Define a new Diesel Model for PodcastCover querries.

Define new Diesel Model and impl From<Podcast> trait,
Change the signature of downloader::cache_image function,
Change and merge hammond-gtk::utils::get_pixbuf_from_path functions.

hammond-data/src/dbqueries.rs

@@ -2,7 +2,7 @@
 
 use diesel::prelude::*;
 use diesel;
-use models::queryables::{Episode, EpisodeWidgetQuery, Podcast, Source};
+use models::queryables::{Episode, EpisodeWidgetQuery, Podcast, PodcastCoverQuery, Source};
 use chrono::prelude::*;
 use errors::*;
 
@@ -114,6 +114,17 @@ pub fn get_podcast_from_id(pid: i32) -> Result<Podcast> {
     Ok(podcast.filter(id.eq(pid)).get_result::<Podcast>(&*con)?)
 }
 
+pub fn get_podcast_cover_from_id(pid: i32) -> Result<PodcastCoverQuery> {
+    use schema::podcast::dsl::*;
+
+    let db = connection();
+    let con = db.get()?;
+    Ok(podcast
+        .select((id, title, image_uri))
+        .filter(id.eq(pid))
+        .get_result::<PodcastCoverQuery>(&*con)?)
+}
+
 pub fn get_pd_episodes(parent: &Podcast) -> Result<Vec<Episode>> {
     use schema::episode::dsl::*;
 

hammond-data/src/lib.rs

@@ -61,7 +61,7 @@ pub(crate) mod models;
 mod parser;
 mod schema;
 
-pub use models::queryables::{Episode, EpisodeWidgetQuery, Podcast, Source};
+pub use models::queryables::{Episode, EpisodeWidgetQuery, Podcast, PodcastCoverQuery, Source};
 
 /// [XDG Base Direcotory](https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html) Paths.
 #[allow(missing_debug_implementations)]

hammond-data/src/models/queryables.rs

@@ -427,6 +427,39 @@ impl Podcast {
     }
 }
 
+#[derive(Queryable, Debug, Clone)]
+/// Diesel Model of the podcast cover query.
+/// Used for fetching information about a Podcast's cover.
+pub struct PodcastCoverQuery {
+    id: i32,
+    title: String,
+    image_uri: Option<String>,
+}
+
+impl From<Podcast> for PodcastCoverQuery {
+    fn from(p: Podcast) -> PodcastCoverQuery {
+        PodcastCoverQuery {
+            id: *p.id(),
+            title: p.title,
+            image_uri: p.image_uri,
+        }
+    }
+}
+
+impl PodcastCoverQuery {
+    /// Get the Feed `title`.
+    pub fn title(&self) -> &str {
+        &self.title
+    }
+
+    /// Get the `image_uri`.
+    ///
+    /// Represents the uri(url usually) that the Feed cover image is located at.
+    pub fn image_uri(&self) -> Option<&str> {
+        self.image_uri.as_ref().map(|s| s.as_str())
+    }
+}
+
 #[derive(Queryable, Identifiable, AsChangeset, PartialEq)]
 #[table_name = "source"]
 #[changeset_options(treat_none_as_null = "true")]