feat: added env read support

client/eth/client_test.go

@@ -2,11 +2,11 @@ package eth_test
 
 import (
 	"context"
-	"os"
 	"testing"
 	"time"
 
 	"github.com/berachain/offchain-sdk/client/eth"
+	"github.com/berachain/offchain-sdk/config/env"
 	"github.com/stretchr/testify/assert"
 
 	"github.com/ethereum/go-ethereum"
@@ -29,21 +29,29 @@ const (
 	TestModeEither
 )
 
+// setupClientTest loads environment variables and performs any necessary test setup.
+func setupClientTest(t *testing.T) {
+	t.Helper()
+	err := env.Load()
+	assert.NoError(t, err)
+}
+
 // NOTE: requires Ethereum chain rpc url at env var `ETH_RPC_URL` or `ETH_RPC_URL_WS`.
 func setUp(testMode int, t *testing.T) (*eth.ExtendedEthClient, error) {
+	setupClientTest(t)
 	rpcTimeout := 5 * time.Second
 	ctxWithTimeout, cancel := context.WithTimeout(context.Background(), rpcTimeout)
 	defer cancel()
 
 	var ethRPC string
 	switch testMode {
 	case TestModeWS:
-		ethRPC = os.Getenv("ETH_RPC_URL_WS")
+		ethRPC = env.GetEthWSURL()
 	case TestModeHTTP:
-		ethRPC = os.Getenv("ETH_RPC_URL")
+		ethRPC = env.GetEthRPCURL()
 	case TestModeEither:
-		if ethRPC = os.Getenv("ETH_RPC_URL_WS"); ethRPC == "" {
-			ethRPC = os.Getenv("ETH_RPC_URL")
+		if ethRPC = env.GetEthWSURL(); ethRPC == "" {
+			ethRPC = env.GetEthRPCURL()
 		}
 	default:
 		panic("invalid test mode")
@@ -130,7 +138,7 @@ func TestTxPoolContentFrom(t *testing.T) {
 	assert.NoError(t, err)
 
 	ctx := context.Background()
-	addrStr := os.Getenv("ETH_ADDR")
+	addrStr := env.GetAddressToListen()
 	if addrStr == "" {
 		t.Skipf("Skipping test: no eth address provided")
 	}

client/eth/connection_pool_test.go

@@ -3,26 +3,26 @@ package eth_test
 import (
 	"bytes"
 	"io"
-	"os"
 	"testing"
 
 	"github.com/berachain/offchain-sdk/client/eth"
+	"github.com/berachain/offchain-sdk/config/env"
 	"github.com/berachain/offchain-sdk/log"
 	"github.com/stretchr/testify/require"
 )
 
-var (
-	HTTPURL = os.Getenv("ETH_HTTP_URL")
-	WSURL   = os.Getenv("ETH_WS_URL")
-)
-
-/******************************* HELPER FUNCTIONS ***************************************/
+// setupTest loads environment variables and performs any necessary test setup.
+func setupTest(t *testing.T) {
+	t.Helper()
+	err := env.Load()
+	require.NoError(t, err)
+}
 
-// NOTE: requires chain rpc url at env var `ETH_HTTP_URL` and `ETH_WS_URL`.
+// NOTE: requires chain rpc url at env var `ETH_RPC_URL` and `ETH_WS_URL`.
 func checkEnv(t *testing.T) {
-	ethHTTPRPC := os.Getenv("ETH_HTTP_URL")
-	ethWSRPC := os.Getenv("ETH_WS_URL")
-	if ethHTTPRPC == "" || ethWSRPC == "" {
+	ethRPC := env.GetEthRPCURL()
+	ethWS := env.GetEthWSURL()
+	if ethRPC == "" || ethWS == "" {
 		t.Skipf("Skipping test: no eth rpc url provided")
 	}
 }
@@ -58,7 +58,7 @@ func TestNewConnectionPoolImpl_MissingURLs(t *testing.T) {
 // TestNewConnectionPoolImpl_MissingWSURLs tests the case when the WS URLs are missing.
 func TestNewConnectionPoolImpl_MissingWSURLs(t *testing.T) {
 	cfg := eth.ConnectionPoolConfig{
-		EthHTTPURLs: []string{HTTPURL},
+		EthHTTPURLs: []string{env.GetEthRPCURL()},
 	}
 	var logBuffer bytes.Buffer
 	pool, err := Init(cfg, &logBuffer, t)
@@ -71,9 +71,10 @@ func TestNewConnectionPoolImpl_MissingWSURLs(t *testing.T) {
 // TestNewConnectionPoolImpl tests the case when the URLs are provided.
 // It should the expected behavior.
 func TestNewConnectionPoolImpl(t *testing.T) {
+	setupTest(t)
 	cfg := eth.ConnectionPoolConfig{
-		EthHTTPURLs: []string{HTTPURL},
-		EthWSURLs:   []string{WSURL},
+		EthHTTPURLs: []string{env.GetEthRPCURL()},
+		EthWSURLs:   []string{env.GetEthWSURL()},
 	}
 	var logBuffer bytes.Buffer
 	pool, err := Init(cfg, &logBuffer, t)
@@ -86,8 +87,9 @@ func TestNewConnectionPoolImpl(t *testing.T) {
 // TestGetHTTP tests the retrieval of the HTTP client when it
 // has been set and the connection has been established.
 func TestGetHTTP(t *testing.T) {
+	setupTest(t)
 	cfg := eth.ConnectionPoolConfig{
-		EthHTTPURLs: []string{HTTPURL},
+		EthHTTPURLs: []string{env.GetEthRPCURL()},
 	}
 	var logBuffer bytes.Buffer
 	pool, _ := Init(cfg, &logBuffer, t)
@@ -102,9 +104,10 @@ func TestGetHTTP(t *testing.T) {
 // TestGetWS tests the retrieval of the HTTP client when it
 // has been set and the connection has been established.
 func TestGetWS(t *testing.T) {
+	setupTest(t)
 	cfg := eth.ConnectionPoolConfig{
-		EthHTTPURLs: []string{HTTPURL},
-		EthWSURLs:   []string{WSURL},
+		EthHTTPURLs: []string{env.GetEthRPCURL()},
+		EthWSURLs:   []string{env.GetEthWSURL()},
 	}
 	var logBuffer bytes.Buffer
 	pool, _ := Init(cfg, &logBuffer, t)
@@ -120,8 +123,9 @@ func TestGetWS(t *testing.T) {
 // TestGetWS_WhenItIsNotSet tests the retrieval of the WS client when
 // no WS URLs have been provided.
 func TestGetWS_WhenItIsNotSet(t *testing.T) {
+	setupTest(t)
 	cfg := eth.ConnectionPoolConfig{
-		EthHTTPURLs: []string{HTTPURL},
+		EthHTTPURLs: []string{env.GetEthRPCURL()},
 	}
 	var logBuffer bytes.Buffer
 	pool, _ := Init(cfg, &logBuffer, t)

config/env/env.go

@@ -1,3 +1,82 @@
 package env
 
-// TODO support reading .env
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/joho/godotenv"
+)
+
+const (
+	// Ethereum RPC URLs.
+	EnvEthRPCURL   = "ETH_RPC_URL"
+	EnvEthWSURL    = "ETH_WS_URL"
+	EnvEthRPCURLWS = "ETH_RPC_URL_WS" // Alternative WS URL used in some tests
+
+	// Event listening configuration.
+	EnvEventName     = "EVENT_NAME"
+	EnvAddressListen = "ADDRESS_TO_LISTEN"
+)
+
+// Loads environment variables from .env file.
+func Load() error {
+	// Try loading from current directory first
+	err := godotenv.Load()
+	if err == nil {
+		return nil
+	}
+
+	// Then If that fails, try to find .env in
+	// parent directories.
+	dir, err := os.Getwd()
+	if err != nil {
+		return err
+	}
+
+	for {
+		envPath := filepath.Join(dir, ".env")
+		if _, statErr := os.Stat(envPath); statErr == nil {
+			return godotenv.Load(envPath)
+		}
+
+		parent := filepath.Dir(dir)
+		if parent == dir {
+			break
+		}
+		dir = parent
+	}
+
+	// If we get here, we couldn't find the .env file
+	// But we don't return an error because the env vars
+	// might be actually set in the system in which case
+	// we don't need the .env file.
+	return nil
+}
+
+// Loads environment variables from the specified file.
+func LoadFile(filename string) error {
+	return godotenv.Load(filename)
+}
+
+// Returns the Ethereum RPC URL.
+func GetEthRPCURL() string {
+	return os.Getenv(EnvEthRPCURL)
+}
+
+// Returns the Ethereum WebSocket URL.
+func GetEthWSURL() string {
+	if url := os.Getenv(EnvEthRPCURLWS); url != "" {
+		return url
+	}
+	return os.Getenv(EnvEthWSURL)
+}
+
+// Returns the event name to listen for.
+func GetEventName() string {
+	return os.Getenv(EnvEventName)
+}
+
+// Returns the contract address to listen to.
+func GetAddressToListen() string {
+	return os.Getenv(EnvAddressListen)
+}

config/env/env_test.go

@@ -0,0 +1,60 @@
+package env
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestEnv(t *testing.T) {
+	t.Run("test loading from .env file", func(t *testing.T) {
+		// Creating a temporary .env file for this test
+		dir := t.TempDir()
+		envFile := filepath.Join(dir, ".env")
+		err := os.WriteFile(envFile, []byte(`
+ETH_RPC_URL=http://localhost:8545
+ETH_WS_URL=ws://localhost:8546
+ETH_RPC_URL_WS=ws://localhost:8547
+EVENT_NAME=NumberChanged(uint256)
+ADDRESS_TO_LISTEN=0x5793a71D3eF074f71dCC21216Dbfd5C0e780132c
+`), 0644)
+		require.NoError(t, err)
+
+		// Loading the env file
+		err = LoadFile(envFile)
+		require.NoError(t, err)
+
+		// Testing each getter
+		require.Equal(t, "http://localhost:8545", GetEthRPCURL())
+		require.Equal(t, "ws://localhost:8547", GetEthWSURL(), "should prefer ETH_RPC_URL_WS")
+
+		// Clearing ETH_RPC_URL_WS and verifying fallback to ETH_WS_URL
+		os.Unsetenv(EnvEthRPCURLWS)
+		require.Equal(t, "ws://localhost:8546", GetEthWSURL(), "should fallback to ETH_WS_URL")
+
+		require.Equal(t, "NumberChanged(uint256)", GetEventName())
+		require.Equal(t, "0x5793a71D3eF074f71dCC21216Dbfd5C0e780132c", GetAddressToListen())
+	})
+
+	t.Run("test loading non-existent file", func(t *testing.T) {
+		err := LoadFile("non-existent.env")
+		require.Error(t, err)
+	})
+
+	t.Run("test loading with missing values", func(t *testing.T) {
+		// Clearing all env vars first
+		os.Unsetenv(EnvEthRPCURL)
+		os.Unsetenv(EnvEthWSURL)
+		os.Unsetenv(EnvEthRPCURLWS)
+		os.Unsetenv(EnvEventName)
+		os.Unsetenv(EnvAddressListen)
+
+		// Testing empty values
+		require.Empty(t, GetEthRPCURL())
+		require.Empty(t, GetEthWSURL())
+		require.Empty(t, GetEventName())
+		require.Empty(t, GetAddressToListen())
+	})
+}

go.mod

@@ -18,6 +18,7 @@ require (
 	github.com/holiman/uint256 v1.2.4
 	github.com/huandu/skiplist v1.2.0
 	github.com/jellydator/ttlcache/v2 v2.11.1
+	github.com/joho/godotenv v1.5.1
 	github.com/prometheus/client_golang v1.17.0
 	github.com/redis/go-redis/v9 v9.5.1
 	github.com/rs/zerolog v1.31.0

go.sum

@@ -418,6 +418,8 @@ github.com/jjti/go-spancheck v0.6.2 h1:iYtoxqPMzHUPp7St+5yA8+cONdyXD3ug6KK15n7Pk
 github.com/jjti/go-spancheck v0.6.2/go.mod h1:+X7lvIrR5ZdUTkxFYqzJ0abr8Sb5LOo80uOhWNqIrYA=
 github.com/jmespath/go-jmespath v0.4.0/go.mod h1:T8mJZnbsbmF+m6zOOFylbeCJqk5+pHWvzYPziyZiYoo=
 github.com/jmespath/go-jmespath/internal/testify v1.5.1/go.mod h1:L3OGu8Wl2/fWfCI6z80xFu9LTZmf1ZRjMHUOPmWr69U=
+github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
+github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
 github.com/json-iterator/go v1.1.6/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
 github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
 github.com/juju/errors v0.0.0-20181118221551-089d3ea4e4d5/go.mod h1:W54LbzXuIE0boCoNJfwqpmkKJ1O4TCTZMetAt6jGk7Q=