Update

Dockerfile

@@ -25,16 +25,20 @@ WORKDIR /var/www
 COPY . .
 COPY .env.example .env
 
-# Install dependencies
-RUN composer install --no-interaction --prefer-dist --optimize-autoloader
+# Set www-data user permission before running composer/install artisan
+RUN chown -R www-data:www-data /var/www
 
-# Generate app key
-RUN php artisan key:generate
+USER www-data
 
-# Set permissions
-RUN chown -R www-data:www-data /var/www \
-    && chmod -R 775 storage bootstrap/cache \
-    && chown -R www-data:www-data storage bootstrap/cache
+# Install dependencies & generate app key as www-data user
+RUN composer install --no-interaction --prefer-dist --optimize-autoloader \
+    && php artisan key:generate
+
+USER root
+
+# Set permissions again just in case
+RUN chown -R www-data:www-data /var/www/storage /var/www/bootstrap/cache \
+    && chmod -R 775 /var/www/storage /var/www/bootstrap/cache
 
 EXPOSE 9000
 CMD ["php-fpm"]