Add ability to populate missing blocks

* The command populates up to the highest known block number
 * The anticipated use case is that the listener will be running
   in parallel to the populateBlocks command
    * This will mean that the listener is responsible for picking up
      new blocks, and the populateBlocks command is reposible for
      historical blocks
 * Reformat SQL statements

pkg/history/history_suite_test.go

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

pkg/history/populate_blocks.go

@@ -0,0 +1,15 @@
+package history
+
+import (
+	"github.com/8thlight/vulcanizedb/pkg/core"
+	"github.com/8thlight/vulcanizedb/pkg/repositories"
+)
+
+func PopulateBlocks(blockchain core.Blockchain, repository repositories.Repository, startingBlockNumber int64) int {
+	blockNumbers := repository.MissingBlockNumbers(startingBlockNumber, repository.MaxBlockNumber())
+	for _, blockNumber := range blockNumbers {
+		block := blockchain.GetBlockByNumber(blockNumber)
+		repository.CreateBlock(block)
+	}
+	return len(blockNumbers)
+}

pkg/history/populate_blocks_test.go

@@ -0,0 +1,69 @@
+package history_test
+
+import (
+	"github.com/8thlight/vulcanizedb/pkg/core"
+	"github.com/8thlight/vulcanizedb/pkg/fakes"
+	"github.com/8thlight/vulcanizedb/pkg/history"
+	"github.com/8thlight/vulcanizedb/pkg/repositories"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Populating blocks", func() {
+
+	It("fills in the only missing block", func() {
+		blocks := []core.Block{{Number: 1, Hash: "x012343"}}
+		blockchain := fakes.NewBlockchainWithBlocks(blocks)
+		repository := repositories.NewInMemory()
+		repository.CreateBlock(core.Block{Number: 2})
+
+		history.PopulateBlocks(blockchain, repository, 1)
+
+		block := repository.FindBlockByNumber(1)
+		Expect(block).NotTo(BeNil())
+		Expect(block.Hash).To(Equal("x012343"))
+	})
+
+	It("fills in two missing blocks", func() {
+		blockchain := fakes.NewBlockchainWithBlocks([]core.Block{
+			{Number: 4},
+			{Number: 5},
+			{Number: 8},
+			{Number: 10},
+			{Number: 13},
+		})
+		repository := repositories.NewInMemory()
+		repository.CreateBlock(core.Block{Number: 1})
+		repository.CreateBlock(core.Block{Number: 2})
+		repository.CreateBlock(core.Block{Number: 3})
+		repository.CreateBlock(core.Block{Number: 6})
+		repository.CreateBlock(core.Block{Number: 7})
+		repository.CreateBlock(core.Block{Number: 9})
+		repository.CreateBlock(core.Block{Number: 11})
+		repository.CreateBlock(core.Block{Number: 12})
+
+		history.PopulateBlocks(blockchain, repository, 5)
+
+		Expect(repository.BlockCount()).To(Equal(11))
+		Expect(repository.FindBlockByNumber(4)).To(BeNil())
+		Expect(repository.FindBlockByNumber(5)).NotTo(BeNil())
+		Expect(repository.FindBlockByNumber(8)).NotTo(BeNil())
+		Expect(repository.FindBlockByNumber(10)).NotTo(BeNil())
+		Expect(repository.FindBlockByNumber(13)).To(BeNil())
+	})
+
+	It("returns the number of blocks created", func() {
+		blockchain := fakes.NewBlockchainWithBlocks([]core.Block{
+			{Number: 4},
+			{Number: 5},
+		})
+		repository := repositories.NewInMemory()
+		repository.CreateBlock(core.Block{Number: 3})
+		repository.CreateBlock(core.Block{Number: 6})
+
+		numberOfBlocksCreated := history.PopulateBlocks(blockchain, repository, 3)
+
+		Expect(numberOfBlocksCreated).To(Equal(2))
+	})
+
+})