allow setting configuration by environment variables, fixes #3560

Closes #3560

Merge request studip/studip!2875

3 files changed, 25 insertions, 4 deletions

diff --git a/lib/bootstrap-autoload.php b/lib/bootstrap-autoload.php
index 3a767c1..eb9ac12 100644
--- a/lib/bootstrap-autoload.php
+++ b/lib/bootstrap-autoload.php
@@ -1,7 +1,4 @@
 <?php
-// Include composer's autoload
-require __DIR__ . '/../composer/autoload.php';
-
 // Setup autoloading
 require 'lib/classes/StudipAutoloader.php';
 StudipAutoloader::register();
diff --git a/lib/bootstrap.php b/lib/bootstrap.php
index 06ddca5..364f9d9 100644
--- a/lib/bootstrap.php
+++ b/lib/bootstrap.php
@@ -9,8 +9,16 @@
  * the License, or (at your option) any later version.
  */
 
+// Include composer's autoload
+require __DIR__ . '/../composer/autoload.php';
+
+// Load enviroment
+$dot_env_path = __DIR__ . '/..';
+$dotenv = \Dotenv\Dotenv::createImmutable($dot_env_path);
+$dotenv->safeLoad();
+
 // Default environment, do not change. Change in config/config_local.inc.php.
-const DEFAULT_ENV = 'production';
+define('DEFAULT_ENV',  $_ENV['STUDIP_ENV'] ?? 'production');
 
 //software version - please leave it as it is!
 $SOFTWARE_VERSION = '6.0.alpha';
diff --git a/lib/classes/Config.class.php b/lib/classes/Config.class.php
index 2f6b728..642665d 100644
--- a/lib/classes/Config.class.php
+++ b/lib/classes/Config.class.php
@@ -127,9 +127,14 @@ class Config implements ArrayAccess, Countable, IteratorAggregate
      */
     public function getValue($field)
     {
+        if ($this->fromEnv($field)) {
+            return $_ENV["STUDIP_CONFIG_{$field}"];
+        }
+
         if (array_key_exists($field, $this->data)) {
             return $this->data[$field];
         }
+
         if (isset($GLOBALS[$field]) && !isset($_REQUEST[$field])) {
             return $GLOBALS[$field];
         }
@@ -450,4 +455,15 @@ class Config implements ArrayAccess, Countable, IteratorAggregate
 
         return (string) $value;
     }
+
+    /**
+     * Returns whether the value was set from the environment.
+     *
+     * @param string $field
+     * @return bool
+     */
+    public function fromEnv(string $field): bool
+    {
+        return isset($_ENV["STUDIP_CONFIG_{$field}"]);
+    }
 }