Inspect item's Replication and Persistence

Detailed Description

Determine if an item exists and if it has been replicated and persisted to various nodes.

Functions
lcb_observe_callback	lcb_set_observe_callback (lcb_t, lcb_observe_callback)
lcb_error_t	lcb_observe (lcb_t instance, const void *command_cookie, lcb_SIZE num, const lcb_observe_cmd_t *const *commands)
	Observe key. More...

Macros
#define	LCB_OBSERVE_FIELDS_COMMON

Typedefs
typedef void(*	lcb_observe_callback )(lcb_t instance, const void *cookie, lcb_error_t error, const lcb_observe_resp_t *resp)
	The callback function for an observe request. More...

Enumerations
enum	lcb_observe_options_t
enum	lcb_observe_t
	Possible statuses for keys in OBSERVE response. More...

Function Documentation

lcb_error_t lcb_observe	(	lcb_t	instance,
		const void *	command_cookie,
		lcb_SIZE	num,
		const lcb_observe_cmd_t *const *	commands
	)

Observe key.

lcb_observe_cmd_t *observe = calloc(1, sizeof(*observe));
observe->version = 0;
observe->v.v0.key = "my-key";
observe->v.v0.nkey = strlen(observe->v.v0.key);
lcb_observe_cmd_t* commands[] = { observe };
lcb_observe(instance, NULL, 1, commands);

Parameters

instance	the instance used to batch the requests from
command_cookie	A cookie passed to all of the notifications from this command
num	the total number of elements in the commands array
commands	the array containing the items to observe

Returns

The status of the operation

Stability

Committed:

---

Data Structure Documentation

struct lcb_OBSERVECMDv1

lcb_observe() Command structure

Data Fields
const void *	key
lcb_SIZE	nkey
LCB__HKFIELDS lcb_observe_options_t	options	<@private

struct lcb_observe_cmd_t

lcb_observe() Command wrapper structure

See also

lcb_OBSERVECMDv1

Data Fields
int	version
union lcb_observe_cmd_t	v

struct lcb_OBSERVERESPv0

Response Structure for lcb_observe()

Data Fields
const void *	key
lcb_SIZE	nkey
lcb_cas_t	cas	CAS of the item on this server.
lcb_observe_t	status	Status flags.
int	from_master	zero if key came from replica
lcb_time_t	ttp	average time to persist on this server
lcb_time_t	ttr	average time to replicate on this server

Typedef Documentation

typedef void(* lcb_observe_callback)(lcb_t instance, const void *cookie, lcb_error_t error, const lcb_observe_resp_t *resp)

The callback function for an observe request.

Parameters

instance	the instance performing the operation
cookie	the cookie associated with with the command
error	The status of the operation
resp	More information about the operation (only key and nkey is valid if error != LCB_SUCCESS)

Enumeration Type Documentation

enum lcb_observe_options_t

Enumerator
LCB_OBSERVE_MASTER_ONLY	Only sends a command to the master. In this case the callback will be invoked only once for the master, and then another time with the NULL callback

enum lcb_observe_t

Possible statuses for keys in OBSERVE response.

Enumerator
LCB_OBSERVE_FOUND	The item found in the memory, but not yet on the disk.
LCB_OBSERVE_PERSISTED	The item hit the disk.
LCB_OBSERVE_NOT_FOUND	The item missing on the disk and the memory.
LCB_OBSERVE_LOGICALLY_DELETED	No knowledge of the key :)