Messages

Functions
NATS_EXTERN natsStatus	natsMsg_GetMetaData (jsMsgMetaData **new_meta, natsMsg *msg)
	Returns metadata from this JetStream message.
NATS_EXTERN void	jsMsgMetaData_Destroy (jsMsgMetaData *meta)
	Destroys the message metadata object.
NATS_EXTERN natsStatus	natsMsg_Ack (natsMsg *msg, jsOptions *opts)
	Acknowledges a message.
NATS_EXTERN natsStatus	natsMsg_AckSync (natsMsg *msg, jsOptions *opts, jsErrCode *errCode)
	Acknowledges a message and wait for a confirmation.
NATS_EXTERN natsStatus	natsMsg_Nak (natsMsg *msg, jsOptions *opts)
	Negatively acknowledges a message.
NATS_EXTERN natsStatus	natsMsg_NakWithDelay (natsMsg *msg, int64_t delay, jsOptions *opts)
	Negatively acknowledges a message.
NATS_EXTERN natsStatus	natsMsg_InProgress (natsMsg *msg, jsOptions *opts)
	Resets redelivery timer on the server.
NATS_EXTERN natsStatus	natsMsg_Term (natsMsg *msg, jsOptions *opts)
	Abandon this message.
NATS_EXTERN uint64_t	natsMsg_GetSequence (natsMsg *msg)
	Returns the sequence number of this JetStream message.
NATS_EXTERN int64_t	natsMsg_GetTime (natsMsg *msg)
	Returns the timestamp (in UTC) of this JetStream message.

Detailed Description

Function specific to JetStream messages

Function Documentation

natsMsg_GetMetaData()

NATS_EXTERN natsStatus natsMsg_GetMetaData	(	jsMsgMetaData **	new_meta,
		natsMsg *	msg )

This works only for JetStream messages that have been received through a subscription callback or calling natsSubscription_NextMsg.

Note

The user must destroy the returned object with jsMsgMetaData_Destroy.

This function will return an error for non JetStream messages.

Parameters

new_meta	the location where to store the pointer to the newly created jsMsgMetaData object.
msg	the pointer to the natsMsg object, which should be a JetStream message received through a subscription callback or natsSubscription_NextMsg.

jsMsgMetaData_Destroy()

NATS_EXTERN void jsMsgMetaData_Destroy

(

jsMsgMetaData *

meta

)

Releases memory allocated for this jsMsgMetaData object.

Parameters

meta	the pointer to the jsMsgMetaData object.

natsMsg_Ack()

NATS_EXTERN natsStatus natsMsg_Ack	(	natsMsg *	msg,
		jsOptions *	opts )

This tells the server that the message was successfully processed and it can move on to the next message.

Parameters

msg	the pointer to the natsMsg object.
opts	the pointer to the jsOptions object, possibly NULL.

natsMsg_AckSync()

NATS_EXTERN natsStatus natsMsg_AckSync	(	natsMsg *	msg,
		jsOptions *	opts,
		jsErrCode *	errCode )

This is the synchronous version of natsMsg_Ack. This indicates successful message processing, and waits for confirmation from the server that the acknowledgment has been processed.

Parameters

msg	the pointer to the natsMsg object.
opts	the pointer to the jsOptions object, possibly NULL.
errCode	the location where to store the JetStream specific error code, or NULL if not needed.

natsMsg_Nak()

NATS_EXTERN natsStatus natsMsg_Nak	(	natsMsg *	msg,
		jsOptions *	opts )

This tells the server to redeliver the message. You can configure the number of redeliveries by passing MaxDeliver when you subscribe.

The default is infinite redeliveries.

Parameters

msg	the pointer to the natsMsg object.
opts	the pointer to the jsOptions object, possibly NULL.

natsMsg_NakWithDelay()

NATS_EXTERN natsStatus natsMsg_NakWithDelay	(	natsMsg *	msg,
		int64_t	delay,
		jsOptions *	opts )

This tells the server to redeliver the message after the given delay duration expressed in milliseconds. You can configure the number of redeliveries by passing MaxDeliver when you subscribe.

The default is infinite redeliveries.

Parameters

msg	the pointer to the natsMsg object.
delay	the amount of time before the redelivery expressed in milliseconds.
opts	the pointer to the jsOptions object, possibly NULL.

natsMsg_InProgress()

NATS_EXTERN natsStatus natsMsg_InProgress	(	natsMsg *	msg,
		jsOptions *	opts )

This tells the server that this message is being worked on. It resets the redelivery timer on the server.

Parameters

msg	the pointer to the natsMsg object.
opts	the pointer to the jsOptions object, possibly NULL.

natsMsg_Term()

NATS_EXTERN natsStatus natsMsg_Term	(	natsMsg *	msg,
		jsOptions *	opts )

This tells the server to not redeliver this message, regardless of the value MaxDeliver.

Parameters

msg	the pointer to the natsMsg object.
opts	the pointer to the jsOptions object, possibly NULL.

natsMsg_GetSequence()

NATS_EXTERN uint64_t natsMsg_GetSequence

(

natsMsg *

msg

)

Returns the sequence number of this JetStream message, or 0 if msg is NULL or not a JetStream message.

Note

This applies to JetStream messages retrieved with js_GetMsg or js_GetLastMsg.

Parameters

msg	the pointer to the natsMsg object.

natsMsg_GetTime()

NATS_EXTERN int64_t natsMsg_GetTime

(

natsMsg *

msg

)

Returns the timestamp (in UTC) of this JetStream message, or 0 if msg is NULL or not a JetStream message.

Note

This applies to JetStream messages retrieved with js_GetMsg or js_GetLastMsg.

Parameters

msg	the pointer to the natsMsg object.