Make State-functons return Future-s

src/site.rs

@@ -77,27 +77,24 @@ struct WikiLookup {
 impl Lookup for WikiLookup {
     type Resource = ArticleResource;
     type Error = Box<::std::error::Error + Send + Sync>;
-    type Future = futures::future::FutureResult<Option<Self::Resource>, Self::Error>;
+    type Future = futures::BoxFuture<Option<Self::Resource>, Self::Error>;
 
     fn lookup(&self, path: &str, _query: Option<&str>, _fragment: Option<&str>) -> Self::Future {
         assert!(path.starts_with("/"));
 
         if path.starts_with("/_") {
             // Reserved namespace
-            return futures::finished(None);
+            return futures::finished(None).boxed();
         }
 
         let slug = &path[1..];
         if let Ok(article_id) = slug.parse() {
-            match self.state.get_article_revision_by_id(article_id) {
-                Ok(Some(article)) => {
-                    futures::finished(Some(ArticleResource::new(self.state.clone(), article)))
-                },
-                Ok(None) => futures::finished(None),
-                Err(err) => futures::failed(err),
-            }
+            let state = self.state.clone();
+            self.state.get_article_revision_by_id(article_id)
+                .and_then(|x| Ok(x.map(move |article| ArticleResource::new(state, article))))
+                .boxed()
         } else {
-            futures::finished(None)
+            futures::finished(None).boxed()
         }
     }
 }

src/state.rs

@@ -3,7 +3,7 @@ use std;
 use diesel;
 use diesel::sqlite::SqliteConnection;
 use diesel::prelude::*;
-use futures::{self, Future, IntoFuture};
+use futures::{Future, IntoFuture, BoxFuture};
 use r2d2::Pool;
 use r2d2_diesel::ConnectionManager;
 
@@ -21,7 +21,8 @@ impl State {
         State { connection_pool }
     }
 
-    pub fn get_article_revision_by_id(&self, article_id: i32) -> Result<Option<models::ArticleRevision>, Error> {
+    pub fn get_article_revision_by_id(&self, article_id: i32) -> BoxFuture<Option<models::ArticleRevision>, Error> {
+        (|| -> Result<_, _> {
             use schema::article_revisions;
 
             Ok(article_revisions::table
@@ -30,9 +31,10 @@ impl State {
                 .limit(1)
                 .load::<models::ArticleRevision>(&*self.connection_pool.get()?)?
                 .pop())
+        }()).into_future().boxed()
     }
 
-    pub fn update_article(&self, article_id: i32, base_revision: i32, body: String) -> futures::BoxFuture<models::ArticleRevision, Error> {
+    pub fn update_article(&self, article_id: i32, base_revision: i32, body: String) -> BoxFuture<models::ArticleRevision, Error> {
         self.connection_pool.get().into_future()
             .map_err(Into::into)
             .and_then(move |conn| {