tree 627227726b93c4c1c5f86b4f8b44fc8ad5fbee99
parent 14deb7d32c91e05ae48e468c07882596e750ed52
author Stephen J Day <stephen.day@docker.com> 1486173920 -0800
committer Victor Vieux <victorvieux@gmail.com> 1486422143 -0800

cluster/executor: check mounts at start

While it is important to not create controllers for an invalid task,
certain properties should only be checked immediately before use. Early
host validation of mounts prevents resolution of the task Executor when
the mounts are not relevant to execution flow. In this case, we have a
check for the existence of a bind mount path in a creation function that
prevents a task controller from being resolved. Such early validation
prevents one from interacting directly with a controller and result in
unnecessary error reporting.

In accordance with the above, we move the validation of the existence of
host bind mount paths to the `Controller.Start` phase. We also call
these "checks", as they are valid mounts but reference non-existent
paths.

Signed-off-by: Stephen J Day <stephen.day@docker.com>
(cherry picked from commit 92899ffac8ca1136e807dd234e8fa1dd49db7801)
Signed-off-by: Victor Vieux <victorvieux@gmail.com>