In the course of setting out to add filters and address some cleanup, it
was found that we had a few problems in the events subsystem that needed
addressing before moving forward.
The biggest change was to move to the more standard terminology of
publish and subscribe. We make this terminology change across the Go
interface and the GRPC API, making the behavior more familier. The
previous system was very context-oriented, which is no longer required.
With this, we've removed a large amount of dead and unneeded code. Event
transactions, context storage and the concept of `Poster` is gone. This
has been replaced in most places with a `Publisher`, which matches the
actual usage throughout the codebase, removing the need for helpers.
There are still some questions around the way events are handled in the
shim. Right now, we've preserved some of the existing bugs which may
require more extensive changes to resolve correctly.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
This avoids someone adding a new error path and forgetting to call the cleanup
function.
We prefer to use an explicit flag to gate the clean rather than relying on `err
!= nil` so we don't have to rely on people never accidentally shadowing the
`err` as seen by the closure.
Signed-off-by: Ian Campbell <ian.campbell@docker.com>
Mounting as MS_SLAVE here breaks use cases which want to use
rootPropagation=shared in order to expose mounts to the host (and other
containers binding the same subtree), mounting as e.g. MS_SHARED is pointless
in this context so just remove.
Having done this we also need to arrange to manually clean up the mounts on
delete, so do so.
Note that runc will also setup root as required by rootPropagation, defaulting
to MS_PRIVATE.
Fixes#1132.
Signed-off-by: Ian Campbell <ian.campbell@docker.com>
Since we now have a common set of error definitions, mapped to existing
error codes, we no longer need the specialized error codes used for
interaction with linux processes. The main issue was that string
matching was being used to map these to useful error codes. With this
change, we use errors defined in the `errdefs` package, which map
cleanly to GRPC error codes and are recoverable on either side of the
request.
The main focus of this PR was in removin these from the shim. We may
need follow ups to ensure error codes are preserved by the `Tasks`
service.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
After review, there are cases where having common requirements for
namespaces and identifiers creates contention between applications. One
example is that it is nice to have namespaces comply with domain name
requirement, but that does not allow underscores, which are required for
certain identifiers.
The namespaces validation has been reverted to be in line with RFC 1035.
Existing identifiers has been modified to allow simply alpha-numeric
identifiers, while limiting adjacent separators.
We may follow up tweaks for the identifier charset but this split should
remove the hard decisions.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
This removes the RuntimeEvent super proto with enums into separate
runtime event protos to be inline with the other events that are output
by containerd.
This also renames the runtime events into Task* events.
Fixes#1071
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This makes it possible to enable shim debug by adding the following to
`config.toml`:
[plugins.linux]
shim_debug = true
I moved the debug setting from the `client.Config struct` to an argument to
`client.WithStart` since this is the only place it would be used.
Signed-off-by: Ian Campbell <ian.campbell@docker.com>
We hope that containerd supports any OCI compliant runtime, and not only
runc.
This patch fixes all the error messages to not be completely runc
specific and change the initProcess structure to have its runtime
pointer be called 'runtime' and not 'runc'
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
These rpcs only return pids []uint32 so should be named that way in
order to have other rpcs that list Processes such as Exec'd processes.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This moves the shim's API and protos out of the containerd services
package and into the linux runtime package. This is because the shim is
an implementation detail of the linux runtime that we have and it is not
a containerd user facing api.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
We need a separate API for handing the exit status and deletion of
Exec'd processes to make sure they are properly cleaned up within the
shim and daemon.
Fixes#973
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This allows attach of existing fifos to be done without any information
stored on the client side.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This also fixes a deadlock in the shim's reaper where execs would lockup
and/or miss a quick exiting exec process's exit status.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
There are three aspects which need to be covered:
- the runtime needs to restart its event pump when it reconnects (in
loadContainer).
- on the server side shim needs to monitor the stream context so it knows when
the connection goes away.
- if the shim's stream.Send() fails (because the stream died between taking
the event off the channel and calling stream.Send()) then to avoid losing
that event the shim should remember it and send it out first on the next
stream.
The shim's event production machinery only handles producing a single event
stream, so add an interlock to ensure there is only one reader of the
`s.events` channel at a time. Subsequent attempts to use Events will block
until the existing owner is done.
Fixes#921.
Signed-off-by: Ian Campbell <ian.campbell@docker.com>
Working from feedback on the existing implementation, we have now
introduced a central metadata object to represent the lifecycle and pin
the resources required to implement what people today know as
containers. This includes the runtime specification and the root
filesystem snapshots. We also allow arbitrary labeling of the container.
Such provisions will bring the containerd definition of container closer
to what is expected by users.
The objects that encompass today's ContainerService, centered around the
runtime, will be known as tasks. These tasks take on the existing
lifecycle behavior of containerd's containers, which means that they are
deleted when they exit. Largely, there are no other changes except for
naming.
The `Container` object will operate purely as a metadata object. No
runtime state will be held on `Container`. It only informs the execution
service on what is required for creating tasks and the resources in use
by that container. The resources referenced by that container will be
deleted when the container is deleted, if not in use. In this sense,
users can create, list, label and delete containers in a similar way as
they do with docker today, without the complexity of runtime locks that
plagues current implementations.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
