Hi Tigerwolf!

Lucid cascades the transaction to relationship operations for us! So, when we attach the transaction to the operation that creates the organization, the transaction reference will be kept in the organization instance.

return db.transaction(async (trx) => {
  const organization = await Organization.create(data, { client: trx })
  
  organization.$trx // 👈 holds the transaction

  // ...
})

  

    

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This transaction reference is then automatically used when we perform subsequent operations with this organization, which includes related operations.

return db.transaction(async (trx) => {
  const organization = await Organization.create(data, { client: trx })
  
  // 👇 passes $trx on the organization along with the attach db operation
  return organization.related('users').attach({
    [user.id]: {
      role_id: Roles.ADMIN,
    },
  })

  // ...
})

  

    

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The managed transaction, then, wraps the callback within a try/catch block. The transaction is committed if the callback completes and no errors are thrown. Otherwise, if an error is caught, the transaction is rolled back. Essentially doing the below for us in a nicer syntax.

const trx = await db.transaction()

try {
  const organization = await Organization.create(data, { client: trx })
  
  // 👇 passes $trx on the organization along with the attach db operation
  return organization.related('users').attach({
    [user.id]: {
      role_id: Roles.ADMIN,
    },
  })

  // ...

  await trx.commit()
} catch (error) {
  await trx.rollback()
}

  

    

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So, as long as we don't eat the errors thrown by the operations we're performing, the managed transaction will catch it and roll back our transaction. This is regardless of how we structure our code within the managed transaction, including splitting it into additional methods.

So, to answer your question, If an issue occurs in assignAdmin or createDefaults the managed transaction will catch this and roll back our transaction for us! You can see this for yourself by trying to assign the user a role_id that doesn't exist. Since we're using a foreign key constraint here, attempting to do so will throw an error.

static async #assignAdmin(organization: Organization, user: User) {
  return organization.related('users').attach({
    [user.id]: {
      role_id: 45, //Roles.ADMIN, // 👈 replace admin with some non-existant id
    },
  })
}

  

    

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