Setup redis session driver

[azophy]

• setup redis container in docker-compose.yml
• configure redis as session driver in both Laravel & Codeigniter

Problem in Codeigniter

• CI version used by SIKD (3.1.8) has some bug regarding deprecated method in Predis. It should be upgraded to latest version.
  • reference: https://stackoverflow.com/a/71674977
  • Screenshot:
    

Possible problem regarding Laravel-Codeigniter shared session mechanism:

• both have different key format
• both have different serialization strategy (laravel use JSON, while CI use some other method. maybe using PHP's serialize() or session_decode() method)?

possible solution: use a custom third party session driver to achieve uniform redis session storage mechanism

chosen solution

change both session serialization settings to use PHP's serialize() method

[azophy]

https://github.com/bcit-ci/CodeIgniter/blob/45576ef6e62b5ff59da67f1697ee8c57809c7719/system/libraries/Session/Session.php#L114

sepertinya memang mengandalkan session mechanism dari PHP

[azophy]

driver itu nanti di wrap oleh https://github.com/bcit-ci/CodeIgniter/blob/3.1-stable/system/libraries/Session/OldSessionWrapper.php , yang akhirnya nanti dijadikan driver utk session handler bawaan PHP

[azophy]

class reference: https://codeigniter.com/userguide3/libraries/sessions.html#CI_Session

[azophy]

clue

• extend class CI_session untuk serialize menggunakan json. sayangnya minim dokumentasi: https://gist.github.com/755/3930711
• ada setting session.serialize_handler di php.ini

kayaknya memang format di redis CI itu pakai serialisasi dari session_encode(). referensi

[azophy]

Pencerahan: Laravel tidak memakai sistem session native dari PHP sama sekali :

https://github.com/laravel/framework/blob/9.x/src/Illuminate/Session/Middleware/StartSession.php#L112

berarti untuk serialisasinya perlu di utak atik lagi. kayaknya lebih gampang kalau codeigniter yang dibuat biar ngikut sistemnya Laravel

[azophy]

baca2 lagi, pilihan format serializer session PHP cuman ada 3 opsi:

• php_serialize : PHP serialize format
• php/php_binary : PHP internal formats
• wddx : WDDX are supported

kayaknya harus dirombak session handler nya CI biar pakai custom session class

[azophy]

open source library that mimics PHP's session_encode() serialization method: https://github.com/wikimedia/php-session-serializer

[azophy]

code snippet for emulating session_encode/decode serialization: https://stackoverflow.com/q/15538787

[azophy]

interesting info:

• ternyata serialisasi json di session laravel itu relatif baru. PR terkait: [9.x] JSON Session Option laravel/framework#40595
• ternyata ada undocumented config session.serialization untuk ganti metode serialisasi dari json jadi php. kalau bisa begitu, berarti setting session.serialize_handler di codeigniter juga bisa diganti jadi php_serialize biar keduanya cocok

worth trying