Laravel HTTP Proxy Filesystem Adapter

HttpProxyAdapter.php

<?php

namespace App\Filesystem\Adapters;

use Illuminate\Support\Carbon;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Str;
use League\Flysystem\Config;
use League\Flysystem\FileAttributes;
use League\Flysystem\FilesystemAdapter;
use League\Flysystem\FilesystemException;

/**
 * Provides a http proxy filestore.
 */
class HttpProxyAdapter implements FilesystemAdapter
{
    private string $base;

    public function __construct(string $base)
    {
        if ( ! Str::startsWith($base, ['http://', 'https://'])) {
            throw new \Exception('Filesystem base must start with http:// or https://');
        }

        $this->base = Str::finish($base, '/');
    }

    public function fileExists(string $path): bool
    {
        return true;
    }
    
    public function directoryExists(string $path): bool
    {
        return true;
    }
    
    public function write(string $path, string $contents, Config $config): void
    {
        $this->throwUnsupportedException(__FUNCTION__);
    }
    
    public function writeStream(string $path, $contents, Config $config): void
    {
        $this->throwUnsupportedException(__FUNCTION__);
    }

    public function httpUrl(string $path): string
    {
        return $this->base . $path;
    }
    
    public function read(string $path): string
    {
        $response = Http::withOptions($this->httpOptions())->get($this->httpUrl($path));

        if ( ! $response->successful()) {
            return false;
        }

        return $response->body();
    }
    
    public function readStream(string $path)
    {
        $response = Http::withOptions($this->httpOptions(['stream' => true]))->get($this->httpUrl($path));

        return $response->getBody()->detach();
    }
    
    public function delete(string $path): void
    {
        $this->throwUnsupportedException(__FUNCTION__);
    }
    
    public function deleteDirectory(string $path): void
    {
        $this->throwUnsupportedException(__FUNCTION__);
    }
    
    public function createDirectory(string $path, Config $config): void
    {
        $this->throwUnsupportedException(__FUNCTION__);
    }
    
    public function setVisibility(string $path, string $visibility): void
    {
        $this->throwUnsupportedException(__FUNCTION__);
    }
    
    public function visibility(string $path): FileAttributes
    {
        return $this->getFileAttributes($path);
    }
    
    public function mimeType(string $path): FileAttributes
    {
        return $this->getFileAttributes($path);
    }
    
    public function lastModified(string $path): FileAttributes
    {
        return $this->getFileAttributes($path);
    }
    
    public function fileSize(string $path): FileAttributes
    {
        return $this->getFileAttributes($path);
    }
    
    public function listContents(string $path, bool $deep): iterable
    {
        return [];
    }
    
    public function move(string $source, string $destination, Config $config): void
    {
        $this->throwUnsupportedException(__FUNCTION__);
    }
    
    public function copy(string $source, string $destination, Config $config): void
    {
        $this->throwUnsupportedException(__FUNCTION__);
    }

    private function throwUnsupportedException($function)
    {
        throw new FilesystemException("Not possible to {$function} using this driver.");
    }

    private function httpOptions(array $options = []): array
    {
        return array_merge(
            ['verify' => false],
            $options
        );
    }

    private function getFileAttributes(string $path)
    {
        $response = Http::withOptions($this->httpOptions())->head($this->httpUrl($path));
        
        if ( ! $response->ok()) {
            throw new FilesystemException("Unable to find file at: {$path}.");
        }

        return new FileAttributes(
            $path,
            $response->header('Content-Length') ?: 0,
            null,
            $response->header('Last-Modified') ? Carbon::parse($response->header('Last-Modified'))->getTimestamp() : null,
            $response->header('Content-Type'),
        );
    }
}