fix: retry lighter get tx (#116)

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---------

Co-authored-by: GregTheGreek <[email protected]>

Author: MakMuftic

go.mod

@@ -11,6 +11,7 @@ require (
 	github.com/ethereum/go-ethereum v1.16.2
 	github.com/golang/mock v1.6.0
 	github.com/gorilla/mux v1.8.1
+	github.com/hashicorp/go-retryablehttp v0.7.8
 	github.com/imdario/mergo v0.3.12
 	github.com/jellydator/ttlcache/v3 v3.3.0
 	github.com/libp2p/go-libp2p v0.38.2
@@ -71,7 +72,6 @@ require (
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.7.0 // indirect
 	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
-	github.com/hashicorp/go-retryablehttp v0.7.8 // indirect
 	github.com/holiman/bloomfilter/v2 v2.0.3 // indirect
 	github.com/holiman/uint256 v1.3.2 // indirect
 	github.com/mattn/go-runewidth v0.0.13 // indirect

protocol/lighter/api.go

@@ -1,15 +1,24 @@
 package lighter
 
 import (
+	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
 	"time"
+
+	"github.com/hashicorp/go-retryablehttp"
+	"github.com/rs/zerolog/log"
 )
 
 const (
-	LIGHTER_URL = "https://mainnet.zklighter.elliot.ai/api"
+	LIGHTER_URL             = "https://mainnet.zklighter.elliot.ai/api"
+	TX_NOT_FOUND_RETRIES    = 3
+	TX_NOT_FOUND_RETRY_WAIT = 500 * time.Millisecond
+	TX_NOT_FOUND_ERROR_CODE = 21500
+	TX_FOUND_STATUS_CODE    = 200
 )
 
 type TxType uint64
@@ -41,8 +50,8 @@ type LighterError struct {
 	Message string `json:"message"`
 }
 
-func (e *LighterError) Error() error {
-	return fmt.Errorf("lighter error: code %d, message: %s", e.Code, e.Message)
+func (e *LighterError) Error() string {
+	return fmt.Sprintf("lighter error: code %d, message: %s", e.Code, e.Message)
 }
 
 func (tx *LighterTx) UnmarshalJSON(data []byte) error {
@@ -54,9 +63,11 @@ func (tx *LighterTx) UnmarshalJSON(data []byte) error {
 	if tx.Type == TxTypeL2Transfer {
 		var t *Transfer
 		if err := json.Unmarshal([]byte(tx.Info), &t); err != nil {
-			return err
+			return fmt.Errorf("failed to unmarshal info: %w", err)
 		}
 		tx.Transfer = t
+	} else {
+		return fmt.Errorf("unsupported transaction type: %d", tx.Type)
 	}
 
 	return nil
@@ -67,13 +78,58 @@ type LighterAPI struct {
 }
 
 func NewLighterAPI() *LighterAPI {
+	retryClient := retryablehttp.NewClient()
+	retryClient.RetryMax = TX_NOT_FOUND_RETRIES - 1 // RetryMax is a number of retries after an initial attempt
+	retryClient.RetryWaitMin = TX_NOT_FOUND_RETRY_WAIT
+	retryClient.RetryWaitMax = TX_NOT_FOUND_RETRY_WAIT
+	retryClient.CheckRetry = LighterCheckRetry
+	retryClient.Logger = log.Logger
+
 	return &LighterAPI{
-		HTTPClient: &http.Client{
-			Timeout: 10 * time.Second,
-		},
+		HTTPClient: retryClient.StandardClient(),
 	}
 }
 
+// LighterCheckRetry checks if we should retry the request.
+// Retries when: error code is TX_NOT_FOUND_ERROR_CODE (21500) or response has code 200 but missing/empty info.
+func LighterCheckRetry(ctx context.Context, resp *http.Response, err error) (bool, error) {
+	if ctx.Err() != nil {
+		return false, ctx.Err()
+	}
+
+	if err != nil {
+		return false, err
+	}
+
+	if resp.StatusCode == http.StatusOK {
+		body, err := io.ReadAll(resp.Body)
+		if err != nil {
+			return false, err
+		}
+		resp.Body.Close()
+		resp.Body = io.NopCloser(bytes.NewReader(body))
+
+		// First try to unmarshal as LighterError
+		e := new(LighterError)
+		if err := json.Unmarshal(body, e); err == nil && e.Code == TX_NOT_FOUND_ERROR_CODE {
+			return true, nil
+		}
+
+		// Check if it's a LighterTx with code 200 but missing info
+		var raw map[string]interface{}
+		if err := json.Unmarshal(body, &raw); err == nil {
+			if code, ok := raw["code"].(float64); ok && code == TX_FOUND_STATUS_CODE {
+				info, hasInfo := raw["info"].(string)
+				if !hasInfo || info == "" {
+					return true, nil
+				}
+			}
+		}
+	}
+
+	return false, nil
+}
+
 // GetTx fetches transaction from the lighter API
 func (a *LighterAPI) GetTx(hash string) (*LighterTx, error) {
 	url := fmt.Sprintf("%s/v1/tx?by=hash&value=%s", LIGHTER_URL, hash)
@@ -94,11 +150,7 @@ func (a *LighterAPI) GetTx(hash string) (*LighterTx, error) {
 
 	s := new(LighterTx)
 	if err := json.Unmarshal(body, s); err != nil {
-		e := new(LighterError)
-		if err := json.Unmarshal(body, e); err != nil {
-			return nil, fmt.Errorf("failed to unmarshal response body: %s, with error: %w", string(body), err)
-		}
-		return nil, e.Error()
+		return nil, err
 	}
 
 	return s, nil

protocol/lighter/api_test.go

@@ -3,6 +3,7 @@ package lighter_test
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -113,3 +114,106 @@ func Test_LighterAPI_GetTx(t *testing.T) {
 		})
 	}
 }
+
+func Test_LighterCheckRetry(t *testing.T) {
+	tests := []struct {
+		name         string
+		statusCode   int
+		responseBody string
+		inputError   error
+		ctxCanceled  bool
+		wantRetry    bool
+		wantErr      bool
+	}{
+		{
+			name:         "retry on TX_NOT_FOUND_ERROR_CODE",
+			statusCode:   http.StatusOK,
+			responseBody: `{"code": 21500, "message": "transaction not found"}`,
+			wantRetry:    true,
+			wantErr:      false,
+		},
+		{
+			name:         "retry on code 200 with missing info",
+			statusCode:   http.StatusOK,
+			responseBody: `{"code": 200, "hash": "0xabc", "type": 12}`,
+			wantRetry:    true,
+			wantErr:      false,
+		},
+		{
+			name:         "retry on code 200 with empty info",
+			statusCode:   http.StatusOK,
+			responseBody: `{"code": 200, "hash": "0xabc", "type": 12, "info": ""}`,
+			wantRetry:    true,
+			wantErr:      false,
+		},
+		{
+			name:         "no retry on code 200 with valid info",
+			statusCode:   http.StatusOK,
+			responseBody: `{"code": 200, "hash": "0xabc", "type": 12, "info": "{\"USDCAmount\": 1000}"}`,
+			wantRetry:    false,
+			wantErr:      false,
+		},
+		{
+			name:         "no retry on different error code",
+			statusCode:   http.StatusOK,
+			responseBody: `{"code": 500, "message": "internal server error"}`,
+			wantRetry:    false,
+			wantErr:      false,
+		},
+		{
+			name:         "no retry on non-200 status",
+			statusCode:   http.StatusNotFound,
+			responseBody: `{"error": "not found"}`,
+			wantRetry:    false,
+			wantErr:      false,
+		},
+		{
+			name:       "no retry on input error",
+			inputError: errors.New("connection error"),
+			wantRetry:  false,
+			wantErr:    true,
+		},
+		{
+			name:        "error on context cancellation",
+			ctxCanceled: true,
+			wantRetry:   false,
+			wantErr:     true,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			ctx := context.Background()
+			if tc.ctxCanceled {
+				var cancel context.CancelFunc
+				ctx, cancel = context.WithCancel(ctx)
+				cancel()
+			}
+
+			var resp *http.Response
+			if tc.statusCode != 0 {
+				resp = &http.Response{
+					StatusCode: tc.statusCode,
+					Body:       io.NopCloser(bytes.NewReader([]byte(tc.responseBody))),
+					Header:     make(http.Header),
+				}
+			}
+
+			shouldRetry, err := lighter.LighterCheckRetry(ctx, resp, tc.inputError)
+
+			if tc.wantErr {
+				if err == nil {
+					t.Errorf("expected error, got nil")
+				}
+			} else {
+				if err != nil {
+					t.Errorf("unexpected error: %v", err)
+				}
+			}
+
+			if shouldRetry != tc.wantRetry {
+				t.Errorf("expected retry=%v, got retry=%v", tc.wantRetry, shouldRetry)
+			}
+		})
+	}
+}