Touch/Expiry

Detailed Description

Modify or clear a document's expiration time.

Couchbase allows documents to contain expiration times (see lcb_CMDBASE::exptime). Most operations allow the expiry time to be updated, however lcb_touch3() allows the exclusive update of the expiration time without additional network overhead.

Functions
lcb_error_t	lcb_touch3 (lcb_t instance, const void *cookie, const lcb_CMDTOUCH *cmd)
	Spool a touch request. More...

Typedefs
typedef lcb_CMDBASE	lcb_CMDTOUCH
	Command structure for a touch request. More...
typedef lcb_RESPBASE	lcb_RESPTOUCH
	Response structure for a touch request. More...

Function Documentation

lcb_error_t lcb_touch3	(	lcb_t	instance,
		const void *	cookie,
		const lcb_CMDTOUCH *	cmd
	)

Spool a touch request.

Stability

Committed:

Parameters

instance	the handle
cookie	the pointer to associate with the request
cmd	the command

Returns

LCB_SUCCESS on success, other error code on failure

Request

lcb_CMDTOUCH cmd = { 0 };
LCB_CMD_SET_KEY(&cmd, "keep_me", strlen("keep_me"));
cmd.exptime = 0; // Clear the expiration
lcb_touch3(instance, cookie, &cmd);

Response

lcb_install_callback3(instance, LCB_CALLBACK_TOUCH, touch_callback);
void touch_callback(lcb_t instance, int cbtype, const lcb_RESPBASE *rb)
{
    if (rb->rc == LCB_SUCCESS) {
        printf("Touch succeeded\n");
    }
}

Typedef Documentation

typedef lcb_CMDBASE lcb_CMDTOUCH

Command structure for a touch request.

Note

The lcb_CMDTOUCH::cas field is ignored. The item's modification time is always updated regardless if the CAS on the server differs. The #exptime field is always used. If 0 then the expiry on the server is cleared.

typedef lcb_RESPBASE lcb_RESPTOUCH

Response structure for a touch request.

Note

the lcb_RESPTOUCH::cas field contains the current CAS of the item