// 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 {
		return out.Dump[0], nil
	}
	return nil, nil
}

// SessionsForNode returns all the nodes belonging to a node
func (s *HTTPServer) SessionsForNode(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
	args := structs.NodeSpecificRequest{}
	if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
		return nil, nil
	}

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

	var out structs.IndexedSessions
	defer setMeta(resp, &out.QueryMeta)
	if err := s.agent.RPC("Session.NodeSessions", &args, &out); err != nil {
		return nil, err
	}

	// Use empty list instead of nil
	if out.Sessions == nil {
		out.Sessions = make(structs.Sessions, 0)
	}
	return out.Sessions, nil
}

func (s *HTTPServer) CatalogNodeServices(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
	// Set default Datacenter
	args := structs.NodeSpecificRequest{}
	if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
		return nil, nil
	}

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

	// Make the RPC request
	var out structs.IndexedNodeServices
	defer setMeta(resp, &out.QueryMeta)
	if err := s.agent.RPC("Catalog.NodeServices", &args, &out); err != nil {
		return nil, err
	}
	if out.NodeServices != nil && out.NodeServices.Node != nil {
		translateAddresses(s.agent.config, args.Datacenter, out.NodeServices.Node)
	}

	return out.NodeServices, nil
}

func (s *HTTPServer) HealthNodeChecks(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
	// Set default DC
	args := structs.NodeSpecificRequest{}
	if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
		return nil, nil
	}

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

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

	// Use empty list instead of nil
	if out.HealthChecks == nil {
		out.HealthChecks = make(structs.HealthChecks, 0)
	}
	return out.HealthChecks, nil
}

// 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 {
		if out.LastContact > d.config.MaxStale {
			args.AllowStale = false
			d.logger.Printf("[WARN] dns: Query results too stale, re-requesting")
			goto RPC
		} else if out.LastContact > staleCounterThreshold {
			metrics.IncrCounter([]string{"consul", "dns", "stale_queries"}, 1)
		}
	}

	// 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
	n := out.NodeServices.Node
	addr := translateAddress(d.agent.config, datacenter, n.Address, n.TaggedAddresses)
	records := d.formatNodeRecord(out.NodeServices.Node, addr,
		req.Question[0].Name, qType, d.config.NodeTTL)
	if records != nil {
		resp.Answer = append(resp.Answer, records...)
	}
}

// nodeLookup is used to handle a node query
func (d *DNSServer) nodeLookup(network, datacenter, node string, req, resp *dns.Msg) {
	// Only handle ANY and A type requests
	qType := req.Question[0].Qtype
	if qType != dns.TypeANY && qType != dns.TypeA {
		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 {
		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...)
	}
}

func (s *HTTPServer) HealthNodeChecks(resp http.ResponseWriter, req *http.Request) (uint64, interface{}, error) {
	// Set default DC
	args := structs.NodeSpecificRequest{}
	if done := s.parse(resp, req, &args.Datacenter, &args.BlockingQuery); done {
		return 0, nil, nil
	}

	// Pull out the service name
	args.Node = strings.TrimPrefix(req.URL.Path, "/v1/health/node/")
	if args.Node == "" {
		resp.WriteHeader(400)
		resp.Write([]byte("Missing node name"))
		return 0, nil, nil
	}

	// Make the RPC request
	var out structs.IndexedHealthChecks
	if err := s.agent.RPC("Health.NodeChecks", &args, &out); err != nil {
		return 0, nil, err
	}
	return out.Index, out.HealthChecks, nil
}

func TestSession_Get_List_NodeSessions_ACLFilter(t *testing.T) {
	dir1, s1 := testServerWithConfig(t, func(c *Config) {
		c.ACLDatacenter = "dc1"
		c.ACLMasterToken = "root"
		c.ACLDefaultPolicy = "deny"
		c.ACLEnforceVersion8 = false
	})
	defer os.RemoveAll(dir1)
	defer s1.Shutdown()
	codec := rpcClient(t, s1)
	defer codec.Close()

	testutil.WaitForLeader(t, s1.RPC, "dc1")

	// Create the ACL.
	req := structs.ACLRequest{
		Datacenter: "dc1",
		Op:         structs.ACLSet,
		ACL: structs.ACL{
			Name: "User token",
			Type: structs.ACLTypeClient,
			Rules: `
session "foo" {
	policy = "read"
}
`,
		},
		WriteRequest: structs.WriteRequest{Token: "root"},
	}

	var token string
	if err := msgpackrpc.CallWithCodec(codec, "ACL.Apply", &req, &token); err != nil {
		t.Fatalf("err: %v", err)
	}

	// Create a node and a session.
	s1.fsm.State().EnsureNode(1, &structs.Node{Node: "foo", Address: "127.0.0.1"})
	arg := structs.SessionRequest{
		Datacenter: "dc1",
		Op:         structs.SessionCreate,
		Session: structs.Session{
			Node: "foo",
		},
		WriteRequest: structs.WriteRequest{Token: "root"},
	}
	var out string
	if err := msgpackrpc.CallWithCodec(codec, "Session.Apply", &arg, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	// Perform all the read operations, which should go through since version
	// 8 ACL enforcement isn't enabled.
	getR := structs.SessionSpecificRequest{
		Datacenter: "dc1",
		Session:    out,
	}
	{
		var sessions structs.IndexedSessions
		if err := msgpackrpc.CallWithCodec(codec, "Session.Get", &getR, &sessions); err != nil {
			t.Fatalf("err: %v", err)
		}
		if len(sessions.Sessions) != 1 {
			t.Fatalf("bad: %v", sessions.Sessions)
		}
	}
	listR := structs.DCSpecificRequest{
		Datacenter: "dc1",
	}
	{
		var sessions structs.IndexedSessions
		if err := msgpackrpc.CallWithCodec(codec, "Session.List", &listR, &sessions); err != nil {
			t.Fatalf("err: %v", err)
		}
		if len(sessions.Sessions) != 1 {
			t.Fatalf("bad: %v", sessions.Sessions)
		}
	}
	nodeR := structs.NodeSpecificRequest{
		Datacenter: "dc1",
		Node:       "foo",
	}
	{
		var sessions structs.IndexedSessions
		if err := msgpackrpc.CallWithCodec(codec, "Session.NodeSessions", &nodeR, &sessions); err != nil {
			t.Fatalf("err: %v", err)
		}
		if len(sessions.Sessions) != 1 {
			t.Fatalf("bad: %v", sessions.Sessions)
		}
	}

	// Now turn on version 8 enforcement and make sure everything is empty.
	s1.config.ACLEnforceVersion8 = true
	{
		var sessions structs.IndexedSessions
		if err := msgpackrpc.CallWithCodec(codec, "Session.Get", &getR, &sessions); err != nil {
			t.Fatalf("err: %v", err)
		}
		if len(sessions.Sessions) != 0 {
			t.Fatalf("bad: %v", sessions.Sessions)
//.........这里部分代码省略.........

func TestCatalog_NodeServices_ACLDeny(t *testing.T) {
	dir1, s1 := testServerWithConfig(t, func(c *Config) {
		c.ACLDatacenter = "dc1"
		c.ACLMasterToken = "root"
		c.ACLDefaultPolicy = "deny"
		c.ACLEnforceVersion8 = false
	})
	defer os.RemoveAll(dir1)
	defer s1.Shutdown()
	codec := rpcClient(t, s1)
	defer codec.Close()

	testutil.WaitForLeader(t, s1.RPC, "dc1")

	// Prior to version 8, the node policy should be ignored.
	args := structs.NodeSpecificRequest{
		Datacenter: "dc1",
		Node:       s1.config.NodeName,
	}
	reply := structs.IndexedNodeServices{}
	if err := msgpackrpc.CallWithCodec(codec, "Catalog.NodeServices", &args, &reply); err != nil {
		t.Fatalf("err: %v", err)
	}
	if reply.NodeServices == nil {
		t.Fatalf("should not be nil")
	}

	// Now turn on version 8 enforcement and try again.
	s1.config.ACLEnforceVersion8 = true
	if err := msgpackrpc.CallWithCodec(codec, "Catalog.NodeServices", &args, &reply); err != nil {
		t.Fatalf("err: %v", err)
	}
	if reply.NodeServices != nil {
		t.Fatalf("should not nil")
	}

	// Create an ACL that can read the node.
	arg := structs.ACLRequest{
		Datacenter: "dc1",
		Op:         structs.ACLSet,
		ACL: structs.ACL{
			Name: "User token",
			Type: structs.ACLTypeClient,
			Rules: fmt.Sprintf(`
node "%s" {
	policy = "read"
}
`, s1.config.NodeName),
		},
		WriteRequest: structs.WriteRequest{Token: "root"},
	}
	var id string
	if err := msgpackrpc.CallWithCodec(codec, "ACL.Apply", &arg, &id); err != nil {
		t.Fatalf("err: %v", err)
	}

	// Now try with the token and it will go through.
	args.Token = id
	if err := msgpackrpc.CallWithCodec(codec, "Catalog.NodeServices", &args, &reply); err != nil {
		t.Fatalf("err: %v", err)
	}
	if reply.NodeServices == nil {
		t.Fatalf("should not be nil")
	}

	// Make sure an unknown node doesn't cause trouble.
	args.Node = "nope"
	if err := msgpackrpc.CallWithCodec(codec, "Catalog.NodeServices", &args, &reply); err != nil {
		t.Fatalf("err: %v", err)
	}
	if reply.NodeServices != nil {
		t.Fatalf("should not nil")
	}
}