Ejemplo n.º 1
0
func (s *HTTPServer) HealthServiceNodes(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
	// Set default DC
	args := structs.ServiceSpecificRequest{}
	s.parseSource(req, &args.Source)
	if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
		return nil, nil
	}

	// Check for a tag
	params := req.URL.Query()
	if _, ok := params["tag"]; ok {
		args.ServiceTag = params.Get("tag")
		args.TagFilter = true
	}

	// Pull out the service name
	args.ServiceName = strings.TrimPrefix(req.URL.Path, "/v1/health/service/")
	if args.ServiceName == "" {
		resp.WriteHeader(400)
		resp.Write([]byte("Missing service name"))
		return nil, nil
	}

	// Make the RPC request
	var out structs.IndexedCheckServiceNodes
	defer setMeta(resp, &out.QueryMeta)
	if err := s.agent.RPC("Health.ServiceNodes", &args, &out); err != nil {
		return nil, err
	}

	// Filter to only passing if specified
	if _, ok := params["passing"]; ok {
		out.Nodes = filterNonPassing(out.Nodes)
	}

	// Use empty list instead of nil
	for i, _ := range out.Nodes {
		// TODO (slackpad) It's lame that this isn't a slice of pointers
		// but it's not a well-scoped change to fix this. We should
		// change this at the next opportunity.
		if out.Nodes[i].Checks == nil {
			out.Nodes[i].Checks = make(structs.HealthChecks, 0)
		}
	}
	if out.Nodes == nil {
		out.Nodes = make(structs.CheckServiceNodes, 0)
	}
	return out.Nodes, nil
}
Ejemplo n.º 2
0
// serviceLookup is used to handle a service query
func (d *DNSServer) serviceLookup(network, datacenter, service, tag string, req, resp *dns.Msg) {
	// Make an RPC request
	args := structs.ServiceSpecificRequest{
		Datacenter:  datacenter,
		ServiceName: service,
		ServiceTag:  tag,
		TagFilter:   tag != "",
		QueryOptions: structs.QueryOptions{
			Token:      d.agent.config.ACLToken,
			AllowStale: d.config.AllowStale,
		},
	}
	var out structs.IndexedCheckServiceNodes
RPC:
	if err := d.agent.RPC("Health.ServiceNodes", &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
	}

	// Determine the TTL
	var ttl time.Duration
	if d.config.ServiceTTL != nil {
		var ok bool
		ttl, ok = d.config.ServiceTTL[service]
		if !ok {
			ttl = d.config.ServiceTTL["*"]
		}
	}

	// Filter out any service nodes due to health checks
	out.Nodes = out.Nodes.Filter(d.config.OnlyPassing)

	// If we have no nodes, return not found!
	if len(out.Nodes) == 0 {
		d.addSOA(d.domain, resp)
		resp.SetRcode(req, dns.RcodeNameError)
		return
	}

	// Perform a random shuffle
	out.Nodes.Shuffle()

	// Add various responses depending on the request
	qType := req.Question[0].Qtype
	d.serviceNodeRecords(out.Nodes, req, resp, ttl)

	if qType == dns.TypeSRV {
		d.serviceSRVRecords(datacenter, out.Nodes, req, resp, ttl)
	}

	// If the network is not TCP, restrict the number of responses
	if network != "tcp" && len(resp.Answer) > maxServiceResponses {
		resp.Answer = resp.Answer[:maxServiceResponses]

		// Flag that there are more records to return in the UDP response
		if d.config.EnableTruncate {
			resp.Truncated = true
		}
	}

	// If the answer is empty, return not found
	if len(resp.Answer) == 0 {
		d.addSOA(d.domain, resp)
		return
	}
}