Error running make:request on laravel 5 - laravel

Question

When running the example code on the laravel docs php artisan make:request StoreBlogPostRequest to create a new validation controller, I get the following error
[RuntimeException]
Unable to detect application namespace.
I'm not sure what's wrong, I've done some searching, but nothing really explains this error. Any ideas?

Answer 1

In Laravel 5, an "application" is a collection of PHP files under a single namespace, stored in the folder app/
By default, and in most of the Laravel 5 sample code from the docs, this namespace is App\. For example, one controller in your application might look like this.
namespace App\Http\Controller;
class MyController
{
//...
}
When Laravel generates code (i.e. when you use the make:request command), it needs to know what this application namespace is (it's possible to change the namespace with the artisan app:name command). For some reason, in your system, Laravel 5 can't detect the namespace.
If you look at the section of Laravel 5 core code that detects the namespace
#File: vendor/laravel/framework/src/Illuminate/Console/AppNamespaceDetectorTrait.php
protected function getAppNamespace()
{
$composer = json_decode(file_get_contents(base_path().'/composer.json'), true);
foreach ((array) data_get($composer, 'autoload.psr-4') as $namespace => $path)
{
foreach ((array) $path as $pathChoice)
{
if (realpath(app_path()) == realpath(base_path().'/'.$pathChoice)) return $namespace;
}
}
throw new RuntimeException("Unable to detect application namespace.");
}
You'll see that Laravel detects the namespace by looking at your composer.json file, and looking for thefirst valid psr-4 namespace.
My guess is your composer.json file is missing the namespace
"autoload": {
"classmap": [
"database"
],
"psr-4": {
"App\\": "app/"
}
},
Add that back in, and you'll be good to go.

Answer 2

Usually, this error can be mapped to syntax issues or errors in composer.json file. Check for any trailing commas or Auto load issue. For e.g.
"require-dev": {
"barryvdh/laravel-debugbar": "^3.5",
"phpunit/phpunit": "^7.5",
},
This should be..
"require-dev": {
"barryvdh/laravel-debugbar": "^3.5",
"phpunit/phpunit": "^7.5"
},
See no trailing commas at the end of "phpunit/phpunit": "^7.5"