perf: increase concurrent renders limit from 4 to 8

- Add magic bytes validation for extracted CBR images
- Add hex dump for debugging invalid images
- Show first entries when listing CBR archive
- Remove unused structs and functions from settings.rs
- Add -y flag to unrar for auto-confirm

apps/api/src/main.rs

@@ -85,7 +85,7 @@ async fn main() -> anyhow::Result<()> {
         meili_url: Arc::from(config.meili_url),
         meili_master_key: Arc::from(config.meili_master_key),
         page_cache: Arc::new(Mutex::new(LruCache::new(NonZeroUsize::new(512).expect("non-zero")))),
-        page_render_limit: Arc::new(Semaphore::new(4)),
+        page_render_limit: Arc::new(Semaphore::new(8)),
         metrics: Arc::new(Metrics::new()),
         read_rate_limit: Arc::new(Mutex::new(ReadRateLimit {
             window_started_at: Instant::now(),

apps/api/src/pages.rs

@@ -363,6 +363,11 @@ fn extract_cbr_page(abs_path: &str, page_number: u32) -> Result<Vec<u8>, ApiErro
         .map(|s| s.to_string())
         .collect();
     entries.sort();
+    
+    // Debug: show first few entries
+    if entries.len() > 0 {
+        debug!("First 5 entries in CBR {}: {:?}", abs_path, &entries[..entries.len().min(5)]);
+    }
     debug!("Found {} images in CBR {}", entries.len(), abs_path);
 
     let index = page_number as usize - 1;
@@ -375,6 +380,7 @@ fn extract_cbr_page(abs_path: &str, page_number: u32) -> Result<Vec<u8>, ApiErro
     let page_output = std::process::Command::new("unrar")
         .arg("p")
         .arg("-inul")
+        .arg("-y")
         .arg(abs_path)
         .arg(selected)
         .output()
@@ -387,8 +393,45 @@ fn extract_cbr_page(abs_path: &str, page_number: u32) -> Result<Vec<u8>, ApiErro
         error!("unrar could not extract page {} from {}: {}", selected, abs_path, stderr);
         return Err(ApiError::internal("unrar could not extract page"));
     }
-    debug!("Successfully extracted {} bytes from CBR page {}", page_output.stdout.len(), page_number);
-    Ok(page_output.stdout)
+    
+    let extracted_data = &page_output.stdout;
+    debug!("Extracted {} bytes from CBR page {}", extracted_data.len(), page_number);
+    
+    // Verify it's actually an image by checking magic bytes
+    if extracted_data.len() < 1000 {
+        // Show first few bytes for debugging
+        let preview: Vec<u8> = extracted_data.iter().take(32).copied().collect();
+        let hex_preview: String = preview.iter().map(|b| format!("{:02x}", b)).collect();
+        error!("Extracted data too small ({} bytes) for page {} from {} - first bytes: {}", 
+            extracted_data.len(), page_number, abs_path, hex_preview);
+        return Err(ApiError::internal("extracted data too small - not a valid image"));
+    }
+    
+    // Check magic bytes to verify it's an image
+    let is_valid_image = extracted_data.len() > 4 && (
+        // JPEG
+        extracted_data.starts_with(&[0xFF, 0xD8, 0xFF]) ||
+        // PNG
+        extracted_data.starts_with(&[0x89, 0x50, 0x4E, 0x47]) ||
+        // GIF
+        extracted_data.starts_with(b"GIF87a") || extracted_data.starts_with(b"GIF89a") ||
+        // WebP
+        extracted_data.starts_with(b"RIFF") && extracted_data.len() > 12 && &extracted_data[8..12] == b"WEBP" ||
+        // TIFF
+        extracted_data.starts_with(&[0x49, 0x49, 0x2A, 0x00]) || extracted_data.starts_with(&[0x4D, 0x4D, 0x00, 0x2A])
+    );
+    
+    if !is_valid_image {
+        // Show first few bytes for debugging
+        let preview: Vec<u8> = extracted_data.iter().take(32).copied().collect();
+        let hex_preview: String = preview.iter().map(|b| format!("{:02x}", b)).collect();
+        error!("Extracted data for page {} from {} is not a valid image format. First bytes: {} (size: {})", 
+            page_number, abs_path, hex_preview, extracted_data.len());
+        return Err(ApiError::internal("extracted data is not a valid image"));
+    }
+    
+    debug!("Successfully extracted {} bytes from CBR page {}", extracted_data.len(), page_number);
+    Ok(extracted_data.to_vec())
 }
 
 fn render_pdf_page(abs_path: &str, page_number: u32, width: u32) -> Result<Vec<u8>, ApiError> {

apps/api/src/settings.rs

@@ -1,6 +1,5 @@
 use axum::{
-    extract::{Query, State},
-    response::IntoResponse,
+    extract::State,
     routing::{get, post},
     Json, Router,
 };
@@ -10,40 +9,24 @@ use sqlx::Row;
 
 use crate::{error::ApiError, AppState};
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
-pub struct ImageProcessingSettings {
-    pub format: String,
-    pub quality: u8,
-    pub filter: String,
-    pub max_width: u32,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize)]
-pub struct CacheSettings {
-    pub enabled: bool,
-    pub directory: String,
-    pub max_size_mb: u32,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize)]
-pub struct LimitsSettings {
-    pub concurrent_renders: u8,
-    pub timeout_seconds: u8,
-    pub rate_limit_per_second: u16,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize)]
-pub struct AppSettings {
-    pub image_processing: ImageProcessingSettings,
-    pub cache: CacheSettings,
-    pub limits: LimitsSettings,
-}
-
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct UpdateSettingRequest {
     pub value: Value,
 }
 
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ClearCacheResponse {
+    pub success: bool,
+    pub message: String,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct CacheStats {
+    pub total_size_mb: f64,
+    pub file_count: u64,
+    pub directory: String,
+}
+
 pub fn settings_routes() -> Router<AppState> {
     Router::new()
         .route("/settings", get(get_settings))
@@ -108,12 +91,6 @@ async fn update_setting(
     Ok(Json(value))
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
-pub struct ClearCacheResponse {
-    pub success: bool,
-    pub message: String,
-}
-
 async fn clear_cache(State(_state): State<AppState>) -> Result<Json<ClearCacheResponse>, ApiError> {
     let cache_dir = std::env::var("IMAGE_CACHE_DIR")
         .unwrap_or_else(|_| "/tmp/stripstream-image-cache".to_string());
@@ -143,13 +120,6 @@ async fn clear_cache(State(_state): State<AppState>) -> Result<Json<ClearCacheRe
     Ok(Json(result))
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
-pub struct CacheStats {
-    pub total_size_mb: f64,
-    pub file_count: u64,
-    pub directory: String,
-}
-
 async fn get_cache_stats(State(_state): State<AppState>) -> Result<Json<CacheStats>, ApiError> {
     let cache_dir = std::env::var("IMAGE_CACHE_DIR")
         .unwrap_or_else(|_| "/tmp/stripstream-image-cache".to_string());
@@ -201,60 +171,3 @@ async fn get_cache_stats(State(_state): State<AppState>) -> Result<Json<CacheSta
 
     Ok(Json(stats))
 }
-
-pub async fn get_settings_from_db(
-    pool: &sqlx::PgPool,
-) -> Result<AppSettings, ApiError> {
-    let settings = get_settings_from_db_raw(pool).await?;
-    
-    let image_processing = settings
-        .get("image_processing")
-        .and_then(|v| serde_json::from_value(v.clone()).ok())
-        .unwrap_or_else(|| ImageProcessingSettings {
-            format: "webp".to_string(),
-            quality: 85,
-            filter: "lanczos3".to_string(),
-            max_width: 2160,
-        });
-
-    let cache = settings
-        .get("cache")
-        .and_then(|v| serde_json::from_value(v.clone()).ok())
-        .unwrap_or_else(|| CacheSettings {
-            enabled: true,
-            directory: "/tmp/stripstream-image-cache".to_string(),
-            max_size_mb: 10000,
-        });
-
-    let limits = settings
-        .get("limits")
-        .and_then(|v| serde_json::from_value(v.clone()).ok())
-        .unwrap_or_else(|| LimitsSettings {
-            concurrent_renders: 4,
-            timeout_seconds: 12,
-            rate_limit_per_second: 120,
-        });
-
-    Ok(AppSettings {
-        image_processing,
-        cache,
-        limits,
-    })
-}
-
-async fn get_settings_from_db_raw(
-    pool: &sqlx::PgPool,
-) -> Result<std::collections::HashMap<String, Value>, ApiError> {
-    let rows = sqlx::query(r#"SELECT key, value FROM app_settings"#)
-        .fetch_all(pool)
-        .await?;
-
-    let mut settings = std::collections::HashMap::new();
-    for row in rows {
-        let key: String = row.get("key");
-        let value: Value = row.get("value");
-        settings.insert(key, value);
-    }
-
-    Ok(settings)
-}