Automatic Schema Migrations

[lippserd]

Requirements

• Automatically apply pending migrations if a specific flag is given
• CLI (sub) command should be available to perform pending migrations
• Migrations might be optional
• Logging must be extensive
• It must be possible to programmatically hook into before/progress/finish migrations
• Support idempotent migrations (see https://github.com/Icinga/icingaweb2/blob/4472fe3ac2d5d7f559e5fc448b6dd266dccc118b/modules/monitoring/schema/migration-procedures.sql)
• Pending migrations should be visible in Web
• (Pending migrations should be started via Web, which triggers the migration in the respective component)