fix(watch): fix startup crash when a non-superuser tries to watch (gr…

…aphile#371)

* fix(watch): fix startup crash when non-superuser tries to watch

* Update watchPgSchemas.ts

src/postgraphql/watch/__tests__/watchPgSchemas-test.js

@@ -33,7 +33,11 @@ test('will log some stuff and continue if the watch fixtures query fails', async
   await watchPgSchemas({ pgPool })
   console.warn = origWarn
   expect(pgPool.connect.mock.calls).toEqual([[]])
-  expect(pgClient.query.mock.calls).toEqual([[await _watchFixturesQuery], ['listen postgraphql_watch']])
+  expect(pgClient.query.mock.calls).toEqual([
+    [await _watchFixturesQuery],
+    ['rollback'],
+    ['listen postgraphql_watch'],
+  ])
   expect(pgClient.on.mock.calls.length).toBe(1)
   expect(pgClient.on.mock.calls[0].length).toBe(2)
   expect(pgClient.on.mock.calls[0][0]).toBe('notification')

src/postgraphql/watch/watchPgSchemas.ts

@@ -45,6 +45,7 @@ export default async function watchPgSchemas ({ pgPool, pgSchemas, onChange }: {
     console.warn(chalk.yellow('This is likely because your Postgres user is not a superuser. If the'))
     console.warn(chalk.yellow('fixtures already exist, the watch functionality may still work.'))
     // tslint:enable no-console
+    await pgClient.query('rollback')
   }
 
   // Listen to the `postgraphql_watch` channel. Any and all updates will come