John Davidson

Message:

For my app, I would like to offer my users a choice between file-based and database-driven sessions. I usually use file-based sessions, but over time more users are asking for database-based for a whole host of reasons (mainly file system restrictions on random hosting sites).

However, I'm concerned regarding data persistence. It would be great if there was a straightforward way to convert between the two while preserving user data.

Does CI3 have that function? If not, how can I do that?

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My Answer:
Unfortunately, CodeIgniter 3 does not have a built-in function to convert between file-based and database-driven sessions while preserving user data. However, you can achieve this by writing custom code to migrate the session data from one storage method to another.

Here is a general outline of how you can approach this task:

1. Create a new database table to store session data if you haven't already done so. You can use the following SQL query to create a basic session table:

sql
CREATE TABLE ci_sessions (
id VARCHAR(128) NOT NULL,
ip_address VARCHAR(45) NOT NULL,
timestamp INT(10) UNSIGNED DEFAULT 0 NOT NULL,
data TEXT DEFAULT '' NOT NULL
);


2. Write a script that reads the session data from the file-based storage (e.g., `application/cache`) and inserts it into the database table you created in step 1. You can use CodeIgniter's File Helper to read the session files and PHP's `serialize()` and `unserialize()` functions to handle the data serialization.

3. Update your CodeIgniter configuration to use the database-driven session storage. You can do this by setting the `sess_driver` configuration option to `'database'` and configuring the database connection settings for sessions in the `database.php` configuration file.

4. Test the migration script to ensure that the session data is successfully transferred from the file-based storage to the database-driven storage.

5. Once you have verified that the migration script works correctly, you can safely switch your application to use the database-driven session storage.

Keep in mind that this process may require some manual intervention and testing to ensure that all session data is migrated correctly. It is also recommended to backup your session data before performing the migration to avoid any data loss.