Not all clients and systems can support SPDY protocols. This commit adds
support for two new websocket protocols, one to handle streaming of pod
logs from a pod, and the other to allow exec to be tunneled over
websocket.
Browser support for chunked encoding is still poor, and web consoles
that wish to show pod logs may need to make compromises to display the
output. The /pods/<name>/log endpoint now supports websocket upgrade to
the 'binary.k8s.io' subprotocol, which sends chunks of logs as binary to
the client. Messages are written as logs are streamed from the container
daemon, so flushing should be unaffected.
Browser support for raw communication over SDPY is not possible, and
some languages lack libraries for it and HTTP/2. The Kubelet supports
upgrade to WebSocket instead of SPDY, and will multiplex STDOUT/IN/ERR
over websockets by prepending each binary message with a single byte
representing the channel (0 for IN, 1 for OUT, and 2 for ERR). Because
framing on WebSockets suffers from head-of-line blocking, clients and
other server code should ensure that no particular stream blocks. An
alternative subprotocol 'base64.channel.k8s.io' base64 encodes the body
and uses '0'-'9' to represent the channel for ease of use in browsers.
Increase the supported controls on pod logging. Add validaiton to pod
log options. Ensure the Kubelet is using a consistent, structured way to
process pod log arguments.
Add ?sinceSeconds=<durationInSeconds>, &sinceTime=<RFC3339>, ?timestamps=<bool>,
?tailLines=<number>, and ?limitBytes=<number>
Avoid TTL by deleting pods immediately when they aren't
scheduled, and letting the Kubelet delete them otherwise.
Ensure the Kubelet uses pod.Spec.TerminationGracePeriodSeconds
when no pod.DeletionGracePeriodSeconds is available.
This commit wires together the graceful delete option for pods
on the Kubelet. When a pod is deleted on the API server, a
grace period is calculated that is based on the
Pod.Spec.TerminationGracePeriodInSeconds, the user's provided grace
period, or a default. The grace period can only shrink once set.
The value provided by the user (or the default) is set onto metadata
as DeletionGracePeriod.
When the Kubelet sees a pod with DeletionTimestamp set, it uses the
value of ObjectMeta.GracePeriodSeconds as the grace period
sent to Docker. When updating status, if the pod has DeletionTimestamp
set and all containers are terminated, the Kubelet will update the
status one last time and then invoke Delete(pod, grace: 0) to
clean up the pod immediately.
Change the signature of GuaranteedUpdate so that TTL can
be more easily preserved. Allow a simpler (no ttl) and
more complex (response and node directly available, set ttl)
path for GuaranteedUpdate. Add some tests to ensure this
doesn't blow up again.
The Spec.Host is set when binding a pod to a node and will contain the
canonical host name of the node. The Status.HostIP may not be included
in the node's server TLS certificate.
Makes it possible to access the following subresources:
/namespaces/<ns>/pods/<pod-name>[:port]/proxy
/namespaces/<ns>/pods/<pod-name>/exec?container=<container>&command=<cmd>
/namespaces/<ns>/pods/<pod-name>/portforward
PodExecOptions represents the URL parameters used to invoke an
exec request on a pod. PodProxyOptions contains the path parameter
passed to a proxy request.
Allows REST consumers to build paths like:
/api/v1beta3/namespaces/foo/webhookresource/<name>/<encodedsecretinurl>
Also fixes parameter exposure for subresources (was only fixed for
v1beta3).
Adds a Log subresource to Pod storage. The Log subresource implements
rest.GetterWithOptions and produces a ResourceStreamer resource that
will stream the log output from the pod's host node.
Convert the return value of pods rest.NewStorage to a struct.
This will allow returning more storage objects for a pod (sub resources)
without awkwardly adding more return values.
As per discussion with @snmarterclayton. I implemented this for most
types in the "obvious" way. I am not sure how to implement
this for a couple types, though.
Dependency chain is now api -> api/rest -> apiserver. Makes the
interfaces much cleaner to read, and cleans up some inconsistenties
that crept in along the way.
This commit adds support to core resources to enable deferred deletion
of resources. Clients may optionally specify a time period after which
resources must be deleted via an object sent with their DELETE. That
object may define an optional grace period in seconds, or allow the
default "preferred" value for a resource to be used. Once the object
is marked as pending deletion, the deletionTimestamp field will be set
and an etcd TTL will be in place.
Clients should assume resources that have deletionTimestamp set will
be deleted at some point in the future. Other changes will come later
to enable graceful deletion on a per resource basis.
In order to support graceful deletion, the resource object will
need access to the TTL value in etcd. Also, in the future we
may want to get the creation index (distinct from modifiedindex)
and expose it to clients. Change EtcdResourceVersioner to be
more type specific (objects vs lists) and provide a default
implementation that relies on the internal API convention.
Also, rename etcd_tools.go to etcd_helper.go and split a few
things up.
