Demo of LiveAdmin's MultiRepo Capabilities

• LiveAdmin supports multiple repos out of the box because Ecto.Repo supports multiple repos out of the box.
  • See this issue for a description.
• This git repository has 2 apps: AppB which contains a simple User schema and AppA which contains schemas for Role and UserRoleMapping.
• We are using SQLite3 here for simplicity but this works with PostgreSQL too.
• AppA depends on AppB to implement UserRoleMapping. To achieve this, we are going to configure the 2 apps to use the same DB file.
  • Not really relevant to this demo but we are going to prevent AppB from starting its endpoint when run in AppA's supervision tree.
• We will install and configure live_admin in AppA to access schemas from both apps.
• Each step is documented as a commit so use the commits to follow along.

Steps

_NB - cd and similar commands skipped for brevity.`

mix phx.new app_b --database sqlite3
mix phx.gen.json Accounts User users name email
mix phx.new app_a --database sqlite3
# In AppA
mix phx.gen.json Admin Role roles name
mix phx.gen.json Admin UserRoleMapping user_role_mappings user_id:references:users role_id:references:roles
# At this point, the migration will fail because AppA doesn't know about `users` yet.
# Add `:app_b` as dependency and make changes to `config.exs` and `dev.exs` to link the repos and make both use the same DB file.
# Configure AppB so that it doesn't start its endpoint when run in AppA's supervision tree.