Laravel JWT Auth Attempts Returns False Always: Debugging Custom User Implementations

Hope you are doing well.

As a senior developer, I've seen countless instances where authentication flows seem perfectly fine on paper but fail spectacularly in practice. The scenario you are describing—where your login attempts return an unauthorized response despite correct credentials—is extremely common when customizing Laravel’s built-in authentication systems, especially when dealing with non-standard table structures or custom hashing methods.

This post will dive deep into why your JWT authentication might be failing and provide a comprehensive solution based on the code snippets you provided. We will look at the intersection of Eloquent models, the Laravel Passport/JWT package behavior, and database constraints.

Diagnosing the Authentication Failure

The failure stems not necessarily from the JWT mechanism itself, but from how the auth() helper within the framework attempts to locate a valid user record based on the credentials you provide in the $creds array.

In your setup, the critical points of friction are:

1. Custom Identifier: You are using email_id instead of the default Eloquent primary key (id) for identification.
2. Password Hashing Inconsistency: Relying on manual MD5 hashing bypasses Laravel’s secure password handling mechanisms, which can cause issues during authentication checks if not configured correctly within the provider.
3. JWT Provider Setup: The JWT package relies heavily on the standard Eloquent user provider to fetch and validate the user before issuing a token.

When auth()->attempt($creds) executes, it queries the database based on the credentials. If your custom setup doesn't align perfectly with what Laravel expects for model identification or password verification, the attempt fails silently, resulting in an unauthorized response (HTTP 401).

Solution 1: Aligning Custom Models with Laravel Standards

The most robust solution is to ensure your custom user model adheres to Laravel’s expectations, especially regarding how it identifies the user and handles credentials. While you can use custom fields, for seamless integration with default authentication guards like jwt, sticking closer to standard Eloquent practices often prevents these kinds of runtime errors.

Refactoring the User Model

In your `App\Model