Optimize getLogs GQL API (#198)

* Avoid joins with header and transaction tables while getting logs

* Update getLogs GQL API to accept multiple addresses

* Update version

* Update unit tests

pkg/graphql/client.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"strings"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
@@ -91,10 +92,16 @@ func NewClient(endpoint string) *Client {
 	return &Client{client: client}
 }
 
-func (c *Client) GetLogs(ctx context.Context, hash common.Hash, address *common.Address) ([]LogResponse, error) {
+func (c *Client) GetLogs(ctx context.Context, hash common.Hash, addresses []common.Address) ([]LogResponse, error) {
 	params := fmt.Sprintf(`blockHash: "%s"`, hash.String())
-	if address != nil {
-		params += fmt.Sprintf(`, contract: "%s"`, address.String())
+
+	if addresses != nil {
+		addressStrings := make([]string, len(addresses))
+		for i, address := range addresses {
+			addressStrings[i] = fmt.Sprintf(`"%s"`, address.String())
+		}
+
+		params += fmt.Sprintf(`, addresses: [%s]`, strings.Join(addressStrings, ","))
 	}
 
 	getLogsQuery := fmt.Sprintf(`query{

pkg/graphql/graphql.go

@@ -1037,12 +1037,15 @@ func (r *Resolver) GetStorageAt(ctx context.Context, args struct {
 
 func (r *Resolver) GetLogs(ctx context.Context, args struct {
 	BlockHash common.Hash
-	Contract  *common.Address
+	Addresses *[]common.Address
 }) (*[]*Log, error) {
-
 	var filter eth.ReceiptFilter
-	if args.Contract != nil {
-		filter.LogAddresses = []string{args.Contract.String()}
+
+	if args.Addresses != nil {
+		filter.LogAddresses = make([]string, len(*args.Addresses))
+		for i, address := range *args.Addresses {
+			filter.LogAddresses[i] = address.String()
+		}
 	}
 
 	// Begin tx

pkg/graphql/graphql_test.go

@@ -174,7 +174,7 @@ var _ = Describe("GraphQL", func() {
 
 	Describe("eth_getLogs", func() {
 		It("Retrieves logs that matches the provided blockHash and contract address", func() {
-			logs, err := client.GetLogs(ctx, blockHash, &contractAddress)
+			logs, err := client.GetLogs(ctx, blockHash, []common.Address{contractAddress})
 			Expect(err).ToNot(HaveOccurred())
 
 			expectedLogs := []graphql.LogResponse{
@@ -191,7 +191,7 @@ var _ = Describe("GraphQL", func() {
 		})
 
 		It("Retrieves logs for the failed receipt status that matches the provided blockHash and another contract address", func() {
-			logs, err := client.GetLogs(ctx, blockHash, &test_helpers.AnotherAddress2)
+			logs, err := client.GetLogs(ctx, blockHash, []common.Address{test_helpers.AnotherAddress2})
 			Expect(err).ToNot(HaveOccurred())
 
 			expectedLogs := []graphql.LogResponse{
@@ -207,6 +207,30 @@ var _ = Describe("GraphQL", func() {
 			Expect(logs).To(Equal(expectedLogs))
 		})
 
+		It("Retrieves logs that matches the provided blockHash and multiple contract addresses", func() {
+			logs, err := client.GetLogs(ctx, blockHash, []common.Address{contractAddress, test_helpers.AnotherAddress2})
+			Expect(err).ToNot(HaveOccurred())
+
+			expectedLogs := []graphql.LogResponse{
+				{
+					Topics:      test_helpers.MockLog1.Topics,
+					Data:        hexutil.Bytes(test_helpers.MockLog1.Data),
+					Transaction: graphql.TransactionResponse{Hash: test_helpers.MockTransactions[0].Hash()},
+					ReceiptCID:  test_helpers.Rct1CID.String(),
+					Status:      int32(test_helpers.MockReceipts[0].Status),
+				},
+				{
+					Topics:      test_helpers.MockLog6.Topics,
+					Data:        hexutil.Bytes(test_helpers.MockLog6.Data),
+					Transaction: graphql.TransactionResponse{Hash: test_helpers.MockTransactions[3].Hash()},
+					ReceiptCID:  test_helpers.Rct4CID.String(),
+					Status:      int32(test_helpers.MockReceipts[3].Status),
+				},
+			}
+
+			Expect(logs).To(Equal(expectedLogs))
+		})
+
 		It("Retrieves all the logs for the receipt that matches the provided blockHash and nil contract address", func() {
 			logs, err := client.GetLogs(ctx, blockHash, nil)
 			Expect(err).ToNot(HaveOccurred())
@@ -214,7 +238,7 @@ var _ = Describe("GraphQL", func() {
 		})
 
 		It("Retrieves logs with random hash", func() {
-			logs, err := client.GetLogs(ctx, randomHash, &contractAddress)
+			logs, err := client.GetLogs(ctx, randomHash, []common.Address{contractAddress})
 			Expect(err).ToNot(HaveOccurred())
 			Expect(len(logs)).To(Equal(0))
 		})

pkg/graphql/schema.go

@@ -343,7 +343,7 @@ const schema string = `
         getStorageAt(blockHash: Bytes32!, contract: Address!, slot: Bytes32!): StorageResult
 
         # Get contract logs by block hash and contract address.
-        getLogs(blockHash: Bytes32!, contract: Address): [Log!]
+        getLogs(blockHash: Bytes32!, addresses: [Address!]): [Log!]
 
         # PostGraphile alternative to get headers with transactions using block number or block hash.
         allEthHeaderCids(condition: EthHeaderCidCondition): EthHeaderCidsConnection