Update contract summary output to include transaction info

cmd/show_contract_summary/main.go

@@ -5,6 +5,8 @@ import (
 
 	"log"
 
+	"fmt"
+
 	"github.com/8thlight/vulcanizedb/cmd"
 	"github.com/8thlight/vulcanizedb/pkg/repositories"
 	"github.com/8thlight/vulcanizedb/pkg/watched_contracts"
@@ -21,5 +23,6 @@ func main() {
 	if err != nil {
 		log.Fatalln(err)
 	}
-	watched_contracts.PrintReport(contractSummary)
+	output := watched_contracts.GenerateConsoleOutput(contractSummary)
+	fmt.Println(output)
 }

pkg/repositories/postgres.go

@@ -200,7 +200,7 @@ func (repository Postgres) loadContract(contractRows *sql.Rows) []core.WatchedCo
 	for contractRows.Next() {
 		var savedContractHash string
 		contractRows.Scan(&savedContractHash)
-		transactionRows, _ := repository.Db.Query(`SELECT tx_hash, tx_nonce, tx_to, tx_from, tx_gaslimit, tx_gasprice, tx_value FROM transactions WHERE tx_to = $1`, savedContractHash)
+		transactionRows, _ := repository.Db.Query(`SELECT tx_hash, tx_nonce, tx_to, tx_from, tx_gaslimit, tx_gasprice, tx_value FROM transactions WHERE tx_to = $1 ORDER BY block_id desc`, savedContractHash)
 		transactions := repository.loadTransactions(transactionRows)
 		savedContract := core.WatchedContract{Hash: savedContractHash, Transactions: transactions}
 		savedContracts = append(savedContracts, savedContract)

pkg/watched_contracts/console_presenter.go

@@ -0,0 +1,34 @@
+package watched_contracts
+
+import (
+	"fmt"
+
+	"github.com/8thlight/vulcanizedb/pkg/core"
+)
+
+func GenerateConsoleOutput(summary *ContractSummary) string {
+	return fmt.Sprintf(template(),
+		summary.ContractHash,
+		summary.NumberOfTransactions,
+		transactionToString(summary.LastTransaction),
+	)
+}
+
+func template() string {
+	return `********************Contract Summary***********************
+	                  HASH: %v
+	NUMBER OF TRANSACTIONS: %d
+	      LAST TRANSACTION:
+	                        %s
+	`
+}
+
+func transactionToString(transaction *core.Transaction) string {
+	if transaction == nil {
+		return "NONE"
+	} else {
+		return fmt.Sprintf(`Hash: %s
+                        To: %s
+                        From: %s`, transaction.Hash, transaction.To, transaction.From)
+	}
+}

pkg/watched_contracts/reporter.go

@@ -1,10 +0,0 @@
-package watched_contracts
-
-import "fmt"
-
-func PrintReport(summary *ContractSummary) {
-	fmt.Printf(`********************Contract Summary***********************
-
-HASH: %v
-`, summary.ContractHash)
-}

pkg/watched_contracts/summary.go

@@ -10,6 +10,8 @@ import (
 
 type ContractSummary struct {
 	ContractHash         string
+	NumberOfTransactions int
+	LastTransaction      *core.Transaction
 }
 
 var NewContractNotWatchedErr = func(contractHash string) error {
@@ -26,5 +28,17 @@ func NewSummary(repository repositories.Repository, contractHash string) (*Contr
 }
 
 func newContractSummary(contract core.WatchedContract) *ContractSummary {
-	return &ContractSummary{ContractHash: contract.Hash}
+	return &ContractSummary{
+		ContractHash:         contract.Hash,
+		NumberOfTransactions: len(contract.Transactions),
+		LastTransaction:      lastTransaction(contract),
+	}
+}
+
+func lastTransaction(contract core.WatchedContract) *core.Transaction {
+	if len(contract.Transactions) > 0 {
+		return &contract.Transactions[0]
+	} else {
+		return nil
+	}
 }

pkg/watched_contracts/summary_test.go

@@ -8,7 +8,7 @@ import (
 	. "github.com/onsi/gomega"
 )
 
-var _ = Describe("The watched contract summary", func() {
+var _ bool = Describe("The watched contract summary", func() {
 
 	Context("when the given contract is not being watched", func() {
 		It("returns an error", func() {
@@ -42,6 +42,40 @@ var _ = Describe("The watched contract summary", func() {
 
 			Expect(contractSummary.ContractHash).To(Equal("0x123"))
 		})
+
+		It("sets the number of transactions", func() {
+			repository := repositories.NewInMemory()
+			watchedContract := core.WatchedContract{Hash: "0x123"}
+			repository.CreateWatchedContract(watchedContract)
+			block := core.Block{
+				Transactions: []core.Transaction{
+					{To: "0x123"},
+					{To: "0x123"},
+				},
+			}
+			repository.CreateBlock(block)
+
+			contractSummary, _ := watched_contracts.NewSummary(repository, "0x123")
+
+			Expect(contractSummary.NumberOfTransactions).To(Equal(2))
+		})
+
+		It("sets the last transaction", func() {
+			repository := repositories.NewInMemory()
+			watchedContract := core.WatchedContract{Hash: "0x123"}
+			repository.CreateWatchedContract(watchedContract)
+			block := core.Block{
+				Transactions: []core.Transaction{
+					{Hash: "TRANSACTION2", To: "0x123"},
+					{Hash: "TRANSACTION1", To: "0x123"},
+				},
+			}
+			repository.CreateBlock(block)
+
+			contractSummary, _ := watched_contracts.NewSummary(repository, "0x123")
+
+			Expect(contractSummary.LastTransaction.Hash).To(Equal("TRANSACTION2"))
+		})
 	})
 
 })