Migrations are applied incorrectly in all repos

Ash Forum Ash Questions / Help
,
1

In my system I’m adding a second repo to connect. To do that I did the following changes:

config/config.exs

config :marketplace, Marketplace.ApRepo,
  username: "postgres",
  password: "postgres",
  hostname: "localhost",
  database: "ap_dev",
  port: 5432,
  show_sensitive_data_on_connection_error: true,
  pool_size: 10

lib/ap_repo.ex

defmodule Marketplace.ApRepo do
  use AshPostgres.Repo, otp_app: :marketplace
end

lib/application.ex

defmodule Marketplace.Application do
  def start(_, _) do
    children = [
      ...
      ApRepo
    ]
    ...
  end
end

Then I added one resource to it and generated the migration.

A new migration file was correctly added to the priv/ap_repo/migrations directory.

But, when I ran the mix ash_postgres.migrate, the migration process applied all the migrations I have in my original Repo to the ApRepo and not only that new resource I created.

I did notice this warning from the documentation:

This is only really useful if your api or apis only use a single repo. If you
have multiple repos and you want to run a single migration and/or migrate/roll
them back to different points, you will need to use the ecto specific task, mix
ecto.migrate and provide your repo name.

So, does this means that I need to start using ecto.migrate from now on or only if more than one repo uses the same api?

2

:thinking: that sounds like a bug. You should be able to use that task with multiple repos, the main drawback is if you want to only migrate a specific repo. We can probably make our task support a --repo option if it doesn’t already.

So yeah if we’re actually applying migrations from both repos to one repo that is a bug somewhere. An example project showing this happening would be really useful. I’ve had multiple repos set up in an application and not seen that issue before.

3

Took me some time, but here is a small project that triggers the bug GitHub - sezaru/test_ash_multi_repo

Basically it has 3 resources, resource 1 and 2 uses repo 1, resource 3 uses repo 2.

If you run mix reset Ash will generate the 3 resources in both DBs.

1 Like
4

Just a small bump, @zachdaniel were you able to reproduce the bug with the above example project?

5

Honestly, this completely fell of my radar :frowning: sorry about that. Can you open an issue for this on ash_postgres? I will look into it soon

6

done Migrations are applied incorrectly with multiple repos · Issue #197 · ash-project/ash_postgres · GitHub

7

Fixed in AshPostgres main branch.

1 Like
8

I had the same issue and after your fix migrate is working fine. However I tried to rollback and it applied for both my database

I used:
mix ash_postgres.rollback -n 1

I expected it to rollback the last migrate, but it applied the last rollback of each of my databases

Specifying it this way:
mix ecto.rollback --migrations-path <path> -r <Repo> -n 1
works fine

Any idea?

9

You would want to mix ash_postgres.rollback -n 1 -r TheOnlyRepo. mix ash_postgres.rollback -n 1 couldn’t know which repo you want to do by default.

1 Like