allow resizing & reformatting of animated images

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rusty_resizer"
-version = "0.1.9"
+version = "0.4.0"
 edition = "2021"
 
 [lib]
@@ -30,5 +30,6 @@ url = "2.2.2"
 
 [dev-dependencies]
 actix-rt = "2.7.0"
-reqwest = "0.11.10"
 actix-service = "2.0.2"
+gif = "0.12.0"
+reqwest = "0.11.10"

src/img/resizable.rs

@@ -30,7 +30,12 @@ impl ResizableImage {
         };
 
         if !(width == self.wand.get_image_width() && height == self.wand.get_image_height()) {
-            self.wand.thumbnail_image(width, height);
+            // if image has multiple frames use fit to resize the entire scene
+            if self.wand.get_image_scene() > 0 {
+                self.wand.fit(width, height);
+            } else {
+                self.wand.thumbnail_image(width, height);
+            }
         }
     }
 
@@ -58,17 +63,15 @@ impl ResizableImage {
             .map_err(|_| ImageError::FailedWrite)?;
 
         self.wand
-            .write_image_blob(format.extensions_str()[0])
+            .write_images_blob(format.extensions_str()[0])
             .map_err(|_| ImageError::FailedWrite)
     }
 
     pub fn format(&self) -> Result<ImageFormat, ImageError> {
         self.wand
             .get_image_format()
             .map_err(|_| ImageError::InvalidFormat)
-            .and_then(|format| {
-                ImageFormat::from_extension(&format).ok_or(ImageError::InvalidFormat)
-            })
+            .and_then(|format| ImageFormat::from_extension(format).ok_or(ImageError::InvalidFormat))
     }
 
     pub fn mime_type(self) -> Result<&'static str, ImageError> {

tests/resize.rs

@@ -120,6 +120,65 @@ async fn test_resize_can_resize_an_image() {
     assert_eq!(height, 100, "height is equal to 100px");
 }
 
+#[actix_rt::test]
+async fn test_resize_can_resize_an_animated_image() {
+    // Arrange
+    let address = spawn_app();
+    let client = reqwest::Client::new();
+    let test_image_one = "https://raw.githubusercontent.com/walterbm/rusty-resizer/main/tests/fixtures/test-image-animated.gif";
+
+    // Act
+    let response = client
+        .get(format!(
+            "{}/resize?source={}&width=100",
+            address, test_image_one
+        ))
+        .send()
+        .await
+        .expect("Failed to execute request.");
+
+    // Assert
+    assert!(response.status().is_success());
+    assert_eq!(
+        response.headers().get("Content-Type").unwrap(),
+        "image/gif",
+        "content type is equal to image/gif"
+    );
+    assert_eq!(
+        response.headers().get("Cache-Control").unwrap(),
+        "max-age=3600",
+        "cache control max age is equal to 3600"
+    );
+    assert!(
+        response.headers().get("Vary").is_none(),
+        "response does not vary by request 'accept' header"
+    );
+
+    let bytes = response
+        .bytes()
+        .await
+        .expect("Failed to read response bytes");
+
+    let mut options = gif::DecodeOptions::new();
+    options.set_color_output(gif::ColorOutput::RGBA);
+
+    let mut gif_decoder = options
+        .read_info(Cursor::new(bytes))
+        .expect("Failed to decode animated image");
+
+    let mut frame_counter = 0;
+    while let Some(frame) = gif_decoder
+        .read_next_frame()
+        .expect("Failed to decode image frame")
+    {
+        frame_counter += 1;
+        assert_eq!(frame.width, 99, "width is equal to 99px");
+        assert_eq!(frame.height, 57, "height is equal to 57px");
+    }
+
+    assert_eq!(frame_counter, 55, "resized animated image has 55 frames");
+}
+
 #[actix_rt::test]
 async fn test_resize_can_resize_an_image_with_only_one_dimension_and_preserve_aspect_ratio() {
     // Arrange