 	emptyHash := common.StringToHash("")
 	emptyAddr := common.StringToAddress("")
 	header := NewCollationHeader(big.NewInt(1), &emptyHash, big.NewInt(1), &emptyAddr, []byte{})
-	shardDB := database.MakeShardKV()
-	shard := MakeShard(big.NewInt(1), shardDB)
+	shardDB := database.NewShardKV()
+	shard := NewShard(big.NewInt(1), shardDB)
 
 	if err := shard.SaveHeader(header); err != nil {
 		t.Fatalf("cannot save collation header: %v", err)
@@ -70,16 +70,25 @@ func TestShard_CollationByHash(t *testing.T) {
 		body:   []byte{1, 2, 3},
 	}
 
+	// TODO: check if body by chunk root fails!
+
 	// We set the chunk root.
 	collation.CalculateChunkRoot()
 
-	shardDB := database.MakeShardKV()
-	shard := MakeShard(big.NewInt(1), shardDB)
+	shardDB := database.NewShardKV()
+	shard := NewShard(big.NewInt(1), shardDB)
+
+	hash := collation.Header().Hash()
+
+	// should not be able to fetch collation without saving first.
+	_, err := shard.CollationByHash(&hash)
+	if err == nil {
+		t.Errorf("should not be able to fetch collation before saving first")
+	}
 
 	if err := shard.SaveCollation(collation); err != nil {
 		t.Fatalf("cannot save collation: %v", err)
 	}
-	hash := collation.Header().Hash()
 
 	dbCollation, err := shard.CollationByHash(&hash)
 	if err != nil {
@@ -100,8 +109,13 @@ func TestShard_CanonicalHeaderHash(t *testing.T) {
 	emptyHash := common.StringToHash("")
 	header := NewCollationHeader(shardID, &emptyHash, period, &proposerAddress, proposerSignature)
 
-	shardDB := database.MakeShardKV()
-	shard := MakeShard(shardID, shardDB)
+	shardDB := database.NewShardKV()
+	shard := NewShard(shardID, shardDB)
+
+	// should not be able to set as canonical before saving the header.
+	if err := shard.SetCanonical(header); err == nil {
+		t.Errorf("cannot set as canonical before saving header first")
+	}
 
 	if err := shard.SaveHeader(header); err != nil {
 		t.Fatalf("failed to save header to shardDB: %v", err)
@@ -131,8 +145,9 @@ func TestShard_CanonicalCollation(t *testing.T) {
 	emptyHash := common.StringToHash("")
 	header := NewCollationHeader(shardID, &emptyHash, period, &proposerAddress, proposerSignature)
 
-	shardDB := database.MakeShardKV()
-	shard := MakeShard(shardID, shardDB)
+	shardDB := database.NewShardKV()
+	shard := NewShard(shardID, shardDB)
+	otherShard := NewShard(big.NewInt(2), shardDB)
 
 	collation := &Collation{
 		header: header,
@@ -150,6 +165,11 @@ func TestShard_CanonicalCollation(t *testing.T) {
 		t.Fatalf("failed to set header as canonical: %v", err)
 	}
 
+	// should not be allowed to set as canonical in a different shard.
+	if err := otherShard.SetCanonical(header); err == nil {
+		t.Errorf("should not be able to set header with ShardID=%v as canonical in other shard=%v", header.ShardID(), big.NewInt(2))
+	}
+
 	canonicalCollation, err := shard.CanonicalCollation(shardID, period)
 	if err != nil {
 		t.Fatalf("failed to get canonical collation from shardDB: %v", err)
@@ -162,8 +182,8 @@ func TestShard_CanonicalCollation(t *testing.T) {
 func TestShard_BodyByChunkRoot(t *testing.T) {
 	body := []byte{1, 2, 3, 4, 5}
 	shardID := big.NewInt(1)
-	shardDB := database.MakeShardKV()
-	shard := MakeShard(shardID, shardDB)
+	shardDB := database.NewShardKV()
+	shard := NewShard(shardID, shardDB)
 
 	if err := shard.SaveBody(body); err != nil {
 		t.Fatalf("cannot save body: %v", err)
@@ -192,8 +212,8 @@ func TestShard_CheckAvailability(t *testing.T) {
 	emptyHash := common.StringToHash("")
 	header := NewCollationHeader(shardID, &emptyHash, period, &proposerAddress, proposerSignature)
 
-	shardDB := database.MakeShardKV()
-	shard := MakeShard(shardID, shardDB)
+	shardDB := database.NewShardKV()
+	shard := NewShard(shardID, shardDB)
 
 	collation := &Collation{
 		header: header,
@@ -215,3 +235,27 @@ func TestShard_CheckAvailability(t *testing.T) {
 		t.Errorf("collation body is not available: chunkRoot=%v, body=%v", header.ChunkRoot(), collation.body)
 	}
 }
+
+func TestShard_SaveCollation(t *testing.T) {
+	headerShardID := big.NewInt(1)
+	period := big.NewInt(1)
+	proposerAddress := common.StringToAddress("")
+	proposerSignature := []byte{}
+	emptyHash := common.StringToHash("")
+	header := NewCollationHeader(headerShardID, &emptyHash, period, &proposerAddress, proposerSignature)
+
+	shardDB := database.NewShardKV()
+	shard := NewShard(big.NewInt(2), shardDB)
+
+	collation := &Collation{
+		header: header,
+		body:   []byte{1, 2, 3},
+	}
+
+	// We set the chunk root.
+	collation.CalculateChunkRoot()
+
+	if err := shard.SaveCollation(collation); err == nil {
+		t.Errorf("cannot save collation in shard with wrong shardID")
+	}
+}