Typescript scheduled tables fail to generate correctly

[dusk125]

I'm having some trouble getting a scheduled table (and its reducer) to build.

If they're defined in the same file (as it shows in the documentation):

// schema.ts
export const user_reservation_cleaner = table(
  {
    name: 'user_reservation_cleaner',
    public: false,
    scheduled: (): any => release_user_reservation,
  },
  {
    name: t.string().primaryKey(),
    scheduled_at: t.scheduleAt(),
  },
)

export const db = schema({user_reservation_cleaner})

export const release_user_reservation = db.reducer(
  { arg: user_reservation_cleaner.rowType },
  (ctx, { arg }) => {
    ctx.db.user_reservation.name.delete(arg.name)
  },
)

Then I receive the following error when running spacetime generate:

Extracting schema from <project>/spacetimedb/dist/bundle.js...                                                                                                                                                       
Error: Uncaught TypeError: Table user_reservation_cleaner defines a schedule, but it seems like the associated function was not exported.
        at resolveSchedules (node_modules/spacetimedb/dist/server/index.mjs:7263:15)
        at [SpacetimeDB.moduleHooks.v2] (node_modules/spacetimedb/dist/server/index.mjs:7291:22)
Error: could not extract schema

Instead, if I separate the reducer into its own file:

// schema.ts
import { release_user_reservation } from './schedule'

export const user_reservation_cleaner = table(
  {
    name: 'user_reservation_cleaner',
    public: false,
    scheduled: (): any => release_user_reservation,
  },
  {
    name: t.string().primaryKey(),
    scheduled_at: t.scheduleAt(),
  },
)

export const db = schema({user_reservation_cleaner})

// schedule.ts
import { db, user_reservation_cleaner } from './schema'

export const release_user_reservation = db.reducer(
  { arg: user_reservation_cleaner.rowType },
  (ctx, { arg }) => {
    ctx.db.user_reservation.name.delete(arg.name)
  },
)

I receive the following error:

[CIRCULAR_DEPENDENCY] Warning: Circular dependency: src/schema.ts -> src/schedule.ts -> src/schema.ts.

Build finished successfully.
Extracting schema from <project>/spacetimedb/dist/bundle.js...                                                                                                                                                                    
Error: Uncaught ReferenceError: Cannot access 'db' before initialization
        at <anonymous> (src/schedule.ts:3:41)
Error: could not extract schema

Not sure if this is a bug, or if I'm doing something wrong, any recommendations would be much appreciated!

[Xtrazyx]

I also am puzzled by the dependency hierarchy (which is indeed circular). The only out i see for now is to give an empty schema to the scheduled reducer function like in the docs (Core concepts > Tables > schedule-tables).

export const db = schema({})

Doing so prevents you from having any side effect on the other tables, may be is it intended ?

[dusk125]

That seems odd since the docs mention using scheduled tasks for cleanup tasks...which (at least IMO) imply that there would be side effects in other tables.

[NullP0inter]

I am seeing this same issue. In 1.0 the scheduled reducers were referenced by just a string value so they could be resolved later and not have the circular issue. Not sure how this is supposed to work in 2.0 yet separated out in different files.

[NullP0inter]

I retested this again with the table and reducer in the same file similar to your first example with a schema.ts and was able to get it to compile at least. The reducer just needs to be exported in the index.ts something like this.

https://spacetimedb.com/docs/tables/schedule-tables/#defining-a-schedule-table

// index.ts
import { spacetimedb, send_reminder } from "./schema";
export default spacetimedb;
export { send_reminder };

[JasonAtClockwork]

@dusk125 thanks for reporting this. I dug in at the two separate issues:

For the original single-file example I wasn’t able to reproduce the exact error you saw (including after testing back on 2.0.3). With the issue snippet as written, I instead get:

A scheduled table must have columns `scheduled_id: u64` and `scheduled_at: ScheduledAt`, but table
`user_reservation_cleaner` has columns ProductType {"name": String, "scheduled_at": Sum(SumType
{"Interval": Product(ProductType {"__time_duration_micros__": I64}), "Time": Product(ProductType
{"__timestamp_micros_since_unix_epoch__": I64})})}```

This makes sense as the table was missing the required `scheduled_id` column. It's possible the error wasn't showing properly with the version you were on at the time which is why I tried going back to `2.0.3`.

The split-file version is a real problem with the current TypeScript API. The scheduled table references a reducer export, while the reducer is created from db.reducer(...). When those are split across modules, that creates a circular runtime dependency: the table module needs the reducer export, and the reducer module needs db from the schema module. In ESM that fails during module initialization with ReferenceError: Cannot access 'db' before initialization.

I’m looking into whether there is a clean way around that second issue, but at the moment it looks like a real limitation of the current TS scheduled-table API rather than just a problem in your example.