Laravel unique validation on multiple columns

The following will work on the create

'data.ip' => ['required', 'unique:servers,ip,'.$this->id.',NULL,id,hostname,'.$request->input('hostname')]

and the following for the update

'data.ip' => ['required', 'unique:servers,ip,'.$this->id.','.$request->input('id').',id,hostname,'.$request->input('hostname')]

I'm presuming that id is your primary key in the table. Substitute it for your environment.

---

The (undocumented) format for the unique rule is:

table[,column[,ignore value[,ignore column[,where column,where value]...]]]

Multiple "where" conditions can be specified, but only equality can be checked. A closure (as in the accepted answer) is needed for any other comparisons.

You can use Rule::unique to achieve your validation rule

$messages = [
    'data.ip.unique' => 'Given ip and hostname are not unique',
];

Validator::make($data, [
    'data.ip' => [
        'required',
        Rule::unique('servers')->where(function ($query) use($ip,$hostname) {
            return $query->where('ip', $ip)
            ->where('hostname', $hostname);
        }),
    ],
],
$messages
);

edit: Fixed message assignation

Laravel 5.6 and above

Validation in the controller

The primary key (in my case) is a combination of two columns (name, guard_name)

I validate their uniqueness by using the Rule class both on create and on update method of my controller (PermissionsController)

---

PermissionsController.php

<?php

namespace App\Http\Controllers;

use App\Permission;

use Illuminate\Http\Request;
use Illuminate\Validation\Rule;
use App\Http\Controllers\Controller;

class PermissionsController extends Controller
{

    /**
     * Store a newly created resource in storage.
     */
    public function store(Request $request)
    {
        request()->validate([

            'name'        => 'required|max:255',

            'guard_name'  => [

                'required', 

                Rule::unique('permissions')->where(function ($query) use ($request) {

                    return $query
                        ->whereName($request->name)
                        ->whereGuardName($request->guard_name);
                }),
            ],
        ],
        [
            'guard_name.unique' => __('messages.permission.error.unique', [

                'name'              => $request->name, 
                'guard_name'        => $request->guard_name
            ]),
        ]);

        Permission::create($request->all());

        flash(__('messages.permission.flash.created'))->success();

        return redirect()->route('permission.index');
    }


    /**
     * Update the specified resource in storage.
     */
    public function update(Request $request, Permission $permission)
    {
        request()->validate([

            'name'        => 'required|max:255',

            'guard_name'  => [

                'required', 

                Rule::unique('permissions')->where(function ($query) use ($request, $permission) {

                    return $query
                        ->whereName($request->name)
                        ->whereGuardName($request->guard_name)
                        ->whereNotIn('id', [$permission->id]);
                }),
            ],
        ],
        [
            'guard_name.unique' => __('messages.permission.error.unique', [

                'name'              => $request->name, 
                'guard_name'        => $request->guard_name
            ]),
        ]);

        $permission->update($request->all());

        flash(__('messages.permission.flash.updated'))->success();

        return redirect()->route('permission.index');
    }
}

Notice in the update method i added an additional query constraint [ whereNotIn('id', [$permission->id]) ] to ignore the current model.

---

resources/lang/en/messages.php

<?php

return [

    'permission' => [

        'error' => [
            'unique' => 'The combination [":name", ":guard_name"] already exists',
        ],

        'flash' => [
            'updated' => '...',
            'created' => '...',
        ],
    ]
]

---

The flash() method is from the laracasts/flash package.