Referential: Raise an error if the table lock times out

Paired with Johan on this one. There's an internal timeout on our table
lock. If it's reached, an
`ActiveRecord::StatementInvalid<PG::LockNotAvailable>` error is raised.
Use a custom error instead by "overriding" `#save` with a method that
raises our custom error in that case instead. This will enable us to
provide a custom user-facing error in the event this happens.

Refs #5024

1 files changed, 1 insertions, 0 deletions

diff --git a/app/errors/table_lock_timeout_error.rb b/app/errors/table_lock_timeout_error.rb
new file mode 100644
index 000000000..102f3a4a0
--- /dev/null
+++ b/app/errors/table_lock_timeout_error.rb
@@ -0,0 +1 @@
+class TableLockTimeoutError < ActiveRecord::StatementInvalid; end