Add integration test

* Update Travis to run integration tests

.gitignore

@@ -1 +1,2 @@
 .idea
+test_data_dir/

.private_blockchain_password

@@ -0,0 +1 @@
+1234

.travis.yml

@@ -1,3 +1,5 @@
 language: go
 go:
   - 1.9
+script:
+  - go test -v ./core/...

README.md

@@ -10,4 +10,15 @@ By default, `go get` does not work for private GitHub repos. This will fix that.
 
 ## Running the Tests
 
-`go test ./...`
+### Integration Test
+
+In order to run the integration tests, you will need to run them against a real blockchain. Here are steps to create a local, private blockchain.
+
+1. Run `./scripts/setup` to create a private blockchain with a new account.
+    * This will result in a warning.
+2. Run `./scripts/start_private_blockchain` as a separate process.
+3. `go test ./...`
+
+### Unit Tests
+
+`go test ./core`

core/fake_blockchain_test.go

@@ -46,8 +46,8 @@ var _ = Describe("The fake blockchain", func() {
 
 		blockchain.AddBlock(core.Block{Number: big.NewInt(123)})
 
-		Expect(blockchainObserver.LastAddedBlock.Number).ShouldNot(BeNil())
+		Expect(blockchainObserver.LastAddedBlock().Number).ShouldNot(BeNil())
-		Expect(blockchainObserver.LastAddedBlock.Number).Should(Equal(big.NewInt(123)))
+		Expect(blockchainObserver.LastAddedBlock().Number).Should(Equal(big.NewInt(123)))
 	})
 
 })

core/geth_blockchain.go

@@ -2,6 +2,7 @@ package core
 
 import (
 	"fmt"
+	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/ethclient"
 	"golang.org/x/net/context"
@@ -9,8 +10,9 @@ import (
 )
 
 type GethBlockchain struct {
-	client    *ethclient.Client
+	client       *ethclient.Client
-	observers []BlockchainObserver
+	observers    []BlockchainObserver
+	subscription ethereum.Subscription
 }
 
 func NewGethBlockchain(ipcPath string) *GethBlockchain {
@@ -21,12 +23,14 @@ func NewGethBlockchain(ipcPath string) *GethBlockchain {
 	blockchain.client = client
 	return &blockchain
 }
+
 func (blockchain GethBlockchain) notifyObservers(getBlock *types.Block) {
 	block := convertBlock(getBlock)
 	for _, observer := range blockchain.observers {
 		observer.NotifyBlockAdded(block)
 	}
 }
+
 func convertBlock(gethBlock *types.Block) Block {
 	return Block{
 		Number:               gethBlock.Number(),
@@ -42,7 +46,8 @@ func (blockchain *GethBlockchain) RegisterObserver(observer BlockchainObserver)
 func (blockchain *GethBlockchain) SubscribeToEvents() {
 	headers := make(chan *types.Header, 10)
 	myContext := context.Background()
-	blockchain.client.SubscribeNewHead(myContext, headers)
+	sub, _ := blockchain.client.SubscribeNewHead(myContext, headers)
+	blockchain.subscription = sub
 	for header := range headers {
 		gethBlock, _ := blockchain.client.BlockByNumber(myContext, header.Number)
 		blockchain.notifyObservers(gethBlock)

fakes/blockchain.go

@@ -18,5 +18,4 @@ func (blockchain *Blockchain) AddBlock(block core.Block) {
 	}
 }
 
-func (_ *Blockchain) SubscribeToEvents() {
+func (_ *Blockchain) SubscribeToEvents() {}
-}

fakes/blockchain_observer.go

@@ -6,7 +6,7 @@ import (
 
 type BlockchainObserver struct {
 	wasToldBlockAdded bool
-	LastAddedBlock    core.Block
+	blocks            []core.Block
 }
 
 func (blockchainObserver *BlockchainObserver) WasToldBlockAdded() bool {
@@ -14,6 +14,10 @@ func (blockchainObserver *BlockchainObserver) WasToldBlockAdded() bool {
 }
 
 func (blockchainObserver *BlockchainObserver) NotifyBlockAdded(block core.Block) {
-	blockchainObserver.LastAddedBlock = block
+	blockchainObserver.blocks = append(blockchainObserver.blocks, block)
 	blockchainObserver.wasToldBlockAdded = true
 }
+
+func (observer *BlockchainObserver) LastAddedBlock() core.Block {
+	return observer.blocks[len(observer.blocks)-1]
+}

integration_test/geth_blockchain_test.go

@@ -0,0 +1,51 @@
+package integration_test
+
+import (
+	"fmt"
+	"github.com/8thlight/vulcanizedb/core"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"math/big"
+	"path"
+	"path/filepath"
+	"runtime"
+)
+
+var (
+	_, filename, _, _ = runtime.Caller(0)
+	basepath          = filepath.Dir(filename)
+)
+
+func RunTimePath() string {
+	return path.Join(path.Dir(filename), "../")
+}
+
+type ObserverWithChannel struct {
+	blocks chan core.Block
+}
+
+func (observer *ObserverWithChannel) NotifyBlockAdded(block core.Block) {
+	fmt.Println("Block: ", block.Number)
+	observer.blocks <- block
+}
+
+var _ = Describe("Reading from the Geth blockchain", func() {
+
+	It("reads two blocks with incrementing numbers", func(done Done) {
+		addedBlock := make(chan core.Block, 10)
+		observer := &ObserverWithChannel{addedBlock}
+
+		var blockchain core.Blockchain = core.NewGethBlockchain(RunTimePath() + "/test_data_dir/geth.ipc")
+		blockchain.RegisterObserver(observer)
+
+		go blockchain.SubscribeToEvents()
+
+		firstBlock := <-addedBlock
+		Expect(firstBlock).ShouldNot(BeNil())
+		secondBlock := <-addedBlock
+		Expect(firstBlock.Number.Add(firstBlock.Number, big.NewInt(1))).Should(Equal(secondBlock.Number))
+
+		close(done)
+	}, 30)
+
+})

integration_test/integration_test_suite_test.go

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

scripts/setup

@@ -0,0 +1,6 @@
+#!/bin/bash
+echo "Deleting test blockchain"
+rm -rf test_data_dir
+echo "Creating test blockchain with a new account"
+mkdir test_data_dir
+geth --datadir test_data_dir --password .private_blockchain_password account new

scripts/start_private_blockchain

@@ -0,0 +1,2 @@
+#!/bin/bash
+geth --datadir test_data_dir --dev --nodiscover --mine --minerthreads 1 --maxpeers 0 --verbosity 3 --unlock 0 --password .private_blockchain_password --rpc