fix(httpclient): fix HTTP 0 status and restore FS session default

- Guard isCloudflareChallenge with directStatus >= 400 to prevent
  overriding status to 0 when no direct request was made
- When FS returns challenge page without a prior direct status,
  return an error instead of silently passing HTTP 0
- Restore default FS session ID to 'goyomi' — without a session,
  each request spawns a new Chrome, causing timeouts under load
- Add Message field to FlareSolverrResponse for better error reporting
- Document FLARESOLVERR_SESSION env var: shared session = fast after
  1st request, but serializes. Set empty for parallel (resource-heavy).

.env.example

@@ -8,7 +8,7 @@ DATABASE_URL=postgres://goyomi:goyomi@postgres:5432/goyomi?sslmode=disable
 FLARESOLVERR_URL=http://flaresolverr:8191
 FLARESOLVERR_LOG_LEVEL=info
 FLARESOLVERR_PROXY=0
-FLARESOLVERR_SESSION=goyomi
+FLARESOLVERR_SESSION=goyomi     # FS browser session ID; shared session = faster after 1st request. Set empty to disable (each request gets a fresh browser = parallel but resource-heavy)
 ADDR=:3300
 
 # Connection pool

internal/httpclient/client.go

@@ -211,12 +211,13 @@ func (c *Client) doFS(req *http.Request, directStatus int) (*http.Response, erro
 		}
 	}
 
-	// When FlareSolverr returns status 200, Chrome rendered the page.
-	// Check if the body actually contains Cloudflare challenge indicators
-	// rather than relying on structural heuristics (<pre> wrapper).
-	if statusCode == 200 {
-		if isCloudflareChallenge([]byte(rawBody)) {
+	// If FS returned the challenge page instead of the real content,
+	// reject it (HTTP 0 case when directStatus=0).
+	if statusCode == 200 && isCloudflareChallenge([]byte(rawBody)) {
+		if directStatus >= 400 {
 			statusCode = directStatus
+		} else {
+			return nil, fmt.Errorf("FlareSolverr returned challenge page for %s", rawURL)
 		}
 	}
 

internal/httpclient/flaresolverr.go

@@ -39,6 +39,7 @@ type flareSolverrRequest struct {
 
 type FlareSolverrResponse struct {
 	Status   string `json:"status"`
+	Message  string `json:"message,omitempty"`
 	Solution struct {
 		Response string          `json:"response"`
 		Cookies  []fsCookie      `json:"cookies"`
@@ -107,7 +108,11 @@ func (f *FlareSolverrClient) GetRaw(ctx context.Context, url string) (body strin
 		return "", 0, nil, nil, "", err
 	}
 	if fsResp.Status != "ok" {
-		return "", 0, nil, nil, "", fmt.Errorf("flaresolverr: status %q", fsResp.Status)
+		msg := fsResp.Message
+		if msg == "" {
+			msg = fmt.Sprintf("status %q", fsResp.Status)
+		}
+		return "", 0, nil, nil, "", fmt.Errorf("flaresolverr: %s", msg)
 	}
 
 	for _, c := range fsResp.Solution.Cookies {
@@ -170,7 +175,11 @@ func (f *FlareSolverrClient) request(ctx context.Context, cmd, url, body string,
 		return "", nil, err
 	}
 	if fsResp.Status != "ok" {
-		return "", nil, fmt.Errorf("flaresolverr: status %q", fsResp.Status)
+		msg := fsResp.Message
+		if msg == "" {
+			msg = fmt.Sprintf("status %q", fsResp.Status)
+		}
+		return "", nil, fmt.Errorf("flaresolverr: %s", msg)
 	}
 
 	for _, c := range fsResp.Solution.Cookies {