update rocket and add diesel

src/task.rs

@@ -0,0 +1,34 @@
+use rocket::serde::Serialize;
+use diesel::{self, result::QueryResult, Queryable, Insertable, prelude::*};
+
+mod schema {
+    table! {
+        tasks {
+            id -> Nullable<Integer>,
+            description -> Text,
+            completed -> Bool,
+        }
+    }
+}
+
+use schema::tasks;
+use schema::tasks::dsl::{tasks as all_tasks, completed as task_completed};
+
+use crate::DbConn;
+
+#[derive(Serialize, Queryable, Insertable, Debug, Clone)]
+#[serde(crate = "rocket::serde")]
+#[table_name="tasks"]
+pub struct Task {
+    pub id: Option<i32>,
+    pub description: String,
+    pub completed: bool
+}
+
+impl Task {
+    pub async fn all(conn: &DbConn) -> QueryResult<Vec<Task>> {
+        conn.run(|c| {
+            all_tasks.order(tasks::id.desc()).load::<Task>(c)
+        }).await
+    }
+}