This commit adds a Binding object. The idea is that schedulers can write
these to cause pods to be asssigned to hosts. I'll provide an implementation
along with a rudimentary scheduler plugin.
This continues k8s' tradition of phrasing all APIs as RESTful handlers.
1. Change names of Pod statuses (Waiting, Running, Terminated).
2. Store assigned host in etcd.
3. Change pod key to /registry/pods/<podid>. Container location remains
the same (/registry/hosts/<machine>/kublet).
* Add labels selector (same as List)
* Add fields selector
* Plan to let you select pods by Host and/or Status
* Add resourceVersion to let you resume a watch where you left off.
The apiserver on initialization must be provided with a codec
for encoding and decoding all handled objects including api.Status
and api.ServerOp. In addition, the RESTStorage Extract() method
has been changed to New(), which returns a pointer object that the
codec must decode into (the internal object). Switched registry
methods to use pointers for Create/Update instead of values.
Contains breaking API change on api.Status#Details (type change)
Turn Details from string -> StatusDetails - a general
bucket for keyed error behavior. Define an open enumeration
ReasonType exposed as Reason on the status object to provide
machine readable subcategorization beyond HTTP Status Code. Define
a human readable field Message which is common convention (previously
this was joined into Details).
Precedence order: HTTP Status Code, Reason, Details. apiserver would
impose restraints on the ReasonTypes defined by the main apiobject,
and ensure their use is consistent.
There are four long term scenarios this change supports:
1. Allow a client access to a machine readable field that can be
easily switched on for improving or translating the generic
server Message.
2. Return a 404 when a composite operation on multiple resources
fails with enough data so that a client can distinguish which
item does not exist. E.g. resource Parent and resource Child,
POST /parents/1/children to create a new Child, but /parents/1
is deleted. POST returns 404, ReasonTypeNotFound, and
Details.ID = "1", Details.Kind = "parent"
3. Allow a client to receive validation data that is keyed by
attribute for building user facing UIs around field submission.
Validation is usually expressed as map[string][]string, but
that type is less appropriate for many other uses.
4. Allow specific API errors to return more granular failure status
for specific operations. An example might be a minion proxy,
where the operation that failed may be both proxying OR the
minion itself. In this case a reason may be defined "proxy_failed"
corresponding to 502, where the Details field may be extended
to contain a nested error object.
At this time only ID and Kind are exposed
etcd_tools.go is not dependent on the specific implementation
(which is provided by pkg/api). All EtcdHelpers are created
with an encoding object which handles Encode/Decode/DecodeInto.
Additional tests added to verify simple atomic flows.
Begins to break up api singleton pattern.
Files that have RESTStorage implementations now end in "storage", and
files that have registries now end in "registry". I removed some
underscores in file names, since it seems to be go style not to have
them. I split minion_registry.go into two files.
We should consider splitting this package into two, to make more clear
the separation between the layers.
To make sure the etcd watcher works, I changed the replication
controller to use watch.Interface. I made apiserver support watches on
controllers, so replicationController can be run only off of the
apiserver. I made sure all the etcd watch testing that used to be in
replicationController is now tested on the new etcd watcher in
pkg/tools/.
If a service is deleted before the etcd key corresponding to its
endpoints has been created, a 500 error is returned (etcd key
not found). Instead, key not found should be ignored silently.
There is a potential race condition with the controller creating
endpoints after the service has been deleted which a cleanup task
should handle in the future.
Closes#684
Return all healthy minions instead of only returning the first several
healthy minions. Without the PR, if the first minion failed with health
check, the machine list is empty, thus GET /api/v1beta1/pods failed
with code 500
The current tests for the health package utilize a fake HTTP client
for testing health checks and only cover a limited set of test cases.
This patch removes the need for mocks by using the httptest package
from the standard library. After removing the fake HTTP client a bug
was found in the health.Check function; it incorrectly assumes that
a http.Response is always non-nil. Fix the issue by moving the defer
that closes the http.Response.Body after error handling.
Related tests in the registry package have be refactored to work with
the changes made to the health.Check function. All methods that implement
the health.HTTPGetInterface interface now return a http.Response with
with a noop http.Response.Body.
This patch does not introduce any changes in behavior.
