Merge pull request #53 from 8thlight/introduce-repository

Extract Postgres repository

observers/blockchain_db_observer.go

@@ -2,8 +2,8 @@ package observers
 
 import (
 	"github.com/8thlight/vulcanizedb/core"
+	"github.com/8thlight/vulcanizedb/repositories"
 	"github.com/jmoiron/sqlx"
-	_ "github.com/lib/pq"
 )
 
 type BlockchainDBObserver struct {
@@ -11,25 +11,5 @@ type BlockchainDBObserver struct {
 }
 
 func (observer BlockchainDBObserver) NotifyBlockAdded(block core.Block) {
-	insertedBlockId := saveBlock(observer, block)
+	repositories.NewPostgres(observer.Db).CreateBlock(block)
-	saveTransactions(insertedBlockId, block.Transactions, observer)
-}
-
-func saveBlock(observer BlockchainDBObserver, block core.Block) int64 {
-	insertedBlock := observer.Db.QueryRow(
-		"Insert INTO blocks "+
-		"(block_number, block_gaslimit, block_gasused, block_time, block_difficulty, block_hash, block_nonce, block_parenthash, block_size, uncle_hash) "+
-		"VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10) RETURNING id",
-		block.Number, block.GasLimit, block.GasUsed, block.Time, block.Difficulty, block.Hash, block.Nonce, block.ParentHash, block.Size, block.UncleHash)
-	var blockId int64
-	insertedBlock.Scan(&blockId)
-	return blockId
-}
-
-func saveTransactions(blockId int64, transactions []core.Transaction, observer BlockchainDBObserver) {
-	for _, transaction := range transactions {
-		observer.Db.MustExec("Insert INTO transactions "+
-			"(block_id, tx_hash, tx_nonce, tx_to, tx_gaslimit, tx_gasprice, tx_value) VALUES ($1, $2, $3, $4, $5, $6, $7)",
-			blockId, transaction.Hash, transaction.Nonce, transaction.To, transaction.GasLimit, transaction.GasPrice, transaction.Value)
-	}
 }

observers/blockchain_db_observer_test.go

@@ -6,6 +6,7 @@ import (
 	"github.com/8thlight/vulcanizedb/config"
 	"github.com/8thlight/vulcanizedb/core"
 	"github.com/8thlight/vulcanizedb/observers"
+	"github.com/8thlight/vulcanizedb/repositories"
 	"github.com/jmoiron/sqlx"
 	_ "github.com/lib/pq"
 	. "github.com/onsi/ginkgo"
@@ -38,180 +39,19 @@ var _ = Describe("Saving blocks to the database", func() {
 		Expect(observer).NotTo(BeNil())
 	})
 
-	It("connects to the database", func() {
+	It("saves a block with one transaction", func() {
-		Expect(err).Should(BeNil())
-		Expect(db).ShouldNot(BeNil())
-	})
-
-	It("starts with no blocks", func() {
-		var count int
-		queryError := db.Get(&count, "SELECT COUNT(*) FROM blocks")
-		Expect(queryError).Should(BeNil())
-		Expect(count).Should(Equal(0))
-	})
-
-	It("inserts a block", func() {
-		// setup a block in memory
-		blockNumber := int64(123)
-		gasLimit := int64(1000000)
-		gasUsed := int64(10)
-		blockHash := "x123"
-		blockParentHash := "x456"
-		blockNonce := "0x881db2ca900682e9a9"
-		blockTime := int64(1508981640)
-		uncleHash := "x789"
-		blockSize := int64(1000)
-		difficulty := int64(10)
 		block := core.Block{
-			Difficulty: difficulty,
+			Number:       123,
-			GasLimit:   gasLimit,
+			Transactions: []core.Transaction{{}},
-			GasUsed:    gasUsed,
-			Hash:       blockHash,
-			Nonce:      blockNonce,
-			Number:     blockNumber,
-			ParentHash: blockParentHash,
-			Size:       blockSize,
-			Time:       blockTime,
-			UncleHash:  uncleHash,
-		}
-
-		// save the block to the database
-		observer := observers.BlockchainDBObserver{Db: db}
-		observer.NotifyBlockAdded(block)
-
-		// find the saved block
-		rows, err := db.Query(
-			"SELECT  block_number, block_gaslimit, block_gasused, block_time, block_difficulty, block_hash, block_nonce, block_parenthash, block_size, uncle_hash FROM blocks")
-		Expect(err).To(BeNil())
-		var savedBlocks []core.Block
-		for rows.Next() {
-			var blockHash string
-			var blockNonce string
-			var blockNumber int64
-			var blockParentHash string
-			var blockSize int64
-			var blockTime float64
-			var difficulty int64
-			var gasLimit float64
-			var gasUsed float64
-			var uncleHash string
-			rows.Scan(&blockNumber, &gasLimit, &gasUsed, &blockTime, &difficulty, &blockHash, &blockNonce, &blockParentHash, &blockSize, &uncleHash)
-			savedBlock := core.Block{
-				Difficulty: difficulty,
-				GasLimit:   int64(gasLimit),
-				GasUsed:    int64(gasUsed),
-				Hash:       blockHash,
-				Nonce:      blockNonce,
-				Number:     blockNumber,
-				ParentHash: blockParentHash,
-				Size:       blockSize,
-				Time:       int64(blockTime),
-				UncleHash:  uncleHash,
-			}
-			savedBlocks = append(savedBlocks, savedBlock)
-		}
-		// assert against the attributes
-		Expect(len(savedBlocks)).To(Equal(1))
-		Expect(savedBlocks[0].Difficulty).To(Equal(difficulty))
-		Expect(savedBlocks[0].GasLimit).To(Equal(gasLimit))
-		Expect(savedBlocks[0].GasUsed).To(Equal(gasUsed))
-		Expect(savedBlocks[0].Hash).To(Equal(blockHash))
-		Expect(savedBlocks[0].Nonce).To(Equal(blockNonce))
-		Expect(savedBlocks[0].Number).To(Equal(blockNumber))
-		Expect(savedBlocks[0].ParentHash).To(Equal(blockParentHash))
-		Expect(savedBlocks[0].Size).To(Equal(blockSize))
-		Expect(savedBlocks[0].Time).To(Equal(blockTime))
-		Expect(savedBlocks[0].UncleHash).To(Equal(uncleHash))
-	})
-
-	var _ = Describe("Saving transactions to the database", func() {
-
-		It("inserts a transaction", func() {
-			gasLimit := int64(5000)
-			gasPrice := int64(3)
-			nonce := uint64(10000)
-			to := "1234567890"
-			value := int64(10)
-
-			txRecord := core.Transaction{
-				Hash:     "x1234",
-				GasPrice: gasPrice,
-				GasLimit: gasLimit,
-				Nonce:    nonce,
-				To:       to,
-				Value:    value,
-			}
-			block := core.Block{Transactions: []core.Transaction{txRecord}}
-
-			observer := observers.BlockchainDBObserver{Db: db}
-			observer.NotifyBlockAdded(block)
-
-			rows, err := db.Query("SELECT tx_hash, tx_nonce, tx_to, tx_gaslimit, tx_gasprice, tx_value FROM transactions")
-			Expect(err).To(BeNil())
-
-			var savedTransactions []core.Transaction
-			for rows.Next() {
-				var dbHash string
-				var dbNonce uint64
-				var dbTo string
-				var dbGasLimit int64
-				var dbGasPrice int64
-				var dbValue int64
-				rows.Scan(&dbHash, &dbNonce, &dbTo, &dbGasLimit, &dbGasPrice, &dbValue)
-				savedTransaction := core.Transaction{
-					GasLimit: dbGasLimit,
-					GasPrice: dbGasPrice,
-					Hash:     dbHash,
-					Nonce:    dbNonce,
-					To:       dbTo,
-					Value:    dbValue,
-				}
-				savedTransactions = append(savedTransactions, savedTransaction)
-			}
-
-			Expect(len(savedTransactions)).To(Equal(1))
-			savedTransaction := savedTransactions[0]
-			Expect(savedTransaction.GasLimit).To(Equal(gasLimit))
-			Expect(savedTransaction.GasPrice).To(Equal(gasPrice))
-			Expect(savedTransaction.Hash).To(Equal(txRecord.Hash))
-			Expect(savedTransaction.Nonce).To(Equal(nonce))
-			Expect(savedTransaction.To).To(Equal(to))
-			Expect(savedTransaction.Value).To(Equal(value))
-		})
-
-		It("associates the transaction with the block", func() {
-			txRecord := core.Transaction{}
-			block := core.Block{
-				Transactions: []core.Transaction{txRecord},
 		}
 
 		observer := observers.BlockchainDBObserver{Db: db}
 		observer.NotifyBlockAdded(block)
 
-			blockRows, err := db.Query("SELECT id FROM blocks")
+		repository := repositories.NewPostgres(db)
-			Expect(err).To(BeNil())
+		savedBlock := repository.FindBlockByNumber(123)
-
+		Expect(savedBlock).NotTo(BeNil())
-			var actualBlockIds []int64
+		Expect(len(savedBlock.Transactions)).To(Equal(1))
-			for blockRows.Next() {
-				var actualBlockId int64
-				blockRows.Scan(&actualBlockId)
-				actualBlockIds = append(actualBlockIds, actualBlockId)
-			}
-
-			transactionRows, err := db.Query("SELECT block_id FROM transactions")
-			Expect(err).To(BeNil())
-
-			var transactionBlockIds []int64
-			for transactionRows.Next() {
-				var transactionBlockId int64
-				transactionRows.Scan(&transactionBlockId)
-				transactionBlockIds = append(transactionBlockIds, transactionBlockId)
-			}
-
-			Expect(len(actualBlockIds)).To(Equal(1))
-			Expect(len(transactionBlockIds)).To(Equal(1))
-			Expect(transactionBlockIds[0]).To(Equal(actualBlockIds[0]))
-		})
 	})
 
 })

repositories/postgres.go

@@ -0,0 +1,108 @@
+package repositories
+
+import (
+	"database/sql"
+
+	"github.com/8thlight/vulcanizedb/core"
+	"github.com/jmoiron/sqlx"
+	_ "github.com/lib/pq"
+)
+
+type Postgres struct {
+	Db *sqlx.DB
+}
+
+func NewPostgres(db *sqlx.DB) Postgres {
+	return Postgres{Db: db}
+}
+
+func (repository Postgres) FindBlockByNumber(blockNumber int64) *core.Block {
+	blockRows, _ := repository.Db.Query("SELECT id, block_number, block_gaslimit, block_gasused, block_time, block_difficulty, block_hash, block_nonce, block_parenthash, block_size, uncle_hash FROM blocks")
+	var savedBlocks []core.Block
+	for blockRows.Next() {
+		savedBlock := repository.loadBlock(blockRows)
+		savedBlocks = append(savedBlocks, savedBlock)
+	}
+	if len(savedBlocks) > 0 {
+		return &savedBlocks[0]
+	} else {
+		return nil
+	}
+}
+
+func (repository Postgres) BlockCount() int {
+	var count int
+	repository.Db.Get(&count, "SELECT COUNT(*) FROM blocks")
+	return count
+}
+
+func (repository Postgres) CreateBlock(block core.Block) {
+	insertedBlock := repository.Db.QueryRow(
+		"Insert INTO blocks "+
+			"(block_number, block_gaslimit, block_gasused, block_time, block_difficulty, block_hash, block_nonce, block_parenthash, block_size, uncle_hash) "+
+			"VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10) RETURNING id",
+		block.Number, block.GasLimit, block.GasUsed, block.Time, block.Difficulty, block.Hash, block.Nonce, block.ParentHash, block.Size, block.UncleHash)
+	var blockId int64
+	insertedBlock.Scan(&blockId)
+	repository.createTransactions(blockId, block.Transactions)
+}
+
+func (repository Postgres) createTransactions(blockId int64, transactions []core.Transaction) {
+	for _, transaction := range transactions {
+		repository.Db.MustExec("Insert INTO transactions "+
+			"(block_id, tx_hash, tx_nonce, tx_to, tx_gaslimit, tx_gasprice, tx_value) VALUES ($1, $2, $3, $4, $5, $6, $7)",
+			blockId, transaction.Hash, transaction.Nonce, transaction.To, transaction.GasLimit, transaction.GasPrice, transaction.Value)
+	}
+}
+
+func (repository Postgres) loadBlock(blockRows *sql.Rows) core.Block {
+	var blockId int64
+	var blockHash string
+	var blockNonce string
+	var blockNumber int64
+	var blockParentHash string
+	var blockSize int64
+	var blockTime float64
+	var difficulty int64
+	var gasLimit float64
+	var gasUsed float64
+	var uncleHash string
+	blockRows.Scan(&blockId, &blockNumber, &gasLimit, &gasUsed, &blockTime, &difficulty, &blockHash, &blockNonce, &blockParentHash, &blockSize, &uncleHash)
+	transactions := repository.loadTransactions(blockId)
+	return core.Block{
+		Difficulty:   difficulty,
+		GasLimit:     int64(gasLimit),
+		GasUsed:      int64(gasUsed),
+		Hash:         blockHash,
+		Nonce:        blockNonce,
+		Number:       blockNumber,
+		ParentHash:   blockParentHash,
+		Size:         blockSize,
+		Time:         int64(blockTime),
+		Transactions: transactions,
+		UncleHash:    uncleHash,
+	}
+}
+func (repository Postgres) loadTransactions(blockId int64) []core.Transaction {
+	transactionRows, _ := repository.Db.Query("SELECT tx_hash, tx_nonce, tx_to, tx_gaslimit, tx_gasprice, tx_value FROM transactions")
+	var transactions []core.Transaction
+	for transactionRows.Next() {
+		var hash string
+		var nonce uint64
+		var to string
+		var gasLimit int64
+		var gasPrice int64
+		var value int64
+		transactionRows.Scan(&hash, &nonce, &to, &gasLimit, &gasPrice, &value)
+		transaction := core.Transaction{
+			Hash:     hash,
+			Nonce:    nonce,
+			To:       to,
+			GasLimit: gasLimit,
+			GasPrice: gasPrice,
+			Value:    value,
+		}
+		transactions = append(transactions, transaction)
+	}
+	return transactions
+}

repositories/postgres_test.go

@@ -0,0 +1,159 @@
+package repositories_test
+
+import (
+	"github.com/8thlight/vulcanizedb/config"
+	"github.com/8thlight/vulcanizedb/core"
+	"github.com/8thlight/vulcanizedb/repositories"
+	"github.com/jmoiron/sqlx"
+	_ "github.com/lib/pq"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("The Postgres Repository", func() {
+
+	var db *sqlx.DB
+	var err error
+
+	BeforeEach(func() {
+		pgConfig := config.DbConnectionString(config.NewConfig("private").Database)
+		db, err = sqlx.Connect("postgres", pgConfig)
+		db.MustExec("DELETE FROM transactions")
+		db.MustExec("DELETE FROM blocks")
+	})
+
+	AfterEach(func() {
+		db.Close()
+	})
+
+	It("connects to the database", func() {
+		Expect(err).Should(BeNil())
+		Expect(db).ShouldNot(BeNil())
+	})
+
+	Describe("Saving blocks", func() {
+		It("starts with no blocks", func() {
+			count := repositories.NewPostgres(db).BlockCount()
+			Expect(count).Should(Equal(0))
+		})
+
+		It("increments the block count", func() {
+			block := core.Block{Number: 123}
+			repository := repositories.NewPostgres(db)
+
+			repository.CreateBlock(block)
+
+			Expect(repository.BlockCount()).To(Equal(1))
+		})
+
+		It("saves the attributes of the block", func() {
+			blockNumber := int64(123)
+			gasLimit := int64(1000000)
+			gasUsed := int64(10)
+			blockHash := "x123"
+			blockParentHash := "x456"
+			blockNonce := "0x881db2ca900682e9a9"
+			blockTime := int64(1508981640)
+			uncleHash := "x789"
+			blockSize := int64(1000)
+			difficulty := int64(10)
+			block := core.Block{
+				Difficulty: difficulty,
+				GasLimit:   gasLimit,
+				GasUsed:    gasUsed,
+				Hash:       blockHash,
+				Nonce:      blockNonce,
+				Number:     blockNumber,
+				ParentHash: blockParentHash,
+				Size:       blockSize,
+				Time:       blockTime,
+				UncleHash:  uncleHash,
+			}
+
+			repository := repositories.NewPostgres(db)
+
+			repository.CreateBlock(block)
+
+			savedBlock := repository.FindBlockByNumber(blockNumber)
+			Expect(savedBlock.Difficulty).To(Equal(difficulty))
+			Expect(savedBlock.GasLimit).To(Equal(gasLimit))
+			Expect(savedBlock.GasUsed).To(Equal(gasUsed))
+			Expect(savedBlock.Hash).To(Equal(blockHash))
+			Expect(savedBlock.Nonce).To(Equal(blockNonce))
+			Expect(savedBlock.Number).To(Equal(blockNumber))
+			Expect(savedBlock.ParentHash).To(Equal(blockParentHash))
+			Expect(savedBlock.Size).To(Equal(blockSize))
+			Expect(savedBlock.Time).To(Equal(blockTime))
+			Expect(savedBlock.UncleHash).To(Equal(uncleHash))
+		})
+
+		It("does not find a block when searching for a number that does not exist", func() {
+			repository := repositories.NewPostgres(db)
+
+			savedBlock := repository.FindBlockByNumber(111)
+
+			Expect(savedBlock).To(BeNil())
+		})
+
+		It("saves one transaction associated to the block", func() {
+			block := core.Block{
+				Number:       123,
+				Transactions: []core.Transaction{{}},
+			}
+			repository := repositories.NewPostgres(db)
+
+			repository.CreateBlock(block)
+
+			savedBlock := repository.FindBlockByNumber(123)
+			Expect(len(savedBlock.Transactions)).To(Equal(1))
+		})
+
+		It("saves two transactions associated to the block", func() {
+			block := core.Block{
+				Number:       123,
+				Transactions: []core.Transaction{{}, {}},
+			}
+			repository := repositories.NewPostgres(db)
+
+			repository.CreateBlock(block)
+
+			savedBlock := repository.FindBlockByNumber(123)
+			Expect(len(savedBlock.Transactions)).To(Equal(2))
+		})
+
+		It("saves the attributes associated to a transaction", func() {
+			gasLimit := int64(5000)
+			gasPrice := int64(3)
+			nonce := uint64(10000)
+			to := "1234567890"
+			value := int64(10)
+
+			transaction := core.Transaction{
+				Hash:     "x1234",
+				GasPrice: gasPrice,
+				GasLimit: gasLimit,
+				Nonce:    nonce,
+				To:       to,
+				Value:    value,
+			}
+			block := core.Block{
+				Number:       123,
+				Transactions: []core.Transaction{transaction},
+			}
+			repository := repositories.NewPostgres(db)
+
+			repository.CreateBlock(block)
+
+			savedBlock := repository.FindBlockByNumber(123)
+			Expect(len(savedBlock.Transactions)).To(Equal(1))
+			savedTransaction := savedBlock.Transactions[0]
+			Expect(savedTransaction.Hash).To(Equal(transaction.Hash))
+			Expect(savedTransaction.To).To(Equal(to))
+			Expect(savedTransaction.Nonce).To(Equal(nonce))
+			Expect(savedTransaction.GasLimit).To(Equal(gasLimit))
+			Expect(savedTransaction.GasPrice).To(Equal(gasPrice))
+			Expect(savedTransaction.Value).To(Equal(value))
+		})
+	})
+
+})

repositories/repositories_suite_test.go

@@ -0,0 +1,13 @@
+package repositories_test
+
+import (
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"testing"
+)
+
+func TestRepositories(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Repositories Suite")
+}