// 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
}
// UIServices is used to list the services in a given datacenter. We return a
// ServiceSummary which provides overview information for the service
func (s *HTTPServer) UIServices(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
}
// Generate the summary
return summarizeServices(out.Dump), nil
}
func TestCatalogListServices_Stale(t *testing.T) {
dir1, s1 := testServer(t)
defer os.RemoveAll(dir1)
defer s1.Shutdown()
codec := rpcClient(t, s1)
defer codec.Close()
args := structs.DCSpecificRequest{
Datacenter: "dc1",
}
args.AllowStale = true
var out structs.IndexedServices
// Inject a fake service
if err := s1.fsm.State().EnsureNode(1, &structs.Node{Node: "foo", Address: "127.0.0.1"}); err != nil {
t.Fatalf("err: %v", err)
}
if err := s1.fsm.State().EnsureService(2, "foo", &structs.NodeService{ID: "db", Service: "db", Tags: []string{"primary"}, Address: "127.0.0.1", Port: 5000}); err != nil {
t.Fatalf("err: %v", err)
}
// Run the query, do not wait for leader!
if err := msgpackrpc.CallWithCodec(codec, "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)
}
}