The current structure is a remnant of when the in memory storage was one
of the options for backing store. Today, we always have the memory
storage with an optional "backend storage" plugin. This commit makes the
InMemoryStorage use explicit.
This should make us more robust in the face of failure (at the cost of
making the failures less prominent). We allow GetStats() to return an
error and a partial result. We will process the result and report the
error.
Fixes#306.
The stats are only populated when cAdvisor is running outside network namespaces.
We'll add a different backend to retrieve the same data from within namespaces.
This is read once at start of cAdvisor. We can use this to report
machine state as well as return logical name for block devices in UI.
Signed-off-by: Rohit Jnagal <jnagal@google.com> (github: rjnagal)
This adds an Exists() interface to detect when the container is dead.
Before reporting an update error we check is Exists() is true.
Some documentation was added as well.
This canges the output of the Docker endpoint to be a map so that it is
more consistent from single to multiple returns. It also refactors
internally how we handle both types of requests.
Without this PR the /docker API endpoint is broken completely so this
change in format has no effect anyways.
These changes are tested by the upcoming integration tests.
Since Docker containers are known by more than one name we were
returning them once for every name they're known by. This change makes
the returned containers unique.
This is done by introducting the concept of "namespaces" of container
names. The aliases of a container are under this namespace. Namespace
names are of the form:
//<namespace>/<alias>
This allows us to (within cAdvisor) query all docker containers as
//docker regardless of whether this is a systemd or a non-systemd system.
This does break our ability to handle Docker aliases with the /container
endpoint. I think this is acceptable as our support there was not
consistent between system types.
