payloadcms/payload · error · APIError

Assertion for DB name of ${name} ${slug} was failed.

Error message

Assertion for DB name of ${name} ${slug} was failed.

What it means

Thrown by `getDBName` after resolving the name from `custom` (function result or string), then `name`, then `slug`, and applying the `_versions` suffix. If `result` is still falsy, the adapter cannot name the underlying MongoDB collection, so it aborts. The message interpolates `name` and `slug` to help identify the offending entity.

Source

Thrown at packages/db-mongodb/src/utilities/getDBName.ts:43

  let result: null | string = null
  let custom = config[target]

  if (!custom && target === 'enumName') {
    custom = config['dbName']
  }

  if (custom) {
    result = typeof custom === 'function' ? custom({}) : custom
  } else {
    result = name ?? slug ?? null
  }

  if (versions) {
    result = `_${result}_versions`
  }

  if (!result) {
    throw new APIError(`Assertion for DB name of ${name} ${slug} was failed.`)
  }

  return result
}

View on GitHub (pinned to 00c58b35c0)

Solutions

1. Ensure every collection and global has a non-empty `slug`.
2. If using `dbName` as a function, always return a non-empty string.
3. Set `dbName` explicitly on the entity flagged by the `${name} ${slug}` interpolation.
4. Audit programmatic config builders to guarantee `slug` is assigned.

Example fix

// before
{ slug: '', fields: [...] }
// after
{ slug: 'posts', fields: [...] }

function assertDbName({ name, slug, dbName }) {
  const resolved = typeof dbName === 'function' ? dbName({}) : (dbName ?? name ?? slug)
  if (!resolved) throw new Error(`Cannot resolve DB name for slug=${slug}`)
}

const hasResolvableDbName = (c) =>
  Boolean((typeof c.dbName === 'function' ? c.dbName({}) : c.dbName) ?? c.name ?? c.slug)

try { await payload.init() }
catch (e) { if (/Assertion for DB name/.test(e.message)) auditConfigSlugs() else throw e }

When it happens

Trigger: `getDBName` invoked on a config where `dbName` is unset (or its function returns null/empty) AND both `name` and `slug` are null/empty strings.

Common situations: A collection/global config constructed programmatically without setting `slug`; a custom `dbName` function that returns undefined under some condition; a config object spread that dropped the slug field.

Related errors

• Global with the slug ${globalSlug} was not found
• Collection with the slug ${globalSlug} was not found
• ERROR: Failed to retrieve collection with the slug "${collec
• ERROR: Failed to retrieve global with the slug "${globalSlug
• Fields are not initialized.

AI-assisted analysis of payloadcms/payload@00c58b35c0 (2026-08-12). Data as JSON: /api/errors/ae3ad84fb6be9e48. Report an issue: GitHub.