fix: load error images in image proxy before serving them

src/ui/proxy.rs

@@ -7,11 +7,11 @@ use crate::cache::image::manager::Error;
 
 pub static ERROR_IMAGE_LOADER: Once = Once::new();
 
-pub static mut ERROR_IMAGE_URL_IS_UNREACHABLE: Bytes = Bytes::new();
-pub static mut ERROR_IMAGE_URL_IS_NOT_AN_IMAGE: Bytes = Bytes::new();
-pub static mut ERROR_IMAGE_TOO_BIG: Bytes = Bytes::new();
-pub static mut ERROR_IMAGE_USER_QUOTA_MET: Bytes = Bytes::new();
-pub static mut ERROR_IMAGE_UNAUTHENTICATED: Bytes = Bytes::new();
+static mut ERROR_IMAGE_URL_IS_UNREACHABLE: Bytes = Bytes::new();
+static mut ERROR_IMAGE_URL_IS_NOT_AN_IMAGE: Bytes = Bytes::new();
+static mut ERROR_IMAGE_TOO_BIG: Bytes = Bytes::new();
+static mut ERROR_IMAGE_USER_QUOTA_MET: Bytes = Bytes::new();
+static mut ERROR_IMAGE_UNAUTHENTICATED: Bytes = Bytes::new();
 
 const ERROR_IMG_FONT_SIZE: u8 = 16;
 const ERROR_IMG_COLOR: &str = "Red";
@@ -33,6 +33,7 @@ pub fn load_error_images() {
 }
 
 pub fn map_error_to_image(error: &Error) -> Bytes {
+    load_error_images();
     unsafe {
         match error {
             Error::UrlIsUnreachable => ERROR_IMAGE_URL_IS_UNREACHABLE.clone(),

src/web/api/v1/contexts/proxy/mod.rs

@@ -9,7 +9,7 @@
 //! - Avoid storing images on the server.
 //!
 //! The proxy service is a simple cache that stores the images in memory.
-//! 
+//!
 //! **NOTICE:** For now, it only supports PNG images.
 //!
 //! **NOTICE:** The proxy service is not intended to be used as a general
@@ -20,13 +20,13 @@
 //! with the text "Sign in to see image" instead.
 //!
 //! # Example
-//! 
+//!
 //! The PNG image:
-//! 
+//!
 //! <https://raw.githubusercontent.com/torrust/torrust-index-backend/develop/docs/media/torrust_logo.png>
-//! 
+//!
 //! The percent encoded image URL:
-//! 
+//!
 //! ```text
 //! https%3A%2F%2Fraw.githubusercontent.com%2Ftorrust%2Ftorrust-index-backend%2Fdevelop%2Fdocs%2Fmedia%2Ftorrust_logo.png
 //! ```