"strings"
"time"
- "git.fd.io/govpp.git/api"
"github.com/sirupsen/logrus"
+
+ "git.fd.io/govpp.git/adapter"
+ "git.fd.io/govpp.git/api"
)
var (
ErrInvalidRequestCtx = errors.New("invalid request context")
)
-// requestCtx is a context for request with single reply
-type requestCtx struct {
- ch *channel
- seqNum uint16
+// MessageCodec provides functionality for decoding binary data to generated API messages.
+type MessageCodec interface {
+ // EncodeMsg encodes message into binary data.
+ EncodeMsg(msg api.Message, msgID uint16) ([]byte, error)
+ // DecodeMsg decodes binary-encoded data of a message into provided Message structure.
+ DecodeMsg(data []byte, msg api.Message) error
}
-// multiRequestCtx is a context for request with multiple responses
-type multiRequestCtx struct {
- ch *channel
- seqNum uint16
-}
-
-func (req *requestCtx) ReceiveReply(msg api.Message) error {
- if req == nil || req.ch == nil {
- return ErrInvalidRequestCtx
- }
-
- lastReplyReceived, err := req.ch.receiveReplyInternal(msg, req.seqNum)
- if err != nil {
- return err
- }
- if lastReplyReceived {
- return errors.New("multipart reply recieved while a single reply expected")
- }
-
- return nil
-}
-
-func (req *multiRequestCtx) ReceiveReply(msg api.Message) (lastReplyReceived bool, err error) {
- if req == nil || req.ch == nil {
- return false, ErrInvalidRequestCtx
- }
-
- return req.ch.receiveReplyInternal(msg, req.seqNum)
+// MessageIdentifier provides identification of generated API messages.
+type MessageIdentifier interface {
+ // GetMessageID returns message identifier of given API message.
+ GetMessageID(msg api.Message) (uint16, error)
+ // LookupByID looks up message name and crc by ID
+ LookupByID(msgID uint16) (api.Message, error)
}
// vppRequest is a request that will be sent to VPP.
err error // in case of error, data is nil and this member contains error
}
-// NotifSubscribeRequest is a request to subscribe for delivery of specific notification messages.
-type subscriptionRequest struct {
- sub *api.NotifSubscription // subscription details
- subscribe bool // true if this is a request to subscribe
+// requestCtx is a context for request with single reply
+type requestCtx struct {
+ ch *Channel
+ seqNum uint16
+}
+
+// multiRequestCtx is a context for request with multiple responses
+type multiRequestCtx struct {
+ ch *Channel
+ seqNum uint16
+}
+
+// subscriptionCtx is a context of subscription for delivery of specific notification messages.
+type subscriptionCtx struct {
+ ch *Channel
+ notifChan chan api.Message // channel where notification messages will be delivered to
+ msgID uint16 // message ID for the subscribed event message
+ event api.Message // event message that this subscription is for
+ msgFactory func() api.Message // function that returns a new instance of the specific message that is expected as a notification
}
// channel is the main communication interface with govpp core. It contains four Go channels, one for sending the requests
// to VPP, one for receiving the replies from it and the same set for notifications. The user can access the Go channels
// via methods provided by Channel interface in this package. Do not use the same channel from multiple goroutines
// concurrently, otherwise the responses could mix! Use multiple channels instead.
-type channel struct {
- id uint16 // channel ID
+type Channel struct {
+ id uint16
+ conn *Connection
reqChan chan *vppRequest // channel for sending the requests to VPP
replyChan chan *vppReply // channel where VPP replies are delivered to
- notifSubsChan chan *subscriptionRequest // channel for sending notification subscribe requests
- notifSubsReplyChan chan error // channel where replies to notification subscribe requests are delivered to
-
- msgDecoder api.MessageDecoder // used to decode binary data to generated API messages
- msgIdentifier api.MessageIdentifier // used to retrieve message ID of a message
+ msgCodec MessageCodec // used to decode binary data to generated API messages
+ msgIdentifier MessageIdentifier // used to retrieve message ID of a message
lastSeqNum uint16 // sequence number of the last sent request
replyTimeout time.Duration // maximum time that the API waits for a reply from VPP before returning an error, can be set with SetReplyTimeout
}
-func (ch *channel) GetID() uint16 {
+func newChannel(id uint16, conn *Connection, codec MessageCodec, identifier MessageIdentifier, reqSize, replySize int) *Channel {
+ return &Channel{
+ id: id,
+ conn: conn,
+ msgCodec: codec,
+ msgIdentifier: identifier,
+ reqChan: make(chan *vppRequest, reqSize),
+ replyChan: make(chan *vppReply, replySize),
+ replyTimeout: DefaultReplyTimeout,
+ }
+}
+
+func (ch *Channel) GetID() uint16 {
return ch.id
}
-func (ch *channel) nextSeqNum() uint16 {
+func (ch *Channel) nextSeqNum() uint16 {
ch.lastSeqNum++
return ch.lastSeqNum
}
-func (ch *channel) SendRequest(msg api.Message) api.RequestCtx {
- req := &vppRequest{
+func (ch *Channel) SendRequest(msg api.Message) api.RequestCtx {
+ seqNum := ch.nextSeqNum()
+ ch.reqChan <- &vppRequest{
msg: msg,
- seqNum: ch.nextSeqNum(),
+ seqNum: seqNum,
}
- ch.reqChan <- req
- return &requestCtx{ch: ch, seqNum: req.seqNum}
+ return &requestCtx{ch: ch, seqNum: seqNum}
}
-func (ch *channel) SendMultiRequest(msg api.Message) api.MultiRequestCtx {
- req := &vppRequest{
+func (ch *Channel) SendMultiRequest(msg api.Message) api.MultiRequestCtx {
+ seqNum := ch.nextSeqNum()
+ ch.reqChan <- &vppRequest{
msg: msg,
- seqNum: ch.nextSeqNum(),
+ seqNum: seqNum,
multi: true,
}
- ch.reqChan <- req
- return &multiRequestCtx{ch: ch, seqNum: req.seqNum}
+ return &multiRequestCtx{ch: ch, seqNum: seqNum}
}
-func (ch *channel) SubscribeNotification(notifChan chan api.Message, msgFactory func() api.Message) (*api.NotifSubscription, error) {
- sub := &api.NotifSubscription{
- NotifChan: notifChan,
- MsgFactory: msgFactory,
+func (ch *Channel) CheckCompatiblity(msgs ...api.Message) error {
+ var comperr api.CompatibilityError
+ for _, msg := range msgs {
+ _, err := ch.msgIdentifier.GetMessageID(msg)
+ if err != nil {
+ if uerr, ok := err.(*adapter.UnknownMsgError); ok {
+ m := fmt.Sprintf("%s_%s", uerr.MsgName, uerr.MsgCrc)
+ comperr.IncompatibleMessages = append(comperr.IncompatibleMessages, m)
+ continue
+ }
+ // other errors return immediatelly
+ return err
+ }
}
- // TODO: get rid of notifSubsChan and notfSubsReplyChan,
- // it's no longer need because we know all message IDs and can store subscription right here
- ch.notifSubsChan <- &subscriptionRequest{
- sub: sub,
- subscribe: true,
+ if len(comperr.IncompatibleMessages) == 0 {
+ return nil
}
- return sub, <-ch.notifSubsReplyChan
+ return &comperr
}
-func (ch *channel) UnsubscribeNotification(subscription *api.NotifSubscription) error {
- ch.notifSubsChan <- &subscriptionRequest{
- sub: subscription,
- subscribe: false,
+func (ch *Channel) SubscribeNotification(notifChan chan api.Message, event api.Message) (api.SubscriptionCtx, error) {
+ msgID, err := ch.msgIdentifier.GetMessageID(event)
+ if err != nil {
+ log.WithFields(logrus.Fields{
+ "msg_name": event.GetMessageName(),
+ "msg_crc": event.GetCrcString(),
+ }).Errorf("unable to retrieve message ID: %v", err)
+ return nil, fmt.Errorf("unable to retrieve event message ID: %v", err)
+ }
+
+ sub := &subscriptionCtx{
+ ch: ch,
+ notifChan: notifChan,
+ msgID: msgID,
+ event: event,
+ msgFactory: getMsgFactory(event),
}
- return <-ch.notifSubsReplyChan
+
+ // add the subscription into map
+ ch.conn.subscriptionsLock.Lock()
+ defer ch.conn.subscriptionsLock.Unlock()
+
+ ch.conn.subscriptions[msgID] = append(ch.conn.subscriptions[msgID], sub)
+
+ return sub, nil
}
-func (ch *channel) SetReplyTimeout(timeout time.Duration) {
+func (ch *Channel) SetReplyTimeout(timeout time.Duration) {
ch.replyTimeout = timeout
}
-func (ch *channel) Close() {
- if ch.reqChan != nil {
- close(ch.reqChan)
+func (ch *Channel) Close() {
+ close(ch.reqChan)
+}
+
+func (req *requestCtx) ReceiveReply(msg api.Message) error {
+ if req == nil || req.ch == nil {
+ return ErrInvalidRequestCtx
+ }
+
+ lastReplyReceived, err := req.ch.receiveReplyInternal(msg, req.seqNum)
+ if err != nil {
+ return err
+ } else if lastReplyReceived {
+ return errors.New("multipart reply recieved while a single reply expected")
+ }
+
+ return nil
+}
+
+func (req *multiRequestCtx) ReceiveReply(msg api.Message) (lastReplyReceived bool, err error) {
+ if req == nil || req.ch == nil {
+ return false, ErrInvalidRequestCtx
}
+
+ return req.ch.receiveReplyInternal(msg, req.seqNum)
+}
+
+func (sub *subscriptionCtx) Unsubscribe() error {
+ log.WithFields(logrus.Fields{
+ "msg_name": sub.event.GetMessageName(),
+ "msg_id": sub.msgID,
+ }).Debug("Removing notification subscription.")
+
+ // remove the subscription from the map
+ sub.ch.conn.subscriptionsLock.Lock()
+ defer sub.ch.conn.subscriptionsLock.Unlock()
+
+ for i, item := range sub.ch.conn.subscriptions[sub.msgID] {
+ if item == sub {
+ // remove i-th item in the slice
+ sub.ch.conn.subscriptions[sub.msgID] = append(sub.ch.conn.subscriptions[sub.msgID][:i], sub.ch.conn.subscriptions[sub.msgID][i+1:]...)
+ return nil
+ }
+ }
+
+ return fmt.Errorf("subscription for %q not found", sub.event.GetMessageName())
}
// receiveReplyInternal receives a reply from the reply channel into the provided msg structure.
-func (ch *channel) receiveReplyInternal(msg api.Message, expSeqNum uint16) (lastReplyReceived bool, err error) {
- var ignore bool
+func (ch *Channel) receiveReplyInternal(msg api.Message, expSeqNum uint16) (lastReplyReceived bool, err error) {
if msg == nil {
return false, errors.New("nil message passed in")
}
+ var ignore bool
+
if vppReply := ch.delayedReply; vppReply != nil {
// try the delayed reply
ch.delayedReply = nil
case vppReply := <-ch.replyChan:
ignore, lastReplyReceived, err = ch.processReply(vppReply, expSeqNum, msg)
if ignore {
+ log.WithFields(logrus.Fields{
+ "expSeqNum": expSeqNum,
+ "channel": ch.id,
+ }).Warnf("ignoring received reply: %+v (expecting: %s)", vppReply, msg.GetMessageName())
continue
}
return lastReplyReceived, err
case <-timer.C:
+ log.WithFields(logrus.Fields{
+ "expSeqNum": expSeqNum,
+ "channel": ch.id,
+ }).Debugf("timeout (%v) waiting for reply: %s", ch.replyTimeout, msg.GetMessageName())
err = fmt.Errorf("no reply received within the timeout period %s", ch.replyTimeout)
return false, err
}
}
- return
}
-func (ch *channel) processReply(reply *vppReply, expSeqNum uint16, msg api.Message) (ignore bool, lastReplyReceived bool, err error) {
+func (ch *Channel) processReply(reply *vppReply, expSeqNum uint16, msg api.Message) (ignore bool, lastReplyReceived bool, err error) {
// check the sequence number
cmpSeqNums := compareSeqNumbers(reply.seqNum, expSeqNum)
if cmpSeqNums == -1 {
// reply received too late, ignore the message
- logrus.WithField("sequence-number", reply.seqNum).Warn(
- "Received reply to an already closed binary API request")
+ log.WithField("seqNum", reply.seqNum).
+ Warn("Received reply to an already closed binary API request")
ignore = true
return
}
}
// decode the message
- if err = ch.msgDecoder.DecodeMsg(reply.data, msg); err != nil {
+ if err = ch.msgCodec.DecodeMsg(reply.data, msg); err != nil {
return
}