Golang DCSpecificRequest.AllowStale方法代码示例

func TestCatalogListServices_Stale(t *testing.T) {
	dir1, s1 := testServer(t)
	defer os.RemoveAll(dir1)
	defer s1.Shutdown()
	client := rpcClient(t, s1)
	defer client.Close()

	args := structs.DCSpecificRequest{
		Datacenter: "dc1",
	}
	args.AllowStale = true
	var out structs.IndexedServices

	// Inject a fake service
	s1.fsm.State().EnsureNode(1, structs.Node{"foo", "127.0.0.1"})
	s1.fsm.State().EnsureService(2, "foo", &structs.NodeService{"db", "db", []string{"primary"}, "127.0.0.1", 5000})

	// Run the query, do not wait for leader!
	if err := client.Call("Catalog.ListServices", &args, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	// Should find the service
	if len(out.Services) != 1 {
		t.Fatalf("bad: %v", out)
	}

	// Should not have a leader! Stale read
	if out.KnownLeader {
		t.Fatalf("bad: %v", out)
	}
}

// UINodes is used to list the nodes in a given datacenter. We return a
// NodeDump which provides overview information for all the nodes
func (s *HTTPServer) UINodes(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
	// Parse arguments
	args := structs.DCSpecificRequest{}
	if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
		return nil, nil
	}

	// Make the RPC request
	var out structs.IndexedNodeDump
	defer setMeta(resp, &out.QueryMeta)
RPC:
	if err := s.agent.RPC("Internal.NodeDump", &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
	}

	// Use empty list instead of nil
	for _, info := range out.Dump {
		if info.Services == nil {
			info.Services = make([]*structs.NodeService, 0)
		}
		if info.Checks == nil {
			info.Checks = make([]*structs.HealthCheck, 0)
		}
	}
	if out.Dump == nil {
		out.Dump = make(structs.NodeDump, 0)
	}
	return out.Dump, nil
}

// ReplicationStatus is used to retrieve the current ACL replication status.
func (a *ACL) ReplicationStatus(args *structs.DCSpecificRequest,
	reply *structs.ACLReplicationStatus) error {
	// This must be sent to the leader, so we fix the args since we are
	// re-using a structure where we don't support all the options.
	args.RequireConsistent = true
	args.AllowStale = false
	if done, err := a.srv.forward("ACL.ReplicationStatus", args, args, reply); done {
		return err
	}

	// There's no ACL token required here since this doesn't leak any
	// sensitive information, and we don't want people to have to use
	// management tokens if they are querying this via a health check.

	// Poll the latest status.
	a.srv.aclReplicationStatusLock.RLock()
	*reply = a.srv.aclReplicationStatus
	a.srv.aclReplicationStatusLock.RUnlock()
	return nil
}

// UINodes is used to list the nodes in a given datacenter. We return a
// NodeDump which provides overview information for all the nodes
func (s *HTTPServer) UINodes(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
	// Parse arguments
	args := structs.DCSpecificRequest{}
	if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
		return nil, nil
	}

	// Make the RPC request
	var out structs.IndexedNodeDump
	defer setMeta(resp, &out.QueryMeta)
RPC:
	if err := s.agent.RPC("Internal.NodeDump", &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 out.Dump, nil
}