glance_store.capabilities module

Glance Store capability

class glance_store.capabilities.BitMasks(value)

Bases: IntEnum

An enumeration.

ALL = 255

DRIVER_REUSABLE = 64

NONE = 0

READ_ACCESS = 1

READ_CHUNK = 5

READ_OFFSET = 3

READ_RANDOM = 7

RW_ACCESS = 9

RW_CHUNK = 45

RW_OFFSET = 27

RW_RANDOM = 63

WRITE_ACCESS = 8

WRITE_CHUNK = 40

WRITE_OFFSET = 24

WRITE_RANDOM = 56

class glance_store.capabilities.StoreCapability

Bases: object

property capabilities

static contains(x, y)

is_capable(*capabilities)

Check if requested capability(s) are supported by current driver instance.

Parameters:

capabilities – required capability(s).

set_capabilities(*dynamic_capabilites)

Set dynamic storage capabilities based on current driver configuration and backend status.

Parameters:

dynamic_capabilites – dynamic storage capability(s).

unset_capabilities(*dynamic_capabilites)

Unset dynamic storage capabilities.

Parameters:

dynamic_capabilites – dynamic storage capability(s).

update_capabilities()

Update dynamic storage capabilities based on current driver configuration and backend status when needed.

As a hook, the function will be triggered in two cases: calling once after store driver get configured, it was used to update dynamic storage capabilities based on current driver configuration, or calling when the capabilities checking of an operation failed every time, this was used to refresh dynamic storage capabilities based on backend status then.

This function shouldn’t raise any exception out.

glance_store.capabilities.check(store_op_fun)