feat: add validators for username, email, password

* not passed yet

server/src/api/validators/authValidator.js

@@ -0,0 +1,43 @@
+import { query } from 'express-validator'
+
+import { isValidUsername } from '@linux-odyssey/utils'
+import { User } from '@linux-odyssey/models'
+
+export const checkUsername = () =>
+  query('username')
+    .notEmpty()
+    .isString()
+    .custom((username) => {
+      if (!isValidUsername(username)) {
+        throw new Error('Invalid username')
+      }
+      return true
+    })
+    .trim()
+
+export const checkNewUsername = () =>
+  checkUsername().custom(async (username) => {
+    if (await User.exists({ username })) {
+      throw new Error('Username taken')
+    }
+    return true
+  })
+
+export const checkEmail = () => query('email').notEmpty().isEmail().trim()
+
+export const checkNewEmail = () =>
+  checkEmail().custom(async (email) => {
+    if (await User.exists({ email })) {
+      throw new Error('Email taken')
+    }
+    return true
+  })
+
+export const checkPassword = () =>
+  query('password').notEmpty().isStrongPassword({
+    minLength: 8,
+    minNumbers: 1,
+    minLowercase: 1,
+    minUppercase: 1,
+    minSymbols: 0,
+  })