Refactor thumbnail generation.

src/library.rs

@@ -6,6 +6,8 @@ use std::path::PathBuf;
 use std::sync::Arc;
 
 use google_photoslibrary1 as photos;
+use image::imageops::FilterType;
+use image::ImageFormat;
 use log::error;
 use log::info;
 use log::warn;
@@ -16,7 +18,7 @@ use rocksdb::IteratorMode;
 use rocksdb::DB;
 
 // Used to ensure DB is invalidated after schema changes.
-const LIBRARY_GENERATION: &'static str = "2";
+const LIBRARY_GENERATION: &'static str = "5";
 
 #[derive(Clone)]
 pub struct Library {
@@ -143,14 +145,14 @@ impl Library {
     fn generational_key(generation: &str, key: &str) -> String {
         format!("{}/{}", generation, key)
     }
-    pub fn thumbnail(&self, media_items_id: &str, dimensions: (u32, u32)) -> Option<Vec<u8>> {
-        fn generate_thumbnail(
-            lib: &Library,
+    pub fn generate_thumbnail(
+        &self,
         media_items_id: &str,
         dimensions: (u32, u32),
+        filter: FilterType,
     ) -> Result<Vec<u8>, io::Error> {
         let (w, h) = dimensions;
-            match lib.original(&media_items_id) {
+        match self.original(&media_items_id) {
             None => {
                 warn!("Couldn't find original {}", &media_items_id);
                 Err(io::Error::new(
@@ -163,16 +165,15 @@ impl Library {
                     .with_guessed_format()?
                     .decode()
                     .map_err(|e| io::Error::new(io::ErrorKind::Other, e))?;
-                    // TODO (wathiede) resize..fill
-                    let img =
-                        orig_img.resize_to_fill(w, h, image::imageops::FilterType::CatmullRom);
+                let img = orig_img.resize_to_fill(w, h, filter);
                 let mut buf = Vec::new();
-                    img.write_to(&mut buf, image::ImageFormat::Jpeg)
+                img.write_to(&mut buf, ImageFormat::Jpeg)
                     .map_err(|e| io::Error::new(io::ErrorKind::Other, e))?;
                 Ok(buf)
             }
         }
     }
+    pub fn thumbnail(&self, media_items_id: &str, dimensions: (u32, u32)) -> Option<Vec<u8>> {
         fn cache_key(media_items_id: &str, dimensions: (u32, u32)) -> String {
             let (w, h) = dimensions;
             Library::generational_key(
@@ -191,7 +192,9 @@ impl Library {
             // Cache miss, fill cache and return.
             Ok(None) => {
                 info!("cache MISS {}", key);
-                let bytes = match generate_thumbnail(self, media_items_id, dimensions) {
+                let bytes =
+                    match self.generate_thumbnail(media_items_id, dimensions, FilterType::Lanczos3)
+                    {
                         Ok(bytes) => bytes,
                         Err(e) => {
                             error!("Failed to generate thumbnail for {}: {}", media_items_id, e);

src/web.rs

@@ -80,6 +80,7 @@ fn image(
     media_items_id: String,
     params: ImageParams,
 ) -> Result<impl warp::Reply, warp::Rejection> {
+    // TODO(wathiede): add caching headers.
     match lib.thumbnail(
         &media_items_id,
         (params.w.unwrap_or(0), params.h.unwrap_or(0)),