From ee2fadb7998f624284eaceb638200d66c44e5038 Mon Sep 17 00:00:00 2001
From: Stefan Haller <fgrsnau@gmail.com>
Date: Fri, 31 Jul 2020 19:59:39 +0200
Subject: [PATCH] Run multi instances by making GROCY_DATAPATH customizable

Previously the data directory was fixed to the GROCY_DATAPATH constant.

This commit allows overriding the default GROCY_DATAPATH location by the
FastCGI parameter `GROCY_DATAPATH`. Relative paths are modified and get
rooted at the top level grocy installation directory.

The previous behaviour is preserved in case the new parameter is absent.

The following example nginx config snippet shows how to run multiple
instances.

```nginx
server {
    location /instance1/ {
        alias /var/www/grocy/;
        set $instance instance1;
        try_files $uri @grocy;
    }

    location /instane2/ {
        alias /var/www/grocy/;
        set $instance instance2;
        try_files $uri @grocy;
    }

    location @grocy {
        fastcgi_pass 127.0.0.1:9000;
        include fastcgi_params;
        fastcgi_param SCRIPT_FILENAME index.php;
        fastcgi_param GROCY_DATAPATH data/$instance;
    }
}
```
---
 public/index.php | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/public/index.php b/public/index.php
index 4d7356ce..55eef364 100644
--- a/public/index.php
+++ b/public/index.php
@@ -10,7 +10,22 @@ if (file_exists(__DIR__ . '/../embedded.txt'))
 else
 {
 	define('GROCY_IS_EMBEDDED_INSTALL', false);
-	define('GROCY_DATAPATH', __DIR__ . '/../data');
+
+	$datapath = 'data';
+	if (getenv('GROCY_DATAPATH') !== false)
+	{
+		$datapath = getenv('GROCY_DATAPATH');
+	}
+	elseif (array_key_exists('GROCY_DATAPATH', $_SERVER))
+	{
+		$datapath = $_SERVER['GROCY_DATAPATH'];
+	}
+
+	if ($datapath[0] != '/')
+	{
+		$datapath = __DIR__ . '/../' . $datapath;
+	}
+	define('GROCY_DATAPATH', $datapath);
 }
 
 require_once __DIR__ . '/../helpers/PrerequisiteChecker.php';