// nodeLookup is used to handle a node query
func (d *DNSServer) nodeLookup(network, datacenter, node string, req, resp *dns.Msg) {
// Only handle ANY, A and AAAA type requests
qType := req.Question[0].Qtype
if qType != dns.TypeANY && qType != dns.TypeA && qType != dns.TypeAAAA {
return
}
// Make an RPC request
args := structs.NodeSpecificRequest{
Datacenter: datacenter,
Node: node,
QueryOptions: structs.QueryOptions{
Token: d.agent.config.ACLToken,
AllowStale: d.config.AllowStale,
},
}
var out structs.IndexedNodeServices
RPC:
if err := d.agent.RPC("Catalog.NodeServices", &args, &out); err != nil {
d.logger.Printf("[ERR] dns: rpc error: %v", err)
resp.SetRcode(req, dns.RcodeServerFailure)
return
}
// Verify that request is not too stale, redo the request
if args.AllowStale && out.LastContact > d.config.MaxStale {
args.AllowStale = false
d.logger.Printf("[WARN] dns: Query results too stale, re-requesting")
goto RPC
}
// If we have no address, return not found!
if out.NodeServices == nil {
d.addSOA(d.domain, resp)
resp.SetRcode(req, dns.RcodeNameError)
return
}
// Add the node record
records := d.formatNodeRecord(out.NodeServices.Node, out.NodeServices.Node.Address,
req.Question[0].Name, qType, d.config.NodeTTL)
if records != nil {
resp.Answer = append(resp.Answer, records...)
}
}
// UINodeInfo is used to get info on a single node in a given datacenter. We return a
// NodeInfo which provides overview information for the node
func (s *HTTPServer) UINodeInfo(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
// Parse arguments
args := structs.NodeSpecificRequest{}
if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
return nil, nil
}
// Verify we have some DC, or use the default
args.Node = strings.TrimPrefix(req.URL.Path, "/v1/internal/ui/node/")
if args.Node == "" {
resp.WriteHeader(400)
resp.Write([]byte("Missing node name"))
return nil, nil
}
// Make the RPC request
var out structs.IndexedNodeDump
defer setMeta(resp, &out.QueryMeta)
RPC:
if err := s.agent.RPC("Internal.NodeInfo", &args, &out); err != nil {
// Retry the request allowing stale data if no leader
if strings.Contains(err.Error(), structs.ErrNoLeader.Error()) && !args.AllowStale {
args.AllowStale = true
goto RPC
}
return nil, err
}
// Return only the first entry
if len(out.Dump) > 0 {
info := out.Dump[0]
if info.Services == nil {
info.Services = make([]*structs.NodeService, 0)
}
if info.Checks == nil {
info.Checks = make([]*structs.HealthCheck, 0)
}
return info, nil
}
return nil, nil
}