Add publish option that does not affect publish status while migrating everything

[hpohlmeyer]

The scenario

There are two cases where you might want to run a migration:

1. Batch updating lots of data without changing the shape of a story
2. Adjusting the shape of a story to react to component changes

This is about the second option. Let's say you have a component that looks like this:

type MyComponent = {
  name: string;
};

and you want to migrate to something like this:

type MyComponent = {
  firstName: string;
  lastName: string;
};

And then there are three stories that would be affected by the migration

1. A story with draft status
2. A story with published-with-changes status
3. A story with published status

From a dev perspective I would assume I can run the migrations and delete all legacy code that handles the name property, since only firstName and lastName are used from now on.

From a content-editor perspective I do not want my status to change at all, because it is an internal migration that does not change the content.

The current state

Since it is not quite clear from the docs how every status affects the results, I ran some tests and these are the outcomes (v4.10.0):

without flag

	draft	changed	published
status	draft	changed	changed
draft json	migrated	migrated	migrated
prod json	404	untouched	untouched

--publish=all

	draft	changed	published
status	published	published	published
draft json	migrated	migrated	migrated
prod json	migrated	migrated	migrated

--publish=published

	draft	changed	published
status	draft	changed	published
draft json	migrated	migrated	migrated
prod json	404	untouched	migrated

--publish=published-with-changes

	draft	changed	published
status	draft	published	changed
draft json	migrated	migrated	migrated
prod json	404	migrated	untouched

The problem

The published option keeps every status as-is, so that matches what I want as a content-editor, but it does not migrate the published values for stories which are currently published-with-changes. That is a problem, because when I remove the code that handles the name property, my site will break in prod.

Possible solution

For this case, another option that works like this would work:

	draft	changed	published
status	draft	changed	published
draft json	migrated	migrated	migrated
prod json	404	migrated	migrated

By doing that as a developer, I don't mess with the content-editor's publish states, and I can safely remove the code, that handles the name property.

Another option could be to split the publish flag into multiple dedicated flags, that control the status migration, the draft json migration and the production json separately. Although to mimic the current behavior this would get quite complex, because you'd also need to control the migration behavior per publish status.

---

I have tried to implement that myself, but the update story endpoint from the management api used under the hood does not let me decouple the update from the status either if I am not missing something. I would be happy for any hints on how this could be implemented.