Loading path /import/wallabag-v2 gives 500 Internal Server Error

[Strubbl]

Issue details

When i want to open the page where I can import my v2 json backup, i get an error:

Oops! An Error Occurred The server returned a "500 Internal Server Error". Something is broken. Please let us know what you were doing when this error occurred. We will fix it as soon as possible. Sorry for any inconvenience caused.

The apache error log has no information about this error.

But the var/log within the wallabag folder has the following message on calling the import page:

[2016-04-06 23:47:59] request.INFO: Matched route "import_wallabag_v2". {"route_parameters":{"_controller":"Wallabag\\ImportBundle\\Controller\\WallabagV2Controller::indexAction","_route":"import_wallabag_v2"},"request_uri":"https://wallabag.linux4tw.de/import/wallabag-v2"} []
[2016-04-06 23:47:59] security.DEBUG: Read existing security token from the session. {"key":"_security_secured_area"} []
[2016-04-06 23:47:59] security.DEBUG: User was reloaded from a user provider. {"username":"strubbl","provider":"Symfony\\Bridge\\Doctrine\\Security\\User\\EntityUserProvider"} []
[2016-04-06 23:48:00] request.CRITICAL: Uncaught PHP Exception Twig_Error_Runtime: "An exception has been thrown during the rendering of a template ("Unable to create the cache directory (/home/strubbl/git/wallabag/var/cache/prod/twig/7c).") in "WallabagCoreBundle:themes/material/Entry:new_form.html.twig" at line 2." at /home/strubbl/git/wallabag/var/cache/prod/classes.php line 1242 {"exception":"[object] (Twig_Error_Runtime(code: 0): An exception has been thrown during the rendering of a template (\"Unable to create the cache directory (/home/strubbl/git/wallabag/var/cache/prod/twig/7c).\") in \"WallabagCoreBundle:themes/material/Entry:new_form.html.twig\" at line 2. at /home/strubbl/git/wallabag/var/cache/prod/classes.php:1242, RuntimeException(code: 0): Unable to create the cache directory (/home/strubbl/git/wallabag/var/cache/prod/twig/7c). at /home/strubbl/git/wallabag/vendor/twig/twig/lib/Twig/Cache/Filesystem.php:60)"} []
[2016-04-06 23:48:00] request.CRITICAL: Uncaught PHP Exception Twig_Error_Runtime: "An exception has been thrown during the rendering of a template ("Unable to create the cache directory (/home/strubbl/git/wallabag/var/cache/prod/twig/7c).") in "WallabagImportBundle:WallabagV1:index.html.twig" at line 14." at /home/strubbl/git/wallabag/var/cache/prod/classes.php line 1138 {"exception":"[object] (Twig_Error_Runtime(code: 0): An exception has been thrown during the rendering of a template (\"Unable to create the cache directory (/home/strubbl/git/wallabag/var/cache/prod/twig/7c).\") in \"WallabagImportBundle:WallabagV1:index.html.twig\" at line 14. at /home/strubbl/git/wallabag/var/cache/prod/classes.php:1138, RuntimeException(code: 0): Unable to create the cache directory (/home/strubbl/git/wallabag/var/cache/prod/twig/7c). at /home/strubbl/git/wallabag/vendor/twig/twig/lib/Twig/Cache/Filesystem.php:60)"} []
[2016-04-06 23:48:00] security.DEBUG: Stored the security token in the session. {"key":"_security_secured_area"} []

Environment

• wallabag version (or git revision) that exhibits the issue: 2.0.0
• How did you install wallabag? Via composer create-project
• Last wallabag version that did not exhibit the issue (if applicable):
• php version: PHP 5.6.17-0+deb8u1
• OS:Debian GNU/Linux 8
• type of hosting (shared or dedicated): dedicated
• which storage system you choose at install (SQLite, MySQL/MariaDB or PostgreSQL): mysql

Steps to reproduce/test case

• fresh install of wallabg
• login to wallabag
• click on "Import"
• click on "Import Contents" in the wallabag v2 area (clicking on any other area, v1 or pocket results in the same error)
• get the error

[Strubbl]

Oh, okay, it is because of the wrong folder permissions of wallabag/var/cache. Apache should be able to write there. Ooops. Sorry for the issue noise. I am closing this one cause with fixing the access rights the error is gone.