DB migration - Solution #3

[Startrekzky]

To be added

[klesh]

The priority of this issue has been brought up, due to ee is planning to release with DevLake on next iteration.
@Startrekzky

[klesh]

Based on previous discussion, most of us tend to the following solution:

Solution #3: implement go-migrate functionality by using gorm.Migrator without go.AutoMigrate

How it works

has a migration_history that records all executed scripts

1. Write migration scripts in Golang
2. Register them all to framework
3. Framework executes unexecuted scripts one by one

Pros

1. Easy to implement on Framework level
2. Easy to understand

Cons

1. It's very tedious to write every single migration script and error-prone, like missing tables/columns and typos... We have 67 tables now, and there are more to come.
2. Migration script auto-generation becomes kind of mandatory in order to reduce error and work hours, but it's not an easy task.