Merge pull request #78 from 8thlight/add-contract-state-to-contract-summary

Add contract state to contract summary

.gitignore

@@ -2,4 +2,5 @@
 Gododir/godobin-*
 test_data_dir/
 vendor/
+contracts/*
 environments/*.toml

Gopkg.lock

@@ -13,6 +13,12 @@
   packages = ["."]
   revision = "4748e29d5718c2df4028a6543edf86fd8cc0f881"
 
+[[projects]]
+  branch = "master"
+  name = "github.com/aristanetworks/goarista"
+  packages = ["monotime"]
+  revision = "54fadd0c513d502544edf098480238dc9da50f9e"
+
 [[projects]]
   branch = "master"
   name = "github.com/btcsuite/btcd"
@@ -21,7 +27,7 @@
 
 [[projects]]
   name = "github.com/ethereum/go-ethereum"
-  packages = [".","common","common/hexutil","common/math","core/types","crypto","crypto/secp256k1","crypto/sha3","ethclient","log","params","rlp","rpc","trie"]
+  packages = [".","accounts","accounts/abi","accounts/abi/bind","accounts/keystore","common","common/hexutil","common/math","common/mclock","core/types","crypto","crypto/randentropy","crypto/secp256k1","crypto/sha3","ethclient","event","log","params","rlp","rpc","trie"]
   revision = "1db4ecdc0b9e828ff65777fb466fc7c1d04e0de9"
   version = "v1.7.2"
 
@@ -103,12 +109,24 @@
   revision = "c893efa28eb45626cdaa76c9f653b62488858837"
   version = "v1.2.0"
 
+[[projects]]
+  name = "github.com/pborman/uuid"
+  packages = ["."]
+  revision = "e790cca94e6cc75c7064b1332e63811d4aae1a53"
+  version = "v1.1"
+
 [[projects]]
   branch = "master"
   name = "github.com/rcrowley/go-metrics"
   packages = ["."]
   revision = "1f30fe9094a513ce4c700b9a54458bbb0c96996c"
 
+[[projects]]
+  branch = "master"
+  name = "github.com/rjeczalik/notify"
+  packages = ["."]
+  revision = "767eb674ef14b09119b2fff3601e64558d530c47"
+
 [[projects]]
   name = "github.com/rs/cors"
   packages = ["."]
@@ -118,7 +136,7 @@
 [[projects]]
   branch = "master"
   name = "golang.org/x/crypto"
-  packages = ["ssh/terminal"]
+  packages = ["pbkdf2","scrypt","ssh/terminal"]
   revision = "bd6f299fb381e4c3393d1c4b1f0b94f5e77650c8"
 
 [[projects]]
@@ -139,6 +157,12 @@
   packages = ["encoding","encoding/charmap","encoding/htmlindex","encoding/internal","encoding/internal/identifier","encoding/japanese","encoding/korean","encoding/simplifiedchinese","encoding/traditionalchinese","encoding/unicode","internal/gen","internal/tag","internal/utf8internal","language","runes","transform","unicode/cldr"]
   revision = "c01e4764d870b77f8abe5096ee19ad20d80e8075"
 
+[[projects]]
+  branch = "master"
+  name = "golang.org/x/tools"
+  packages = ["go/ast/astutil","imports"]
+  revision = "6d70fb2e85323e81c89374331d3d2b93304faa36"
+
 [[projects]]
   name = "gopkg.in/fatih/set.v0"
   packages = ["."]
@@ -172,6 +196,6 @@
 [solve-meta]
   analyzer-name = "dep"
   analyzer-version = 1
-  inputs-digest = "f9569275c3b9863e5209029135f13d3d9df9a697b49e75b5cbd37942b23e4f3b"
+  inputs-digest = "d2aa2bdc1442319cde6fe38b39e0ff8e25b1a0b0c120a7e2fab8065324c98693"
   solver-name = "gps-cdcl"
   solver-version = 1

cmd/run/main.go

@@ -17,9 +17,9 @@ func main() {
 	environment := flag.String("environment", "", "Environment name")
 	flag.Parse()
 	config := cmd.LoadConfig(*environment)
-	fmt.Println("Client Path ", config.Client.IPCPath)
 
 	repository := repositories.NewPostgres(config.Database)
+	fmt.Printf("Creating Geth Blockchain to: %s\n", config.Client.IPCPath)
 	listener := blockchain_listener.NewBlockchainListener(
 		geth.NewGethBlockchain(config.Client.IPCPath),
 		[]core.BlockchainObserver{

cmd/show_contract_summary/main.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 
 	"github.com/8thlight/vulcanizedb/cmd"
+	"github.com/8thlight/vulcanizedb/pkg/geth"
 	"github.com/8thlight/vulcanizedb/pkg/repositories"
 	"github.com/8thlight/vulcanizedb/pkg/watched_contracts"
 )
@@ -18,8 +19,9 @@ func main() {
 	flag.Parse()
 	config := cmd.LoadConfig(*environment)
 
+	blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
 	repository := repositories.NewPostgres(config.Database)
-	contractSummary, err := watched_contracts.NewSummary(repository, *contractHash)
+	contractSummary, err := watched_contracts.NewSummary(blockchain, repository, *contractHash)
 	if err != nil {
 		log.Fatalln(err)
 	}

db/schema.sql

@@ -2,7 +2,7 @@
 -- PostgreSQL database dump
 --
 
--- Dumped from database version 10.0
+-- Dumped from database version 10.1
 -- Dumped by pg_dump version 10.1
 
 SET statement_timeout = 0;

pkg/core/blockchain.go

@@ -5,4 +5,6 @@ type Blockchain interface {
 	SubscribeToBlocks(blocks chan Block)
 	StartListening()
 	StopListening()
+	GetContractAttributes(contractHash string) (ContractAttributes, error)
+	GetContractStateAttribute(contractHash string, attributeName string) (*string, error)
 }

pkg/core/watched_contract.go

@@ -4,3 +4,21 @@ type WatchedContract struct {
 	Hash         string
 	Transactions []Transaction
 }
+
+type ContractAttribute struct {
+	Name string
+	Type string
+}
+
+type ContractAttributes []ContractAttribute
+
+func (attributes ContractAttributes) Len() int {
+	return len(attributes)
+}
+func (attributes ContractAttributes) Swap(i, j int) {
+	attributes[i], attributes[j] = attributes[j], attributes[i]
+}
+
+func (attributes ContractAttributes) Less(i, j int) bool {
+	return attributes[i].Name < attributes[j].Name
+}

pkg/fakes/blockchain.go

@@ -1,15 +1,40 @@
 package fakes
 
-import "github.com/8thlight/vulcanizedb/pkg/core"
+import (
+	"github.com/8thlight/vulcanizedb/pkg/core"
+	"sort"
+)
 
 type Blockchain struct {
-	blocks        map[int64]core.Block
-	blocksChannel chan core.Block
-	WasToldToStop bool
+	blocks             map[int64]core.Block
+	contractAttributes map[string]map[string]string
+	blocksChannel      chan core.Block
+	WasToldToStop      bool
+}
+
+func (blockchain *Blockchain) GetContractAttributes(contractHash string) (core.ContractAttributes, error) {
+	var contractAttributes core.ContractAttributes
+	attributes, ok := blockchain.contractAttributes[contractHash]
+	if ok {
+		for key, _ := range attributes {
+			contractAttributes = append(contractAttributes, core.ContractAttribute{Name: key, Type: "string"})
+		}
+	}
+	sort.Sort(contractAttributes)
+	return contractAttributes, nil
+}
+
+func (blockchain *Blockchain) GetContractStateAttribute(contractHash string, attributeName string) (*string, error) {
+	result := new(string)
+	*result = blockchain.contractAttributes[contractHash][attributeName]
+	return result, nil
 }
 
 func NewBlockchain() *Blockchain {
-	return &Blockchain{blocks: make(map[int64]core.Block)}
+	return &Blockchain{
+		blocks:             make(map[int64]core.Block),
+		contractAttributes: make(map[string]map[string]string),
+	}
 }
 
 func NewBlockchainWithBlocks(blocks []core.Block) *Blockchain {
@@ -40,3 +65,11 @@ func (*Blockchain) StartListening() {}
 func (blockchain *Blockchain) StopListening() {
 	blockchain.WasToldToStop = true
 }
+
+func (blockchain *Blockchain) SetContractStateAttribute(contractHash string, attributeName string, attributeValue string) {
+	contractStateAttributes := blockchain.contractAttributes[contractHash]
+	if contractStateAttributes == nil {
+		blockchain.contractAttributes[contractHash] = make(map[string]string)
+	}
+	blockchain.contractAttributes[contractHash][attributeName] = attributeValue
+}

pkg/geth/abi.go

@@ -0,0 +1,27 @@
+package geth
+
+import (
+	"errors"
+	"io/ioutil"
+	"strings"
+
+	"github.com/ethereum/go-ethereum/accounts/abi"
+)
+
+var (
+	ErrInvalidAbiFile = errors.New("invalid abi")
+	ErrMissingAbiFile = errors.New("missing abi")
+)
+
+func ParseAbiFile(abiFilePath string) (abi.ABI, error) {
+	filesBytes, err := ioutil.ReadFile(abiFilePath)
+	if err != nil {
+		return abi.ABI{}, ErrMissingAbiFile
+	}
+	abiString := string(filesBytes)
+	parsedAbi, err := abi.JSON(strings.NewReader(abiString))
+	if err != nil {
+		return abi.ABI{}, ErrInvalidAbiFile
+	}
+	return parsedAbi, nil
+}

pkg/geth/abi_test.go

@@ -0,0 +1,42 @@
+package geth_test
+
+import (
+	"path/filepath"
+
+	cfg "github.com/8thlight/vulcanizedb/pkg/config"
+	"github.com/8thlight/vulcanizedb/pkg/geth"
+	"github.com/ethereum/go-ethereum/accounts/abi"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Reading ABI files", func() {
+
+	It("loads a valid ABI file", func() {
+		path := filepath.Join(cfg.ProjectRoot(), "pkg", "geth", "testing", "valid_abi.json")
+
+		contractAbi, err := geth.ParseAbiFile(path)
+
+		Expect(contractAbi).NotTo(BeNil())
+		Expect(err).To(BeNil())
+	})
+
+	It("returns an error when the file does not exist", func() {
+		path := filepath.Join(cfg.ProjectRoot(), "pkg", "geth", "testing", "missing_abi.json")
+
+		contractAbi, err := geth.ParseAbiFile(path)
+
+		Expect(contractAbi).To(Equal(abi.ABI{}))
+		Expect(err).To(Equal(geth.ErrMissingAbiFile))
+	})
+
+	It("returns an error when the file has invalid contents", func() {
+		path := filepath.Join(cfg.ProjectRoot(), "pkg", "geth", "testing", "invalid_abi.json")
+
+		contractAbi, err := geth.ParseAbiFile(path)
+
+		Expect(contractAbi).To(Equal(abi.ABI{}))
+		Expect(err).To(Equal(geth.ErrInvalidAbiFile))
+	})
+
+})

pkg/geth/contract.go

@@ -0,0 +1,54 @@
+package geth
+
+import (
+	"errors"
+	"fmt"
+	"path/filepath"
+
+	"sort"
+
+	"github.com/8thlight/vulcanizedb/pkg/config"
+	"github.com/8thlight/vulcanizedb/pkg/core"
+	"github.com/ethereum/go-ethereum/accounts/abi/bind"
+	"github.com/ethereum/go-ethereum/common"
+)
+
+var (
+	ErrInvalidStateAttribute = errors.New("invalid state attribute")
+)
+
+func (blockchain *GethBlockchain) GetContractAttributes(contractHash string) (core.ContractAttributes, error) {
+	abiFilePath := filepath.Join(config.ProjectRoot(), "contracts", "public", fmt.Sprintf("%s.json", contractHash))
+	parsed, _ := ParseAbiFile(abiFilePath)
+	var contractAttributes core.ContractAttributes
+	for _, abiElement := range parsed.Methods {
+		if (len(abiElement.Outputs) > 0) && (len(abiElement.Inputs) == 0) && abiElement.Const && abiElement.Outputs[0].Type.String() == "string" {
+			attributeType := abiElement.Outputs[0].Type.String()
+			contractAttributes = append(contractAttributes, core.ContractAttribute{abiElement.Name, attributeType})
+		}
+	}
+	sort.Sort(contractAttributes)
+	return contractAttributes, nil
+}
+
+func (blockchain *GethBlockchain) GetContractStateAttribute(contractHash string, attributeName string) (*string, error) {
+	boundContract, err := bindContract(common.HexToAddress(contractHash), blockchain.client, blockchain.client)
+	if err != nil {
+		return nil, err
+	}
+	result := new(string)
+	err = boundContract.Call(&bind.CallOpts{}, result, attributeName)
+	if err != nil {
+		return nil, ErrInvalidStateAttribute
+	}
+	return result, nil
+}
+
+func bindContract(address common.Address, caller bind.ContractCaller, transactor bind.ContractTransactor) (*bind.BoundContract, error) {
+	abiFilePath := filepath.Join(config.ProjectRoot(), "contracts", "public", fmt.Sprintf("%s.json", address.Hex()))
+	parsed, err := ParseAbiFile(abiFilePath)
+	if err != nil {
+		return nil, err
+	}
+	return bind.NewBoundContract(address, parsed, caller, transactor), nil
+}

pkg/geth/contract_test.go

@@ -0,0 +1,100 @@
+package geth_test
+
+//import (
+//	cfg "github.com/8thlight/vulcanizedb/pkg/config"
+//	"github.com/8thlight/vulcanizedb/pkg/geth"
+//	"github.com/8thlight/vulcanizedb/pkg/geth/testing"
+//	. "github.com/onsi/ginkgo"
+//	. "github.com/onsi/gomega"
+//)
+//
+//var _ = Describe("Reading contracts", func() {
+//
+//	Describe("Reading the list of attributes", func() {
+//		It("returns a string attribute for a real contract", func() {
+//			config, _ := cfg.NewConfig("public")
+//			blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
+//			contractHash := "0xd26114cd6EE289AccF82350c8d8487fedB8A0C07"
+//
+//			attributes, err := blockchain.GetContractAttributes(contractHash)
+//
+//			Expect(err).To(BeNil())
+//			Expect(len(attributes)).NotTo(Equal(0))
+//			symbolAttribute := *testing.FindAttribute(attributes, "symbol")
+//			Expect(symbolAttribute.Name).To(Equal("symbol"))
+//			Expect(symbolAttribute.Type).To(Equal("string"))
+//		})
+//
+//		It("does not return an attribute that takes an input", func() {
+//			config, _ := cfg.NewConfig("public")
+//			blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
+//			contractHash := "0xd26114cd6EE289AccF82350c8d8487fedB8A0C07"
+//
+//			attributes, err := blockchain.GetContractAttributes(contractHash)
+//
+//			Expect(err).To(BeNil())
+//			attribute := testing.FindAttribute(attributes, "balanceOf")
+//			Expect(attribute).To(BeNil())
+//		})
+//
+//		It("does not return an attribute that is not constant", func() {
+//			config, _ := cfg.NewConfig("public")
+//			blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
+//			contractHash := "0xd26114cd6EE289AccF82350c8d8487fedB8A0C07"
+//
+//			attributes, err := blockchain.GetContractAttributes(contractHash)
+//
+//			Expect(err).To(BeNil())
+//			attribute := testing.FindAttribute(attributes, "unpause")
+//			Expect(attribute).To(BeNil())
+//		})
+//
+//		It("temporarily filters out non-string attributes", func() {
+//			config, _ := cfg.NewConfig("public")
+//			blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
+//			contractHash := "0xd26114cd6EE289AccF82350c8d8487fedB8A0C07"
+//
+//			attributes, err := blockchain.GetContractAttributes(contractHash)
+//
+//			Expect(err).To(BeNil())
+//			attribute := testing.FindAttribute(attributes, "decimals")
+//			Expect(attribute).To(BeNil())
+//		})
+//	})
+//
+//	Describe("Getting a contract attribute", func() {
+//		It("returns the correct attribute for a real contract", func() {
+//			config, _ := cfg.NewConfig("public")
+//			blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
+//			contractHash := "0xd26114cd6EE289AccF82350c8d8487fedB8A0C07"
+//
+//			name, err := blockchain.GetContractStateAttribute(contractHash, "name")
+//
+//			Expect(*name).To(Equal("OMGToken"))
+//			Expect(err).To(BeNil())
+//		})
+//
+//		It("returns an error when there is no ABI for the given contract", func() {
+//			config, _ := cfg.NewConfig("public")
+//			blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
+//			contractHash := "MISSINGHASH"
+//
+//			name, err := blockchain.GetContractStateAttribute(contractHash, "name")
+//
+//			Expect(name).To(BeNil())
+//			Expect(err).To(Equal(geth.ErrMissingAbiFile))
+//		})
+//
+//		It("returns an error when asking for an attribute that does not exist", func() {
+//			config, _ := cfg.NewConfig("public")
+//			blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
+//			contractHash := "0xd26114cd6EE289AccF82350c8d8487fedB8A0C07"
+//
+//			name, err := blockchain.GetContractStateAttribute(contractHash, "missing_attribute")
+//
+//			Expect(err).To(Equal(geth.ErrInvalidStateAttribute))
+//			Expect(name).To(BeNil())
+//		})
+//	})
+//
+//})

pkg/geth/geth_blockchain.go

@@ -25,7 +25,6 @@ func (blockchain *GethBlockchain) GetBlockByNumber(blockNumber int64) core.Block
 }
 
 func NewGethBlockchain(ipcPath string) *GethBlockchain {
-	fmt.Printf("Creating Geth Blockchain to: %s\n", ipcPath)
 	blockchain := GethBlockchain{}
 	client, _ := ethclient.Dial(ipcPath)
 	blockchain.client = client

pkg/geth/testing/contract_attributes.go

@@ -0,0 +1,14 @@
+package testing
+
+import (
+	"github.com/8thlight/vulcanizedb/pkg/core"
+)
+
+func FindAttribute(contractAttributes core.ContractAttributes, attributeName string) *core.ContractAttribute {
+	for _, contractAttribute := range contractAttributes {
+		if contractAttribute.Name == attributeName {
+			return &contractAttribute
+		}
+	}
+	return nil
+}

pkg/geth/testing/invalid_abi.json

@@ -0,0 +1 @@
+bad json

pkg/geth/testing/valid_abi.json

@@ -0,0 +1 @@
+[{"constant":true,"inputs":[],"name":"mintingFinished","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"name","outputs":[{"name":"","type":"string"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_spender","type":"address"},{"name":"_value","type":"uint256"}],"name":"approve","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"totalSupply","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_from","type":"address"},{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transferFrom","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"decimals","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"unpause","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_to","type":"address"},{"name":"_amount","type":"uint256"}],"name":"mint","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"paused","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_owner","type":"address"}],"name":"balanceOf","outputs":[{"name":"balance","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"finishMinting","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"pause","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"owner","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"symbol","outputs":[{"name":"","type":"string"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transfer","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_to","type":"address"},{"name":"_amount","type":"uint256"},{"name":"_releaseTime","type":"uint256"}],"name":"mintTimelocked","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_owner","type":"address"},{"name":"_spender","type":"address"}],"name":"allowance","outputs":[{"name":"remaining","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"payable":false,"type":"function"},{"anonymous":false,"inputs":[{"indexed":true,"name":"to","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Mint","type":"event"},{"anonymous":false,"inputs":[],"name":"MintFinished","type":"event"},{"anonymous":false,"inputs":[],"name":"Pause","type":"event"},{"anonymous":false,"inputs":[],"name":"Unpause","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"owner","type":"address"},{"indexed":true,"name":"spender","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"from","type":"address"},{"indexed":true,"name":"to","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Transfer","type":"event"}]

pkg/watched_contracts/console_presenter.go

@@ -11,15 +11,18 @@ func GenerateConsoleOutput(summary *ContractSummary) string {
 		summary.ContractHash,
 		summary.NumberOfTransactions,
 		transactionToString(summary.LastTransaction),
+		attributesString(summary),
 	)
 }
 
 func template() string {
 	return `********************Contract Summary***********************
-	                  HASH: %v
-	NUMBER OF TRANSACTIONS: %d
-	      LAST TRANSACTION:
-	                        %s
+                      HASH: %v
+    NUMBER OF TRANSACTIONS: %d
+          LAST TRANSACTION:
+                            %s
+                ATTRIBUTES:
+                            %s
 	`
 }
 
@@ -28,7 +31,20 @@ func transactionToString(transaction *core.Transaction) string {
 		return "NONE"
 	} else {
 		return fmt.Sprintf(`Hash: %s
-                        To: %s
-                        From: %s`, transaction.Hash, transaction.To, transaction.From)
+                              To: %s
+                            From: %s`, transaction.Hash, transaction.To, transaction.From)
 	}
 }
+
+func attributesString(summary *ContractSummary) string {
+	var formattedAttributes string
+	for _, attribute := range summary.Attributes {
+		formattedAttributes += formatAttribute(attribute.Name, summary) + "\n" + "                            "
+	}
+	return formattedAttributes
+}
+
+func formatAttribute(attributeName string, summary *ContractSummary) string {
+	formattedAttribute := fmt.Sprintf("%s: %s", attributeName, summary.GetStateAttribute(attributeName))
+	return formattedAttribute
+}

pkg/watched_contracts/summary.go

@@ -12,26 +12,36 @@ type ContractSummary struct {
 	ContractHash         string
 	NumberOfTransactions int
 	LastTransaction      *core.Transaction
+	blockChain           core.Blockchain
+	Attributes           core.ContractAttributes
 }
 
 var NewContractNotWatchedErr = func(contractHash string) error {
 	return errors.New(fmt.Sprintf("Contract %v not being watched", contractHash))
 }
 
-func NewSummary(repository repositories.Repository, contractHash string) (*ContractSummary, error) {
-	contract := repository.FindWatchedContract(contractHash)
-	if contract != nil {
-		return newContractSummary(*contract), nil
+func NewSummary(blockchain core.Blockchain, repository repositories.Repository, contractHash string) (*ContractSummary, error) {
+	watchedContract := repository.FindWatchedContract(contractHash)
+	if watchedContract != nil {
+		return newContractSummary(blockchain, *watchedContract), nil
 	} else {
 		return nil, NewContractNotWatchedErr(contractHash)
 	}
 }
 
-func newContractSummary(contract core.WatchedContract) *ContractSummary {
+func (contractSummary ContractSummary) GetStateAttribute(attributeName string) string {
+	result, _ := contractSummary.blockChain.GetContractStateAttribute(contractSummary.ContractHash, attributeName)
+	return *result
+}
+
+func newContractSummary(blockchain core.Blockchain, watchedContract core.WatchedContract) *ContractSummary {
+	attributes, _ := blockchain.GetContractAttributes(watchedContract.Hash)
 	return &ContractSummary{
-		ContractHash:         contract.Hash,
-		NumberOfTransactions: len(contract.Transactions),
-		LastTransaction:      lastTransaction(contract),
+		blockChain:           blockchain,
+		ContractHash:         watchedContract.Hash,
+		NumberOfTransactions: len(watchedContract.Transactions),
+		LastTransaction:      lastTransaction(watchedContract),
+		Attributes:           attributes,
 	}
 }
 

pkg/watched_contracts/summary_test.go

@@ -2,6 +2,7 @@ package watched_contracts_test
 
 import (
 	"github.com/8thlight/vulcanizedb/pkg/core"
+	"github.com/8thlight/vulcanizedb/pkg/fakes"
 	"github.com/8thlight/vulcanizedb/pkg/repositories"
 	"github.com/8thlight/vulcanizedb/pkg/watched_contracts"
 	. "github.com/onsi/ginkgo"
@@ -13,8 +14,9 @@ var _ bool = Describe("The watched contract summary", func() {
 	Context("when the given contract is not being watched", func() {
 		It("returns an error", func() {
 			repository := repositories.NewInMemory()
+			blockchain := fakes.NewBlockchain()
 
-			contractSummary, err := watched_contracts.NewSummary(repository, "123")
+			contractSummary, err := watched_contracts.NewSummary(blockchain, repository, "123")
 
 			Expect(contractSummary).To(BeNil())
 			Expect(err).NotTo(BeNil())
@@ -26,8 +28,9 @@ var _ bool = Describe("The watched contract summary", func() {
 			repository := repositories.NewInMemory()
 			watchedContract := core.WatchedContract{Hash: "0x123"}
 			repository.CreateWatchedContract(watchedContract)
+			blockchain := fakes.NewBlockchain()
 
-			contractSummary, err := watched_contracts.NewSummary(repository, "0x123")
+			contractSummary, err := watched_contracts.NewSummary(blockchain, repository, "0x123")
 
 			Expect(contractSummary).NotTo(BeNil())
 			Expect(err).To(BeNil())
@@ -37,8 +40,9 @@ var _ bool = Describe("The watched contract summary", func() {
 			repository := repositories.NewInMemory()
 			watchedContract := core.WatchedContract{Hash: "0x123"}
 			repository.CreateWatchedContract(watchedContract)
+			blockchain := fakes.NewBlockchain()
 
-			contractSummary, _ := watched_contracts.NewSummary(repository, "0x123")
+			contractSummary, _ := watched_contracts.NewSummary(blockchain, repository, "0x123")
 
 			Expect(contractSummary.ContractHash).To(Equal("0x123"))
 		})
@@ -54,8 +58,9 @@ var _ bool = Describe("The watched contract summary", func() {
 				},
 			}
 			repository.CreateBlock(block)
+			blockchain := fakes.NewBlockchain()
 
-			contractSummary, _ := watched_contracts.NewSummary(repository, "0x123")
+			contractSummary, _ := watched_contracts.NewSummary(blockchain, repository, "0x123")
 
 			Expect(contractSummary.NumberOfTransactions).To(Equal(2))
 		})
@@ -71,11 +76,42 @@ var _ bool = Describe("The watched contract summary", func() {
 				},
 			}
 			repository.CreateBlock(block)
+			blockchain := fakes.NewBlockchain()
 
-			contractSummary, _ := watched_contracts.NewSummary(repository, "0x123")
+			contractSummary, _ := watched_contracts.NewSummary(blockchain, repository, "0x123")
 
 			Expect(contractSummary.LastTransaction.Hash).To(Equal("TRANSACTION2"))
 		})
+
+		It("gets contract state attribute for the contract from the blockchain", func() {
+			repository := repositories.NewInMemory()
+			watchedContract := core.WatchedContract{Hash: "0x123"}
+			repository.CreateWatchedContract(watchedContract)
+			blockchain := fakes.NewBlockchain()
+			blockchain.SetContractStateAttribute("0x123", "foo", "bar")
+
+			contractSummary, _ := watched_contracts.NewSummary(blockchain, repository, "0x123")
+
+			Expect(contractSummary.GetStateAttribute("foo")).To(Equal("bar"))
+		})
+
+		It("gets attributes for the contract from the blockchain", func() {
+			repository := repositories.NewInMemory()
+			watchedContract := core.WatchedContract{Hash: "0x123"}
+			repository.CreateWatchedContract(watchedContract)
+			blockchain := fakes.NewBlockchain()
+			blockchain.SetContractStateAttribute("0x123", "foo", "bar")
+			blockchain.SetContractStateAttribute("0x123", "baz", "bar")
+
+			contractSummary, _ := watched_contracts.NewSummary(blockchain, repository, "0x123")
+
+			Expect(contractSummary.Attributes).To(Equal(
+				core.ContractAttributes{
+					{Name: "baz", Type: "string"},
+					{Name: "foo", Type: "string"},
+				},
+			))
+		})
 	})
 
 })