Get transactions (#45)

* Make transactions requests in parallel

* Update transaction error handling

integration_test/geth_blockchain_test.go

@@ -3,6 +3,7 @@ package integration_test
 import (
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
+	"github.com/vulcanize/vulcanizedb/pkg/core"
 	"github.com/vulcanize/vulcanizedb/pkg/datastore/inmemory"
 	"github.com/vulcanize/vulcanizedb/pkg/geth"
 	"github.com/vulcanize/vulcanizedb/pkg/history"
@@ -28,8 +29,10 @@ var _ = Describe("Reading from the Geth blockchain", func() {
 	}, 30)
 
 	It("retrieves the genesis block and first block", func(done Done) {
-		genesisBlock := blockchain.GetBlockByNumber(int64(0))
-		firstBlock := blockchain.GetBlockByNumber(int64(1))
+		genesisBlock, err := blockchain.GetBlockByNumber(int64(0))
+		Expect(err).ToNot(HaveOccurred())
+		firstBlock, err := blockchain.GetBlockByNumber(int64(1))
+		Expect(err).ToNot(HaveOccurred())
 		lastBlockNumber := blockchain.LastBlock()
 
 		Expect(genesisBlock.Number).To(Equal(int64(0)))
@@ -40,14 +43,27 @@ var _ = Describe("Reading from the Geth blockchain", func() {
 
 	It("retrieves the node info", func(done Done) {
 		node := blockchain.Node()
-		devNetworkNodeId := float64(1)
+		mainnetID := float64(1)
 
 		Expect(node.GenesisBlock).ToNot(BeNil())
-		Expect(node.NetworkID).To(Equal(devNetworkNodeId))
+		Expect(node.NetworkID).To(Equal(mainnetID))
 		Expect(len(node.ID)).ToNot(BeZero())
 		Expect(node.ClientName).ToNot(BeZero())
 
 		close(done)
 	}, 15)
 
+	//Benchmarking test: remove skip to test performance of block retrieval
+	XMeasure("retrieving n blocks", func(b Benchmarker) {
+		b.Time("runtime", func() {
+			var blocks []core.Block
+			n := 10
+			for i := 5327459; i > 5327459-n; i-- {
+				block, err := blockchain.GetBlockByNumber(int64(i))
+				Expect(err).ToNot(HaveOccurred())
+				blocks = append(blocks, block)
+			}
+			Expect(len(blocks)).To(Equal(n))
+		})
+	}, 10)
 })