Fix for Dotenv 1.1.1 and Laravel 5.1.7 issues with concurrent requests failing because of PHP threaded getenv/putenv implementation. This fix does not work for Laravel 5.2, see https://gist.github.com/progmars/5c18235360c04b621ed7 for the L5.2 fix.

dotenv_1_1_1_concurrent_fix_vendor.patch

Fix for Dotenv and Laravel issues with concurrent requests failing because of PHP threaded getenv/putenv implementation.

diff --git a/vendor/laravel/framework/src/Illuminate/Foundation/helpers.php b/vendor/laravel/framework/src/Illuminate/Foundation/helpers.php
index de5939e..715673d 100644
--- a/vendor/laravel/framework/src/Illuminate/Foundation/helpers.php
+++ b/vendor/laravel/framework/src/Illuminate/Foundation/helpers.php
@@ -625,10 +625,15 @@ if (!function_exists('env'))
      */
     function env($key, $default = null)
     {
-        $value = getenv($key);
-
-        if ($value === false) {
-            return value($default);
-        }
+        // workaround for
+        // https://github.com/laravel/framework/pull/8187
+        // and
+        // https://github.com/vlucas/phpdotenv/issues/76
+        $value = Dotenv::findEnvironmentVariable($key);
+
+        // false to null for findEnvironmentVariable() result check
+        if ($value === null) {
+            return value($default);
+        }
 
         switch (strtolower($value)) {
diff --git a/vendor/vlucas/phpdotenv/src/Dotenv.php b/vendor/vlucas/phpdotenv/src/Dotenv.php
index f91c848..4f377c4 100644
--- a/vendor/vlucas/phpdotenv/src/Dotenv.php
+++ b/vendor/vlucas/phpdotenv/src/Dotenv.php
@@ -13,7 +13,8 @@ class Dotenv
      * @var bool
      */
     protected static $immutable = true;
-
+    protected static $cache = [];
+
     /**
      * Load `.env` file in given directory.
      *
@@ -77,12 +78,30 @@ class Dotenv
     {
         list($name, $value) = static::normaliseEnvironmentVariable($name, $value);
 
+        // workaround for
+        // https://github.com/laravel/framework/pull/8187
+        // and
+        // https://github.com/vlucas/phpdotenv/issues/76
+
+        // don't rely upon findEnvironmentVariable because there might be situations
+        // when getenv() or $_ENV is set, but $cached[$name] is not,
+        // and then for later requests getenv() and $_ENV are both empty and also no value in cache,
+        // therefore this additional fix is here to ensure that we always cache the value
+
+        // but first keep the value while we haven't updated the cache because after that the value will be returned from the cache
+        // thus completely ignoring ENV, which is not what we intended
+        $oldVal = static::findEnvironmentVariable($name);
+
+        if (static::$immutable === false || !array_key_exists($name, static::$cache)){
+            static::$cache[$name] = $value;
+        }
+
         // Don't overwrite existing environment variables if we're immutable
         // Ruby's dotenv does this with `ENV[key] ||= value`.
-        if (static::$immutable === true && !is_null(static::findEnvironmentVariable($name))) {
+        if (static::$immutable === true && !is_null($oldVal)) {
             return;
         }
-
+
         putenv("$name=$value");
         $_ENV[$name] = $value;
         $_SERVER[$name] = $value;
@@ -263,5 +282,11 @@ class Dotenv
                 return $_ENV[$name];
             case array_key_exists($name, $_SERVER):
                 return $_SERVER[$name];
+            // workaround for
+            // https://github.com/laravel/framework/pull/8187
+            // and
+            // https://github.com/vlucas/phpdotenv/issues/76
+            case array_key_exists($name, static::$cache):
+                return static::$cache[$name];
             default:
                 $value = getenv($name);