Accessing postgres database with another microservice while testing phoenix app

Phoenix Forum Questions / Help
1

It’s kind of complicated question and possible something wrong with my own code but I almost gave up.
tldr: in dev version of phoenix app python microservice can fetch the row from postgres table, while in test – it can’t

In the Elixir app I have the test where i calling the :create method:

test "successfully add new review source", %{
   ...
 conn = Accounts.sign_in_user(conn, user)
 conn = post conn, review_source_path(conn, :create, review_source: %{
   ...
 })

the :create method:

def create(conn, %{"review_source" => review_source_params}) do
   ...
   changeset = ReviewSource.changeset(%ReviewSource{}, review_source_params)
   case Repo.insert(changeset) do
          {:ok, review_source} ->
          #test = Repo.get!(ReviewSource, review_source.id) this return not nil, so the object existing in database
          url = "mocroservice_url/#{review_source.id}"
          response = HTTPoison.patch!(url, "{}")

So in the HTTPoison.patch! line the microservice being called but it can’t get the object with such id:

20:39:50 web.1  | Review_SourcesDoesNotExist: <class '__main__.Review_Sources'> instance matching query does not exist:
20:39:50 web.1  | SQL: SELECT "t1"."id", "t1"."type", "t1"."url", "t1"."review_widget_id", "t1"."inserted_at", "t1"."updated_at" FROM "review_sources" AS "t1" WHERE ("t1"."id" = %s) LIMIT 1 OFFSET 0

In both elixir app and flask microservice while testing the databases name are identical – projname_test. The object id also identical but i also tried selecting all row from database in microservice route handler and it’s empty. It works correclty in dev when databases set to projname_dev, the dev version also works when databases set to projname_test.
So is there something i should know about database condition when testing?

2

So is there something i should know about database condition when testing?

Maybe that it happens inside a transaction and this transaction never gets committed. I think I had a similar problem recently, see Postgrex.Notifications process doesn't receive notifications in tests.

Try running your test inside Ecto.Adapters.SQL.Sandbox.unboxed_run/2:

test "successfully add new review source", %{conn: conn} do
  Ecto.Adapters.SQL.Sandbox.unboxed_run(YourApp.Repo, fn ->
    conn = Accounts.sign_in_user(conn, user)
    conn = post conn, review_source_path(conn, :create, review_source: %{
      # ...
    })
  end)
  # don't forget to clean up inserted data afterwards
end

This would actually commit the transaction, so your other service will see the inserted data.

3

I put all test code to Ecto.Adapters.SQL.Sandbox.unboxed_run and it works. But it seems it doesn’t clean the database then.

4

Yes, it doesn’t.

5

Yes, it doesn’t.

So what would be the workaround here?

6

The ecto.sandbox is built around the idea of testing against a long running transaction, but never commiting any data to the database. If you need to commit you data to the db you’d need to come up with different means of cleaning up the database / preventing async tests against the same data.

7

I delete the test data manually after the test has run.