Commands and queries implement request–reply over channels. Commands expect a single response; queries return data payloads and support optional response caching.

Commands

SendCommand

func (c *Client) SendCommand(ctx context.Context, command *Command) (*CommandResponse, error)

Sends a command and blocks until a response arrives or timeout elapses.

Parameters:

Name	Type	Required	Description
`ctx`	`context.Context`	Yes	Overall deadline
`command`	`*Command`	Yes	Channel, body/metadata, `SetTimeout`, tags

Returns: *CommandResponse — execution metadata and payload from responder.

SubscribeToCommands

func (c *Client) SubscribeToCommands(ctx context.Context, channel, group string, opts ...SubscribeOption) (*Subscription, error)

Receives incoming commands for a service. Use handlers configured via SubscribeOption.

SendCommandResponse

func (c *Client) SendCommandResponse(ctx context.Context, response *CommandReply) error

Replies to a command received in the subscription callback.

Queries

SendQuery

func (c *Client) SendQuery(ctx context.Context, query *Query) (*QueryResponse, error)

Sends a query and waits for a typed response. Use SetCacheKey / SetCacheTTL on the Query for server-side cache hints.

SubscribeToQueries

func (c *Client) SubscribeToQueries(ctx context.Context, channel, group string, opts ...SubscribeOption) (*Subscription, error)

Subscribes as a query worker; analogous to commands with different protobuf routing.

SendQueryResponse

func (c *Client) SendQueryResponse(ctx context.Context, response *QueryReply) error

Returns data and metadata to the caller of SendQuery.

Message helpers

Type	Factory	Notes
`Command`	`NewCommand()`	Timeout required for server routing
`Query`	`NewQuery()`	Adds cache key/TTL fields

Quick Usage

rpc.go

cmd := kubemq.NewCommand()
cmd.SetChannel("svc.commands")
cmd.SetBody([]byte("ping"))
cmd.SetTimeout(5 * time.Second)

resp, err := client.SendCommand(ctx, cmd)
if err != nil {
    return err
}
_ = resp.Executed

RPC