1 // Copyright (c) 2017 Cisco and/or its affiliates.
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at:
7 // http://www.apache.org/licenses/LICENSE-2.0
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
22 logger "github.com/sirupsen/logrus"
24 "git.fd.io/govpp.git/api"
27 // watchRequests watches for requests on the request API channel and forwards them as messages to VPP.
28 func (c *Connection) watchRequests(ch *api.Channel, chMeta *channelMetadata) {
31 case req, ok := <-ch.ReqChan:
32 // new request on the request channel
34 // after closing the request channel, release API channel and return
35 c.releaseAPIChannel(ch, chMeta)
38 c.processRequest(ch, chMeta, req)
40 case req := <-ch.NotifSubsChan:
41 // new request on the notification subscribe channel
42 c.processNotifSubscribeRequest(ch, req)
47 // processRequest processes a single request received on the request channel.
48 func (c *Connection) processRequest(ch *api.Channel, chMeta *channelMetadata, req *api.VppRequest) error {
49 // check whether we are connected to VPP
50 if atomic.LoadUint32(&c.connected) == 0 {
51 err := errors.New("not connected to VPP, ignoring the request")
53 sendReply(ch, &api.VppReply{Error: err})
57 // retrieve message ID
58 msgID, err := c.GetMessageID(req.Message)
60 err = fmt.Errorf("unable to retrieve message ID: %v", err)
61 log.WithFields(logger.Fields{
62 "msg_name": req.Message.GetMessageName(),
63 "msg_crc": req.Message.GetCrcString(),
65 sendReply(ch, &api.VppReply{Error: err})
69 // encode the message into binary
70 data, err := c.codec.EncodeMsg(req.Message, msgID)
72 err = fmt.Errorf("unable to encode the messge: %v", err)
73 log.WithFields(logger.Fields{
77 sendReply(ch, &api.VppReply{Error: err})
81 if log.Level == logger.DebugLevel { // for performance reasons - logrus does some processing even if debugs are disabled
82 log.WithFields(logger.Fields{
85 "msg_size": len(data),
86 "msg_name": req.Message.GetMessageName(),
87 }).Debug("Sending a message to VPP.")
92 // expect multipart response
93 atomic.StoreUint32(&chMeta.multipart, 1)
96 // send the request to VPP
97 c.vpp.SendMsg(chMeta.id, data)
100 // send a control ping to determine end of the multipart response
101 pingData, _ := c.codec.EncodeMsg(msgControlPing, c.pingReqID)
103 log.WithFields(logger.Fields{
104 "context": chMeta.id,
105 "msg_id": c.pingReqID,
106 "msg_size": len(pingData),
107 }).Debug("Sending a control ping to VPP.")
109 c.vpp.SendMsg(chMeta.id, pingData)
115 // msgCallback is called whenever any binary API message comes from VPP.
116 func msgCallback(context uint32, msgID uint16, data []byte) {
118 defer connLock.RUnlock()
121 log.Warn("Already disconnected, ignoring the message.")
125 if log.Level == logger.DebugLevel { // for performance reasons - logrus does some processing even if debugs are disabled
126 log.WithFields(logger.Fields{
129 "msg_size": len(data),
130 }).Debug("Received a message from VPP.")
133 if context == 0 || conn.isNotificationMessage(msgID) {
134 // process the message as a notification
135 conn.sendNotifications(msgID, data)
139 // match ch according to the context
140 conn.channelsLock.RLock()
141 ch, ok := conn.channels[context]
142 conn.channelsLock.RUnlock()
145 log.WithFields(logger.Fields{
148 }).Error("Context ID not known, ignoring the message.")
152 chMeta := ch.Metadata().(*channelMetadata)
153 lastReplyReceived := false
154 // if this is a control ping reply and multipart request is being processed, treat this as a last part of the reply
155 if msgID == conn.pingReplyID && atomic.CompareAndSwapUint32(&chMeta.multipart, 1, 0) {
156 lastReplyReceived = true
159 // send the data to the channel
160 sendReply(ch, &api.VppReply{
163 LastReplyReceived: lastReplyReceived,
167 // sendReply sends the reply into the go channel, if it cannot be completed without blocking, otherwise
168 // it logs the error and do not send the message.
169 func sendReply(ch *api.Channel, reply *api.VppReply) {
171 case ch.ReplyChan <- reply:
172 // reply sent successfully
174 // unable to write into the channel without blocking
175 log.WithFields(logger.Fields{
177 "msg_id": reply.MessageID,
178 }).Warn("Unable to send the reply, reciever end not ready.")
182 // GetMessageID returns message identifier of given API message.
183 func (c *Connection) GetMessageID(msg api.Message) (uint16, error) {
185 return 0, errors.New("nil connection passed in")
187 return c.messageNameToID(msg.GetMessageName(), msg.GetCrcString())
190 // messageNameToID returns message ID of a message identified by its name and CRC.
191 func (c *Connection) messageNameToID(msgName string, msgCrc string) (uint16, error) {
192 // try to get the ID from the map
194 id, ok := c.msgIDs[msgName+msgCrc]
195 c.msgIDsLock.RUnlock()
200 // get the ID using VPP API
201 id, err := c.vpp.GetMsgID(msgName, msgCrc)
203 err = fmt.Errorf("unable to retrieve message ID: %v", err)
204 log.WithFields(logger.Fields{
212 c.msgIDs[msgName+msgCrc] = id
213 c.msgIDsLock.Unlock()