option in routes is used to override default resource identifier i.e. :id.
Let’s take for an example that we want product :name to be as the default
resource identifier instead of :id while defining routes for products. In this
option comes handy. We will see below how we can use this option.
Before Rails 6, if
resource custom param
contains a colon, Rails used to consider that as an extra param which should not be the case because
it sneaks in an extra param.
was raised in Aug, 2017 which was later fixed in February this year.