Implemented frontend external barcode lookup workflow + a plugin for Open Food Facts (closes #158)

data/plugins/OpenFoodFactsBarcodeLookupPlugin.php

@@ -0,0 +1,46 @@
+<?php
+
+use Grocy\Helpers\BaseBarcodeLookupPlugin;
+use GuzzleHttp\Client;
+
+/*
+	To use this plugin, configure it in data/config.php like this:
+	Setting('STOCK_BARCODE_LOOKUP_PLUGIN', 'OpenFoodFactsBarcodeLookupPlugin');
+*/
+
+class OpenFoodFactsBarcodeLookupPlugin extends BaseBarcodeLookupPlugin
+{
+	protected function ExecuteLookup($barcode)
+	{
+		$webClient = new Client(['http_errors' => false]);
+		$response = $webClient->request('GET', "https://world.openfoodfacts.net/api/v2/product/$barcode?fields=product_name,image_url");
+		$statusCode = $response->getStatusCode();
+
+		// Guzzle throws exceptions for connection errors, so nothing to do on that here
+
+		$data = json_decode($response->getBody());
+		if ($statusCode == 404 || $data->status != 1)
+		{
+			// Nothing found for the given barcode
+			return null;
+		}
+		else
+		{
+			$imageUrl = '';
+			if (isset($data->product->image_url) && !empty($data->product->image_url))
+			{
+				$imageUrl = $data->product->image_url;
+			}
+
+			return [
+				'name' => $data->product->product_name,
+				'location_id' => $this->Locations[0]->id,
+				'qu_id_purchase' => $this->QuantityUnits[0]->id,
+				'qu_id_stock' => $this->QuantityUnits[0]->id,
+				'qu_factor_purchase_to_stock' => 1,
+				'barcode' => $barcode,
+				'image_url' => $imageUrl
+			];
+		}
+	}
+}