made optimism endpoint configurable and changed default (#502)

.github/workflows/unit-tests.yml

@@ -64,6 +64,7 @@ jobs:
         env:
           ETH_MAINNET_ENDPOINT: ${{ secrets.ETH_MAINNET_ENDPOINT }}
           ETH_SEPOLIA_ENDPOINT: ${{ secrets.ETH_SEPOLIA_ENDPOINT }}
+          ETH_OPTIMISM_ENDPOINT: ${{ secrets.ETH_OPTIMISM_ENDPOINT }}
         run: ./scripts/run-unit-tests.sh
 
       - name: Upload code coverage

Makefile

@@ -1,4 +1,5 @@
 GOPATH ?= $(shell go env GOPATH)
+NPM_DIR = $(shell npm config get prefix)
 
 .PHONY: all
 all: install
@@ -14,7 +15,7 @@ lint-shell:
 
 .PHONY: lint-solidity
 lint-solidity: 
-	"$$(npm config get prefix)/bin/solhint" $$(find ethereum -name '*.sol' -not -path '**/@openzeppelin/**')
+	"$(NPM_DIR)/bin/solhint" $$(find ethereum -name '*.sol' -not -path '**/@openzeppelin/**')
 
 .PHONY: lint
 lint: lint-go lint-shell lint-solidity
@@ -30,7 +31,8 @@ format-shell:
 
 .PHONY: format-solidity
 format-solidity:
-	"$$(npm config get prefix)/bin/prettier" --print-width 100 --write \
+	"$(NPM_DIR)/bin/prettier" --print-width 100 --write \
+		--plugin="$(NPM_DIR)/lib/node_modules/prettier-plugin-solidity/src/index.js" \
 		$$(find ethereum -name '*.sol' -not -path '**/@openzeppelin/**')
 
 .PHONY: format

pricefeed/pricefeed.go

@@ -8,6 +8,7 @@ package pricefeed
 import (
 	"context"
 	"errors"
+	"os"
 	"time"
 
 	"github.com/cockroachdb/apd/v3"
@@ -21,10 +22,10 @@ import (
 )
 
 const (
-	// optimismEndpoint is an RPC endpoint for optimism mainnet. Note that we
+	// fallbackOptimismEndpoint is an RPC endpoint for optimism mainnet. Note that we
 	// tried https://mainnet.optimism.io first, but it is severely rate limited
 	// to around 2 requests/second.
-	optimismEndpoint = "https://1rpc.io/op"
+	fallbackOptimismEndpoint = "https://optimism.blockpi.network/v1/rpc/public"
 
 	// https://data.chain.link/optimism/mainnet/crypto-usd/eth-usd
 	chainlinkETHToUSDProxy = "0x13e3ee699d1909e989722e753853ae30b17e08c5"
@@ -45,6 +46,14 @@ type PriceFeed struct {
 	UpdatedAt   time.Time
 }
 
+func getOptimismEndpoint() string {
+	endpoint := os.Getenv("ETH_OPTIMISM_ENDPOINT")
+	if endpoint == "" {
+		endpoint = fallbackOptimismEndpoint
+	}
+	return endpoint
+}
+
 // GetETHUSDPrice returns the current ETH/USD price from the Chainlink oracle.
 func GetETHUSDPrice(ctx context.Context, ec *ethclient.Client) (*PriceFeed, error) {
 	chainID, err := ec.ChainID(ctx)
@@ -56,7 +65,7 @@ func GetETHUSDPrice(ctx context.Context, ec *ethclient.Client) (*PriceFeed, erro
 	case common.OpMainnetChainID:
 		// No extra work to do
 	case common.MainnetChainID, common.SepoliaChainID:
-		ec, err = ethclient.Dial(optimismEndpoint)
+		ec, err = ethclient.Dial(getOptimismEndpoint())
 		if err != nil {
 			return nil, err
 		}
@@ -86,7 +95,7 @@ func GetXMRUSDPrice(ctx context.Context, ec *ethclient.Client) (*PriceFeed, erro
 		// No extra work to do
 	case common.MainnetChainID, common.SepoliaChainID:
 		// Push stagenet/sepolia users to a mainnet endpoint
-		ec, err = ethclient.Dial(optimismEndpoint)
+		ec, err = ethclient.Dial(getOptimismEndpoint())
 		if err != nil {
 			return nil, err
 		}

pricefeed/pricefeed_test.go

@@ -20,7 +20,7 @@ func init() {
 }
 
 func newOptimismClient(t *testing.T) *ethclient.Client {
-	ec, err := ethclient.Dial(optimismEndpoint)
+	ec, err := ethclient.Dial(getOptimismEndpoint())
 	require.NoError(t, err)
 	t.Cleanup(func() {
 		ec.Close()