update: add docs

- README: init password
- add docs support to database interface

README.md

@@ -95,6 +95,12 @@ execute `docker compose up --detach`.
 
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+## Password initialization
+
+When the application initializes the database for the first time, it sets up an admin user with a default password : `admin`. You have the option to set your own password instead using either the `PASSWORD` environment variable or the `PASSWORD_HASH` environment variable. Follow [this link](./How_to_generate_an_bcrypt_hash.md) to generate a bcrypt hash password.
+
+The `PASSWORD` environment variable is plain text and will be hashed at runtime by wg-easy. On the other hand, the `PASSWORD_HASH` environment variable is already hashed.
+
 ## Options
 
 These options can be configured by setting environment variables using `-e KEY="VALUE"` in the `docker run` command.

src/lib/database/AbstractDatabase.js

@@ -10,14 +10,37 @@ module.exports = class DatabaseInterface {
     }
   }
 
+  /**
+   * Initializes the database if does not exist
+   *
+   * @returns {Promise<void>}
+   * @throws {ServerError} If not implemented by the subclass
+   */
   async initDb() {
     throw new ServerError('You must implement this function');
   }
 
+  /**
+   * Compares the provided password with the stored password for the given username
+   *
+   * @param {string} username - The username of the user
+   * @param {string} password - The password to compare
+   * @returns {Promise<boolean>} - Return `true` if the password matches, otherwise `false`
+   * @throws {ServerError} If not implemented by the subclass
+   */
   async comparePassword(username, password) {
     throw new ServerError('You must implement this function');
   }
 
+  /**
+   * Updates the password for the given user
+   *
+   * @param {string} username - The username of the user
+   * @param {string} oldPassword - The current password of the user
+   * @param {string} newPassword - The new password to set
+   * @returns {Promise<void>}
+   * @throws {ServerError} If not implemented by the subclass
+   */
   async updatePassword(username, oldPassword, newPassword) {
     throw new ServerError('You must implement this function');
   }