By default, rails makes timestamp columns (`created_at` and
`updated_at`) non-nullable, we also have some required core and plugins
columns we wouldn't necessarily want to enforce in the intermediate DB
schema. It'll be better to set the default values for these during
import instead of enforcing these at the converter level.
This change adds support for globally modifying a column’s `nullable`
state, defaulting all `created_at` columns to be `nullable` while
allowing for table level overrides.
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Co-authored-by: Gerhard Schlager <gerhard.schlager@discourse.org>
* Splits the existing script into multiple classes
* Adds command for generating IntermediateDB schema (`migrations/bin/cli schema generate`)
* Changes the syntax of the IntermediateDB schema config
* Adds validation for the schema config
* It uses YAML schema aka JSON schema to validate the config file
* It generates the SQL schema file and Ruby classes for storing data in the IntermediateDB
