Add ActivityPubFetchService for signed GET requests

app/Services/ActivityPubFetchService.php

@@ -0,0 +1,59 @@
+<?php
+
+namespace App\Services;
+
+use Zttp\Zttp;
+use App\Profile;
+use App\Util\ActivityPub\Helpers;
+use App\Util\ActivityPub\HttpSignature;
+
+class ActivityPubFetchService
+{
+	public $signed = true;
+	public $actor;
+	public $url;
+	public $headers = [
+		'Accept'		=> 'application/activity+json, application/json',
+		'User-Agent'	=> 'PixelfedBot - https://pixelfed.org'
+	];
+
+	public static function queue()
+	{
+		return new self;
+	}
+
+	public function signed($signed = true)
+	{
+		$this->signed = $signed;
+		return $this;
+	}
+
+	public function actor($profile)
+	{
+		$this->actor = $profile;
+		return $this;
+	}
+
+	public function url($url)
+	{
+		if(!Helpers::validateUrl($url)) {
+			throw new \Exception('Invalid URL');
+		}
+		$this->url = $url;
+		return $this;
+	}
+
+	public function get()
+	{
+		if($this->signed == true && $this->actor == null) {
+			throw new \Exception('Cannot sign request without actor');
+		}
+		return $this->signedRequest();
+	}
+
+	protected function signedRequest()
+	{
+		$this->headers = HttpSignature::sign($this->actor, $this->url, false, $this->headers);
+		return Zttp::withHeaders($this->headers)->get($this->url)->body();
+	}
+}