mirror of
https://github.com/juanfont/headscale.git
synced 2024-12-24 21:25:52 -05:00
669 lines
18 KiB
Go
669 lines
18 KiB
Go
package headscale
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import (
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"context"
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"fmt"
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"net/http"
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"time"
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"github.com/rs/zerolog/log"
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"tailscale.com/tailcfg"
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)
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const (
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keepAliveInterval = 60 * time.Second
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)
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type contextKey string
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const machineNameContextKey = contextKey("machineName")
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func (h *Headscale) handlePollCommon(
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writer http.ResponseWriter,
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req *http.Request,
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machine *Machine,
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mapRequest tailcfg.MapRequest,
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isNoise bool,
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) {
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machine.Hostname = mapRequest.Hostinfo.Hostname
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machine.HostInfo = HostInfo(*mapRequest.Hostinfo)
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machine.DiscoKey = DiscoPublicKeyStripPrefix(mapRequest.DiscoKey)
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now := time.Now().UTC()
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// update ACLRules with peer informations (to update server tags if necessary)
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if h.aclPolicy != nil {
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err := h.UpdateACLRules()
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if err != nil {
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log.Error().
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Caller().
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Bool("noise", isNoise).
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Str("func", "handleAuthKey").
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Str("machine", machine.Hostname).
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Err(err)
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}
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}
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// From Tailscale client:
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//
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// ReadOnly is whether the client just wants to fetch the MapResponse,
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// without updating their Endpoints. The Endpoints field will be ignored and
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// LastSeen will not be updated and peers will not be notified of changes.
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//
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// The intended use is for clients to discover the DERP map at start-up
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// before their first real endpoint update.
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if !mapRequest.ReadOnly {
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machine.Endpoints = mapRequest.Endpoints
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machine.LastSeen = &now
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}
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if err := h.db.Updates(machine).Error; err != nil {
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if err != nil {
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log.Error().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("node_key", machine.NodeKey).
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Str("machine", machine.Hostname).
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Err(err).
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Msg("Failed to persist/update machine in the database")
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http.Error(writer, "", http.StatusInternalServerError)
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return
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}
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}
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mapResp, err := h.getMapResponseData(mapRequest, machine, isNoise)
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if err != nil {
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log.Error().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("node_key", machine.NodeKey).
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Str("machine", machine.Hostname).
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Err(err).
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Msg("Failed to get Map response")
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http.Error(writer, "", http.StatusInternalServerError)
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return
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}
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// We update our peers if the client is not sending ReadOnly in the MapRequest
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// so we don't distribute its initial request (it comes with
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// empty endpoints to peers)
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// Details on the protocol can be found in https://github.com/tailscale/tailscale/blob/main/tailcfg/tailcfg.go#L696
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log.Debug().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Bool("readOnly", mapRequest.ReadOnly).
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Bool("omitPeers", mapRequest.OmitPeers).
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Bool("stream", mapRequest.Stream).
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Msg("Client map request processed")
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if mapRequest.ReadOnly {
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log.Info().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msg("Client is starting up. Probably interested in a DERP map")
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writer.Header().Set("Content-Type", "application/json; charset=utf-8")
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writer.WriteHeader(http.StatusOK)
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_, err := writer.Write(mapResp)
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if err != nil {
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log.Error().
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Caller().
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Err(err).
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Msg("Failed to write response")
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}
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if f, ok := writer.(http.Flusher); ok {
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f.Flush()
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}
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return
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}
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// There has been an update to _any_ of the nodes that the other nodes would
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// need to know about
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h.setLastStateChangeToNow(machine.Namespace.Name)
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// The request is not ReadOnly, so we need to set up channels for updating
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// peers via longpoll
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// Only create update channel if it has not been created
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log.Trace().
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Caller().
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msg("Loading or creating update channel")
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const chanSize = 8
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updateChan := make(chan struct{}, chanSize)
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pollDataChan := make(chan []byte, chanSize)
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defer closeChanWithLog(pollDataChan, machine.Hostname, "pollDataChan")
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keepAliveChan := make(chan []byte)
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if mapRequest.OmitPeers && !mapRequest.Stream {
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log.Info().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msg("Client sent endpoint update and is ok with a response without peer list")
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writer.Header().Set("Content-Type", "application/json; charset=utf-8")
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writer.WriteHeader(http.StatusOK)
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_, err := writer.Write(mapResp)
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if err != nil {
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log.Error().
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Caller().
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Err(err).
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Msg("Failed to write response")
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}
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// It sounds like we should update the nodes when we have received a endpoint update
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// even tho the comments in the tailscale code dont explicitly say so.
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updateRequestsFromNode.WithLabelValues(machine.Namespace.Name, machine.Hostname, "endpoint-update").
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Inc()
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updateChan <- struct{}{}
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return
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} else if mapRequest.OmitPeers && mapRequest.Stream {
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log.Warn().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msg("Ignoring request, don't know how to handle it")
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http.Error(writer, "", http.StatusBadRequest)
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return
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}
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log.Info().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msg("Client is ready to access the tailnet")
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log.Info().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msg("Sending initial map")
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pollDataChan <- mapResp
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log.Info().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msg("Notifying peers")
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updateRequestsFromNode.WithLabelValues(machine.Namespace.Name, machine.Hostname, "full-update").
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Inc()
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updateChan <- struct{}{}
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h.pollNetMapStream(
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writer,
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req,
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machine,
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mapRequest,
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pollDataChan,
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keepAliveChan,
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updateChan,
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isNoise,
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)
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log.Trace().
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Str("handler", "PollNetMap").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msg("Finished stream, closing PollNetMap session")
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}
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// pollNetMapStream stream logic for /machine/map,
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// ensuring we communicate updates and data to the connected clients.
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func (h *Headscale) pollNetMapStream(
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writer http.ResponseWriter,
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req *http.Request,
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machine *Machine,
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mapRequest tailcfg.MapRequest,
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pollDataChan chan []byte,
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keepAliveChan chan []byte,
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updateChan chan struct{},
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isNoise bool,
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) {
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h.pollNetMapStreamWG.Add(1)
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defer h.pollNetMapStreamWG.Done()
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ctx := context.WithValue(req.Context(), machineNameContextKey, machine.Hostname)
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ctx, cancel := context.WithCancel(ctx)
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defer cancel()
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go h.scheduledPollWorker(
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ctx,
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updateChan,
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keepAliveChan,
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mapRequest,
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machine,
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isNoise,
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)
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log.Trace().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msg("Waiting for data to stream...")
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log.Trace().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Msgf("pollData is %#v, keepAliveChan is %#v, updateChan is %#v", pollDataChan, keepAliveChan, updateChan)
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for {
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select {
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case data := <-pollDataChan:
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log.Trace().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "pollData").
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Int("bytes", len(data)).
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Msg("Sending data received via pollData channel")
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_, err := writer.Write(data)
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if err != nil {
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log.Error().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "pollData").
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Err(err).
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Msg("Cannot write data")
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return
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}
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flusher, ok := writer.(http.Flusher)
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if !ok {
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log.Error().
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Caller().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "pollData").
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Msg("Cannot cast writer to http.Flusher")
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} else {
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flusher.Flush()
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}
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log.Trace().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "pollData").
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Int("bytes", len(data)).
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Msg("Data from pollData channel written successfully")
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// TODO(kradalby): Abstract away all the database calls, this can cause race conditions
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// when an outdated machine object is kept alive, e.g. db is update from
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// command line, but then overwritten.
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err = h.UpdateMachineFromDatabase(machine)
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if err != nil {
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log.Error().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "pollData").
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Err(err).
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Msg("Cannot update machine from database")
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// client has been removed from database
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// since the stream opened, terminate connection.
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return
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}
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now := time.Now().UTC()
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machine.LastSeen = &now
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lastStateUpdate.WithLabelValues(machine.Namespace.Name, machine.Hostname).
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Set(float64(now.Unix()))
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machine.LastSuccessfulUpdate = &now
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err = h.TouchMachine(machine)
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if err != nil {
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log.Error().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "pollData").
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Err(err).
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Msg("Cannot update machine LastSuccessfulUpdate")
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return
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}
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log.Trace().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "pollData").
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Int("bytes", len(data)).
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Msg("Machine entry in database updated successfully after sending data")
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case data := <-keepAliveChan:
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log.Trace().
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Str("handler", "PollNetMapStream").
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Str("machine", machine.Hostname).
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Str("channel", "keepAlive").
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Int("bytes", len(data)).
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Msg("Sending keep alive message")
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_, err := writer.Write(data)
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if err != nil {
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log.Error().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "keepAlive").
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Err(err).
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Msg("Cannot write keep alive message")
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return
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}
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flusher, ok := writer.(http.Flusher)
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if !ok {
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log.Error().
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Caller().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "keepAlive").
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Msg("Cannot cast writer to http.Flusher")
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} else {
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flusher.Flush()
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}
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log.Trace().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "keepAlive").
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Int("bytes", len(data)).
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Msg("Keep alive sent successfully")
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// TODO(kradalby): Abstract away all the database calls, this can cause race conditions
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// when an outdated machine object is kept alive, e.g. db is update from
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// command line, but then overwritten.
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err = h.UpdateMachineFromDatabase(machine)
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if err != nil {
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log.Error().
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
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Str("machine", machine.Hostname).
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Str("channel", "keepAlive").
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Err(err).
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Msg("Cannot update machine from database")
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// client has been removed from database
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// since the stream opened, terminate connection.
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return
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}
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now := time.Now().UTC()
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machine.LastSeen = &now
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err = h.TouchMachine(machine)
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if err != nil {
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log.Error().
|
|
Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
|
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Str("machine", machine.Hostname).
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Str("channel", "keepAlive").
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Err(err).
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Msg("Cannot update machine LastSeen")
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return
|
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}
|
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|
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log.Trace().
|
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Str("handler", "PollNetMapStream").
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Bool("noise", isNoise).
|
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Str("machine", machine.Hostname).
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Str("channel", "keepAlive").
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Int("bytes", len(data)).
|
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Msg("Machine updated successfully after sending keep alive")
|
|
|
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case <-updateChan:
|
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log.Trace().
|
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Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
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Str("machine", machine.Hostname).
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Str("channel", "update").
|
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Msg("Received a request for update")
|
|
updateRequestsReceivedOnChannel.WithLabelValues(machine.Namespace.Name, machine.Hostname).
|
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Inc()
|
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|
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if h.isOutdated(machine) {
|
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var lastUpdate time.Time
|
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if machine.LastSuccessfulUpdate != nil {
|
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lastUpdate = *machine.LastSuccessfulUpdate
|
|
}
|
|
log.Debug().
|
|
Str("handler", "PollNetMapStream").
|
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Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Time("last_successful_update", lastUpdate).
|
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Time("last_state_change", h.getLastStateChange(machine.Namespace.Name)).
|
|
Msgf("There has been updates since the last successful update to %s", machine.Hostname)
|
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data, err := h.getMapResponseData(mapRequest, machine, false)
|
|
if err != nil {
|
|
log.Error().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Str("channel", "update").
|
|
Err(err).
|
|
Msg("Could not get the map update")
|
|
|
|
return
|
|
}
|
|
_, err = writer.Write(data)
|
|
if err != nil {
|
|
log.Error().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Str("channel", "update").
|
|
Err(err).
|
|
Msg("Could not write the map response")
|
|
updateRequestsSentToNode.WithLabelValues(machine.Namespace.Name, machine.Hostname, "failed").
|
|
Inc()
|
|
|
|
return
|
|
}
|
|
|
|
flusher, ok := writer.(http.Flusher)
|
|
if !ok {
|
|
log.Error().
|
|
Caller().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Str("channel", "update").
|
|
Msg("Cannot cast writer to http.Flusher")
|
|
} else {
|
|
flusher.Flush()
|
|
}
|
|
|
|
log.Trace().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Str("channel", "update").
|
|
Msg("Updated Map has been sent")
|
|
updateRequestsSentToNode.WithLabelValues(machine.Namespace.Name, machine.Hostname, "success").
|
|
Inc()
|
|
|
|
// Keep track of the last successful update,
|
|
// we sometimes end in a state were the update
|
|
// is not picked up by a client and we use this
|
|
// to determine if we should "force" an update.
|
|
// TODO(kradalby): Abstract away all the database calls, this can cause race conditions
|
|
// when an outdated machine object is kept alive, e.g. db is update from
|
|
// command line, but then overwritten.
|
|
err = h.UpdateMachineFromDatabase(machine)
|
|
if err != nil {
|
|
log.Error().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Str("channel", "update").
|
|
Err(err).
|
|
Msg("Cannot update machine from database")
|
|
|
|
// client has been removed from database
|
|
// since the stream opened, terminate connection.
|
|
return
|
|
}
|
|
now := time.Now().UTC()
|
|
|
|
lastStateUpdate.WithLabelValues(machine.Namespace.Name, machine.Hostname).
|
|
Set(float64(now.Unix()))
|
|
machine.LastSuccessfulUpdate = &now
|
|
|
|
err = h.TouchMachine(machine)
|
|
if err != nil {
|
|
log.Error().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Str("channel", "update").
|
|
Err(err).
|
|
Msg("Cannot update machine LastSuccessfulUpdate")
|
|
|
|
return
|
|
}
|
|
} else {
|
|
var lastUpdate time.Time
|
|
if machine.LastSuccessfulUpdate != nil {
|
|
lastUpdate = *machine.LastSuccessfulUpdate
|
|
}
|
|
log.Trace().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Time("last_successful_update", lastUpdate).
|
|
Time("last_state_change", h.getLastStateChange(machine.Namespace.Name)).
|
|
Msgf("%s is up to date", machine.Hostname)
|
|
}
|
|
|
|
case <-ctx.Done():
|
|
log.Info().
|
|
Str("handler", "PollNetMapStream").
|
|
Str("machine", machine.Hostname).
|
|
Msg("The client has closed the connection")
|
|
// TODO: Abstract away all the database calls, this can cause race conditions
|
|
// when an outdated machine object is kept alive, e.g. db is update from
|
|
// command line, but then overwritten.
|
|
err := h.UpdateMachineFromDatabase(machine)
|
|
if err != nil {
|
|
log.Error().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Str("channel", "Done").
|
|
Err(err).
|
|
Msg("Cannot update machine from database")
|
|
|
|
// client has been removed from database
|
|
// since the stream opened, terminate connection.
|
|
return
|
|
}
|
|
now := time.Now().UTC()
|
|
machine.LastSeen = &now
|
|
err = h.TouchMachine(machine)
|
|
if err != nil {
|
|
log.Error().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Str("channel", "Done").
|
|
Err(err).
|
|
Msg("Cannot update machine LastSeen")
|
|
}
|
|
|
|
// The connection has been closed, so we can stop polling.
|
|
return
|
|
|
|
case <-h.shutdownChan:
|
|
log.Info().
|
|
Str("handler", "PollNetMapStream").
|
|
Bool("noise", isNoise).
|
|
Str("machine", machine.Hostname).
|
|
Msg("The long-poll handler is shutting down")
|
|
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
func (h *Headscale) scheduledPollWorker(
|
|
ctx context.Context,
|
|
updateChan chan struct{},
|
|
keepAliveChan chan []byte,
|
|
mapRequest tailcfg.MapRequest,
|
|
machine *Machine,
|
|
isNoise bool,
|
|
) {
|
|
keepAliveTicker := time.NewTicker(keepAliveInterval)
|
|
updateCheckerTicker := time.NewTicker(h.cfg.NodeUpdateCheckInterval)
|
|
|
|
defer closeChanWithLog(
|
|
updateChan,
|
|
fmt.Sprint(ctx.Value(machineNameContextKey)),
|
|
"updateChan",
|
|
)
|
|
defer closeChanWithLog(
|
|
keepAliveChan,
|
|
fmt.Sprint(ctx.Value(machineNameContextKey)),
|
|
"updateChan",
|
|
)
|
|
|
|
for {
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
|
|
case <-keepAliveTicker.C:
|
|
data, err := h.getMapKeepAliveResponseData(mapRequest, machine, isNoise)
|
|
if err != nil {
|
|
log.Error().
|
|
Str("func", "keepAlive").
|
|
Bool("noise", isNoise).
|
|
Err(err).
|
|
Msg("Error generating the keep alive msg")
|
|
|
|
return
|
|
}
|
|
|
|
log.Debug().
|
|
Str("func", "keepAlive").
|
|
Str("machine", machine.Hostname).
|
|
Bool("noise", isNoise).
|
|
Msg("Sending keepalive")
|
|
keepAliveChan <- data
|
|
|
|
case <-updateCheckerTicker.C:
|
|
log.Debug().
|
|
Str("func", "scheduledPollWorker").
|
|
Str("machine", machine.Hostname).
|
|
Bool("noise", isNoise).
|
|
Msg("Sending update request")
|
|
updateRequestsFromNode.WithLabelValues(machine.Namespace.Name, machine.Hostname, "scheduled-update").
|
|
Inc()
|
|
updateChan <- struct{}{}
|
|
}
|
|
}
|
|
}
|
|
|
|
func closeChanWithLog[C chan []byte | chan struct{}](channel C, machine, name string) {
|
|
log.Trace().
|
|
Str("handler", "PollNetMap").
|
|
Str("machine", machine).
|
|
Str("channel", "Done").
|
|
Msg(fmt.Sprintf("Closing %s channel", name))
|
|
|
|
close(channel)
|
|
}
|