Going somewhere... but no idea where.

src/services/_users.rs

@@ -0,0 +1,52 @@
+use rusqlite::Connection;
+use serde::Deserialize;
+use serde::Serialize;
+
+use crate::db::external_id::UserId;
+use crate::db::users::{list_users, User};
+use crate::util::CustomResult;
+
+#[derive(Serialize, Debug)]
+pub struct Page<T> where T: Serialize {
+    total_number_of_page: usize,
+    current_page_number: usize,
+    content: Vec<T>,
+}
+
+impl<T> Page<T> where T: Serialize{
+    pub fn all_of(data: Vec<T>) -> Page<T>{
+        Page{
+            total_number_of_page: 0,
+            current_page_number: 10,
+            content: data
+        }
+    }
+}
+
+#[derive(Deserialize, Serialize, Debug)]
+pub struct UserDTO {
+    name: String,
+    id: String,  // todo: should be of type UserId
+}
+
+impl UserDTO {
+    fn from_entity(user: &User) -> UserDTO {
+        return UserDTO { name: user.get_name(), id: user.id().to_string() }
+    }
+}
+
+pub struct UserService<'a> {
+    conn: &'a Connection,
+}
+
+impl UserService<'_> {
+    pub fn new(conn: &Connection) -> UserService {
+        UserService { conn }
+    }
+
+    pub fn list_users(self) -> CustomResult<Page<UserDTO>> {
+        let users = list_users(self.conn)?.iter().map(UserDTO::from_entity).collect();
+        let ret = Page::all_of(users);
+        return Ok(ret)
+    }
+}