Static shared connection following old example doesn't work nicely with tests.

[leuchthelp]

Hey there, proper channel this time.

I've found this older guide from the cookbook on how to establish a single static connection, which can be shared.

I'm having a little issue with 2 of my current test. Both are setup as:

#[tokio::test]
#[ignore]
#[serial]
async fn some_test {
  init_db().await.unwrap();
  //...
}

Where both have to perform functions that can only be setup once & therefore have to run in serial. For this I use the serial_test crate.

The connection is setup as follows:

use anyhow::Result;
use sea_orm::*;
use tokio::sync::OnceCell;

pub static DB_CLIENT: OnceCell<DatabaseConnection> = OnceCell::const_new();

pub async fn init_db() -> Result<()> {
    if DB_CLIENT.initialized() {
        return Ok(());
    }

    let db = Database::connect("sqlite::memory:").await?;

    db.get_schema_registry("journey-db::entity::*")
        .sync(&db)
        .await?;

    DB_CLIENT.set(db)?;
    Ok(())
}

pub fn get_conn() -> &'static DatabaseConnection {
    return DB_CLIENT.get().unwrap();
}

Each test calls the init_db() function once, since I can really control the order of serial execution, only that it will execute in serial. Therefore I check if the OnceCell has already been initialized to avoid an unnecessary panic.

This works and from the logs I can see that only one function actually sets up the entity first flow.

However, once it actually reaches a point where an insert happens on the test that actually has performed the entity registration has actually created the database with all entities, which is usually the one that executes first. The other test does not get access to the same database or rather it does not have the same database as all tables seem to be missing.

If I run both tests individually, not within the same cargo test -- --test <name> run, both work as they should with no errors.

So the tokio::OnceCell portion works when running the same function for both tests. The cell gets populated as otherwise the init_db() function would panic / throw an error, but the actually database was only created for one of the tests calling the function.

Is this guide still up to date or rather how could I test this properly, since it seems I'm doing something wrong?

Thanks in advance.

[leuchthelp]

oh and here is the log

running 4 tests
2026-07-24T13:14:19.229130Z  INFO sqlx::query: summary="PRAGMA foreign_keys = ON; …" db.statement="\n\nPRAGMA foreign_keys = ON; \n" rows_affected=0 rows_returned=0 elapsed=30.197µs elapsed_secs=3.0197e-5
2026-07-24T13:14:19.229342Z  INFO sqlx::query: summary="SELECT sqlite_version()" db.statement="" rows_affected=0 rows_returned=1 elapsed=72.906µs elapsed_secs=7.2906e-5
2026-07-24T13:14:19.229691Z  INFO sqlx::query: summary="SELECT \"name\" FROM \"sqlite_master\" …" db.statement="\n\nSELECT \"name\" FROM \"sqlite_master\" WHERE \"type\" = ? AND \"name\" <> ?\n" rows_affected=0 rows_returned=0 elapsed=61.314µs elapsed_secs=6.1314e-5
2026-07-24T13:14:19.229806Z  INFO sqlx::query: summary="SELECT \"name\" FROM \"sqlite_master\" …" db.statement="\n\nSELECT \"name\" FROM \"sqlite_master\" WHERE \"type\" = ? AND \"name\" <> ?\n" rows_affected=0 rows_returned=0 elapsed=5.15µs elapsed_secs=5.15e-6
2026-07-24T13:14:19.230044Z  INFO sqlx::query: summary="CREATE TABLE \"providers\" ( …" db.statement="\n\nCREATE TABLE \"providers\" ( \"server_id\" uuid_text NOT NULL PRIMARY KEY, \"user_id\" uuid_text NOT NULL UNIQUE, \"kind\" varchar NOT NULL, \"url\" varchar NOT NULL )\n" rows_affected=0 rows_returned=0 elapsed=98.894µs elapsed_secs=9.8894e-5
2026-07-24T13:14:19.230231Z  INFO sqlx::query: summary="CREATE TABLE \"media_items\" ( …" db.statement="\n\nCREATE TABLE \"media_items\" ( \"uuid\" uuid_text NOT NULL PRIMARY KEY UNIQUE, \"kind\" varchar NOT NULL, \"outline_gradient\" varchar NOT NULL, \"loaded\" boolean NOT NULL, \"local\" varchar NOT NULL )\n" rows_affected=0 rows_returned=0 elapsed=79.338µs elapsed_secs=7.9338e-5
2026-07-24T13:14:19.230419Z  INFO sqlx::query: summary="CREATE TABLE \"content\" ( …" db.statement="\n\nCREATE TABLE \"content\" ( \"id\" integer NOT NULL PRIMARY KEY AUTOINCREMENT, \"parent_id\" uuid_text, \"kind\" varchar NOT NULL UNIQUE, \"description\" varchar NOT NULL, FOREIGN KEY (\"parent_id\") REFERENCES \"media_items\" (\"uuid\") )\n" rows_affected=0 rows_returned=0 elapsed=99.616µs elapsed_secs=9.9616e-5
2026-07-24T13:14:19.230610Z  INFO sqlx::query: summary="CREATE TABLE \"jt_media_item_to_provider\" ( …" db.statement="\n\nCREATE TABLE \"jt_media_item_to_provider\" ( \"media_item_id\" uuid_text NOT NULL, \"provider_id\" uuid_text NOT NULL, CONSTRAINT \"pk-jt_media_item_to_provider\" PRIMARY KEY (\"media_item_id\", \"provider_id\"), FOREIGN KEY (\"media_item_id\") REFERENCES \"media_items\" (\"uuid\"), FOREIGN KEY (\"provider_id\") REFERENCES \"providers\" (\"user_id\") )\n" rows_affected=0 rows_returned=0 elapsed=88.505µs elapsed_secs=8.8505e-5
2026-07-24T13:14:19.230805Z  INFO sqlx::query: summary="CREATE TABLE \"images\" ( …" db.statement="\n\nCREATE TABLE \"images\" ( \"url\" varchar NOT NULL PRIMARY KEY UNIQUE, \"server_id\" uuid_text, \"kind\" varchar NOT NULL, FOREIGN KEY (\"server_id\") REFERENCES \"providers\" (\"server_id\") )\n" rows_affected=0 rows_returned=0 elapsed=86.041µs elapsed_secs=8.6041e-5
2026-07-24T13:14:19.231025Z  INFO sqlx::query: summary="CREATE TABLE \"jt_media_item_to_image\" ( …" db.statement="\n\nCREATE TABLE \"jt_media_item_to_image\" ( \"media_item_id\" uuid_text NOT NULL, \"image_url\" varchar NOT NULL, CONSTRAINT \"pk-jt_media_item_to_image\" PRIMARY KEY (\"media_item_id\", \"image_url\"), FOREIGN KEY (\"media_item_id\") REFERENCES \"media_items\" (\"uuid\"), FOREIGN KEY (\"image_url\") REFERENCES \"images\" (\"url\") )\n" rows_affected=0 rows_returned=0 elapsed=84.217µs elapsed_secs=8.4217e-5
2026-07-24T13:14:19.231189Z  INFO sqlx::query: summary="CREATE TABLE \"original\" ( …" db.statement="\n\nCREATE TABLE \"original\" ( \"id\" integer NOT NULL PRIMARY KEY AUTOINCREMENT, \"parent_id\" uuid_text, \"server_id\" uuid_text NOT NULL, \"uuid\" uuid_text NOT NULL, \"url\" varchar NOT NULL UNIQUE, FOREIGN KEY (\"parent_id\") REFERENCES \"media_items\" (\"uuid\") )\n" rows_affected=0 rows_returned=0 elapsed=70.973µs elapsed_secs=7.0973e-5
2026-07-24T13:14:19.231355Z  INFO sqlx::query: summary="CREATE TABLE \"jt_parent_to_child\" ( …" db.statement="\n\nCREATE TABLE \"jt_parent_to_child\" ( \"parent_id\" uuid_text NOT NULL, \"child_id\" uuid_text NOT NULL, CONSTRAINT \"pk-jt_parent_to_child\" PRIMARY KEY (\"parent_id\", \"child_id\"), FOREIGN KEY (\"parent_id\") REFERENCES \"media_items\" (\"uuid\"), FOREIGN KEY (\"child_id\") REFERENCES \"media_items\" (\"uuid\") )\n" rows_affected=0 rows_returned=0 elapsed=71.083µs elapsed_secs=7.1083e-5
test provider_manager::provider_manager_test::hash_no_login_failure ... ok
test jellyfin::jellyfin_provider::variant_jellyfin::matching_name ... ok
2026-07-24T13:14:19.390605Z  INFO sqlx::query: summary="INSERT INTO \"providers\" (\"server_id\", …" db.statement="\n\nINSERT INTO \"providers\" (\"server_id\", \"user_id\", \"kind\", \"url\") VALUES (?, ?, ?, ?) RETURNING \"server_id\", \"user_id\", \"kind\", \"url\"\n" rows_affected=0 rows_returned=1 elapsed=100.247µs elapsed_secs=0.000100247
2026-07-24T13:14:19.391889Z  INFO sqlx::query: summary="DELETE FROM \"providers\" WHERE …" db.statement="\n\nDELETE FROM \"providers\" WHERE \"providers\".\"user_id\" = ?\n" rows_affected=1 rows_returned=0 elapsed=39.354µs elapsed_secs=3.9354e-5
test provider_manager::provider_manager_test::try_provider_manager_flow ... ok
2026-07-24T13:14:19.554617Z  INFO sqlx::query: summary="PRAGMA foreign_keys = ON; …" db.statement="\n\nPRAGMA foreign_keys = ON; \n" rows_affected=0 rows_returned=0 elapsed=24.296µs elapsed_secs=2.4296e-5
2026-07-24T13:14:19.554769Z  INFO sqlx::query: summary="INSERT INTO \"providers\" (\"server_id\", …" db.statement="\n\nINSERT INTO \"providers\" (\"server_id\", \"user_id\", \"kind\", \"url\") VALUES (?, ?, ?, ?) RETURNING \"server_id\", \"user_id\", \"kind\", \"url\"\n" rows_affected=0 rows_returned=0 elapsed=66.134µs elapsed_secs=6.6134e-5

thread 'jellyfin::jellyfin_provider::variant_jellyfin::try_auth_flow' (149675) panicked at journey-provider/src/jellyfin/jellyfin_provider.rs:232:14:
called `Result::unwrap()` on an `Err` value: DbError(Query(SqlxError(Database(SqliteError { code: 1, message: "no such table: providers" }))))
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
test jellyfin::jellyfin_provider::variant_jellyfin::try_auth_flow ... FAILED

failures:

failures:
    jellyfin::jellyfin_provider::variant_jellyfin::try_auth_flow

test result: FAILED. 3 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.33s

error: test failed, to rerun pass `-p journey-provider --lib`

[Huliiiiii]

This is because the connection is dropped after the test ends. Therefore, the sqlite in memory is also dropped (because there is no connection). Subsequent tests will recreate a one.

[leuchthelp]

Assumed as much, so this kind on approach just simply doesn’t work for tests I guess.

Interesting thought that the OnceCell isn’t also dropped. I would have thought it would drop too. But only the connection inside gets dropped while the cell stays intact thinking that its contents are also intact.