feat: added users command line.

src/users.rs

@@ -1,5 +1,28 @@
-use rusqlite::Connection;
+use rusqlite::{Connection, Result};
+use serde::{Serialize};
 
-fn create_user(conn: & Connection){
 
+#[derive(Debug, Serialize)]
+pub struct User {
+    id: i32,
+    name: String,
+    public_key: String,
+}
+
+pub fn create_user(conn: & Connection, name: &String, public_key: &String){
+    conn.execute("INSERT INTO users (name, public_key) VALUES (?1, ?2)",
+                 (name, public_key)).unwrap();
+}
+
+pub fn list_users(conn: & Connection) -> Result<Vec<Result<User>>>{
+
+    let mut stmt = conn.prepare("SELECT id, name, public_key FROM users")?;
+    let ret: Vec<Result<User>> = stmt.query_map([], |row| {
+        Ok(User {
+            id: row.get(0)?,
+            name: row.get(1)?,
+            public_key: row.get(2)?,
+        })
+    }).unwrap().collect();
+    return Ok(ret);
 }