package structs import ( "encoding/json" "fmt" "reflect" "github.com/hashicorp/go-multierror" "github.com/mitchellh/copystructure" "github.com/mitchellh/mapstructure" "github.com/mitchellh/reflectwalk" ) // ServiceDefinition is used to JSON decode the Service definitions. For // documentation on specific fields see NodeService which is better documented. type ServiceDefinition struct { Kind ServiceKind `json:",omitempty"` ID string Name string Tags []string Address string Meta map[string]string Port int Check CheckType Checks CheckTypes Weights *Weights Token string EnableTagOverride bool ProxyDestination string Connect *ServiceConnect } func (s *ServiceDefinition) NodeService() *NodeService { ns := &NodeService{ Kind: s.Kind, ID: s.ID, Service: s.Name, Tags: s.Tags, Address: s.Address, Meta: s.Meta, Port: s.Port, Weights: s.Weights, EnableTagOverride: s.EnableTagOverride, ProxyDestination: s.ProxyDestination, } if s.Connect != nil { ns.Connect = *s.Connect } if ns.ID == "" && ns.Service != "" { ns.ID = ns.Service } return ns } // ConnectManagedProxy returns a ConnectManagedProxy from the ServiceDefinition // if one is configured validly. Note that is may return nil if no proxy is // configured and will also return nil error in this case too as it's an // expected case. The error returned indicates that there was an attempt to // configure a proxy made but that it was invalid input, e.g. invalid // "exec_mode". func (s *ServiceDefinition) ConnectManagedProxy() (*ConnectManagedProxy, error) { if s.Connect == nil || s.Connect.Proxy == nil { return nil, nil } // NodeService performs some simple normalization like copying ID from Name // which we shouldn't hard code ourselves here... ns := s.NodeService() execMode, err := NewProxyExecMode(s.Connect.Proxy.ExecMode) if err != nil { return nil, err } p := &ConnectManagedProxy{ ExecMode: execMode, Command: s.Connect.Proxy.Command, Config: s.Connect.Proxy.Config, // ProxyService will be setup when the agent registers the configured // proxies and starts them etc. TargetServiceID: ns.ID, } return p, nil } // Validate validates the service definition. This also calls the underlying // Validate method on the NodeService. // // NOTE(mitchellh): This currently only validates fields related to Connect // and is incomplete with regards to other fields. func (s *ServiceDefinition) Validate() error { var result error if s.Kind == ServiceKindTypical { if s.Connect != nil { if s.Connect.Proxy != nil { if s.Connect.Native { result = multierror.Append(result, fmt.Errorf( "Services that are Connect native may not have a proxy configuration")) } if s.Port == 0 { result = multierror.Append(result, fmt.Errorf( "Services with a Connect managed proxy must have a port set")) } } } } // Validate the NodeService which covers a lot if err := s.NodeService().Validate(); err != nil { result = multierror.Append(result, err) } return result } func (s *ServiceDefinition) CheckTypes() (checks CheckTypes, err error) { if !s.Check.Empty() { err := s.Check.Validate() if err != nil { return nil, err } checks = append(checks, &s.Check) } for _, check := range s.Checks { if err := check.Validate(); err != nil { return nil, err } checks = append(checks, check) } return checks, nil } // ServiceDefinitionConnectProxy is the connect proxy config within a service // registration. Note this is duplicated in config.ServiceConnectProxy and needs // to be kept in sync. type ServiceDefinitionConnectProxy struct { Command []string `json:",omitempty"` ExecMode string `json:",omitempty"` Config map[string]interface{} `json:",omitempty"` } func (p *ServiceDefinitionConnectProxy) MarshalJSON() ([]byte, error) { type typeCopy ServiceDefinitionConnectProxy copy := typeCopy(*p) // If we have config, then we want to run it through our proxyConfigWalker // which is a reflectwalk implementation that attempts to turn arbitrary // interface{} values into JSON-safe equivalents (more or less). This // should always work because the config input is either HCL or JSON and // both are JSON compatible. if copy.Config != nil { configCopyRaw, err := copystructure.Copy(copy.Config) if err != nil { return nil, err } configCopy, ok := configCopyRaw.(map[string]interface{}) if !ok { // This should never fail because we KNOW the input type, // but we don't ever want to risk the panic. return nil, fmt.Errorf("internal error: config copy is not right type") } if err := reflectwalk.Walk(configCopy, &proxyConfigWalker{}); err != nil { return nil, err } copy.Config = configCopy } return json.Marshal(©) } var typMapIfaceIface = reflect.TypeOf(map[interface{}]interface{}{}) // proxyConfigWalker implements interfaces for the reflectwalk package // (github.com/mitchellh/reflectwalk) that can be used to automatically // make the proxy configuration safe for JSON usage. // // Most of the implementation here is just keeping track of where we are // in the reflectwalk process, so that we can replace values. The key logic // is in Slice() and SliceElem(). // // In particular we're looking to replace two cases the msgpack codec causes: // // 1.) String values get turned into byte slices. JSON will base64-encode // this and we don't want that, so we convert them back to strings. // // 2.) Nested maps turn into map[interface{}]interface{}. JSON cannot // encode this, so we need to turn it back into map[string]interface{}. // // This is tested via the TestServiceDefinitionConnectProxy_json test. type proxyConfigWalker struct { lastValue reflect.Value // lastValue of map, required for replacement loc, lastLoc reflectwalk.Location // locations cs []reflect.Value // container stack csKey []reflect.Value // container keys (maps) stack csData interface{} // current container data sliceIndex []int // slice index stack (one for each slice in cs) } func (w *proxyConfigWalker) Enter(loc reflectwalk.Location) error { w.lastLoc = w.loc w.loc = loc return nil } func (w *proxyConfigWalker) Exit(loc reflectwalk.Location) error { w.loc = reflectwalk.None w.lastLoc = reflectwalk.None switch loc { case reflectwalk.Map: w.cs = w.cs[:len(w.cs)-1] case reflectwalk.MapValue: w.csKey = w.csKey[:len(w.csKey)-1] case reflectwalk.Slice: // Split any values that need to be split w.cs = w.cs[:len(w.cs)-1] case reflectwalk.SliceElem: w.csKey = w.csKey[:len(w.csKey)-1] w.sliceIndex = w.sliceIndex[:len(w.sliceIndex)-1] } return nil } func (w *proxyConfigWalker) Map(m reflect.Value) error { w.cs = append(w.cs, m) return nil } func (w *proxyConfigWalker) MapElem(m, k, v reflect.Value) error { w.csData = k w.csKey = append(w.csKey, k) w.lastValue = v return nil } func (w *proxyConfigWalker) Slice(v reflect.Value) error { // If we find a []byte slice, it is an HCL-string converted to []byte. // Convert it back to a Go string and replace the value so that JSON // doesn't base64-encode it. if v.Type() == reflect.TypeOf([]byte{}) { resultVal := reflect.ValueOf(string(v.Interface().([]byte))) switch w.lastLoc { case reflectwalk.MapKey: m := w.cs[len(w.cs)-1] // Delete the old value var zero reflect.Value m.SetMapIndex(w.csData.(reflect.Value), zero) // Set the new key with the existing value m.SetMapIndex(resultVal, w.lastValue) // Set the key to be the new key w.csData = resultVal case reflectwalk.MapValue: // If we're in a map, then the only way to set a map value is // to set it directly. m := w.cs[len(w.cs)-1] mk := w.csData.(reflect.Value) m.SetMapIndex(mk, resultVal) case reflectwalk.Slice: s := w.cs[len(w.cs)-1] s.Index(w.sliceIndex[len(w.sliceIndex)-1]).Set(resultVal) default: return fmt.Errorf("cannot convert []byte") } } w.cs = append(w.cs, v) return nil } func (w *proxyConfigWalker) SliceElem(i int, elem reflect.Value) error { w.csKey = append(w.csKey, reflect.ValueOf(i)) w.sliceIndex = append(w.sliceIndex, i) // We're looking specifically for map[interface{}]interface{}, but the // values in a slice are wrapped up in interface{} so we need to unwrap // that first. Therefore, we do three checks: 1.) is it valid? so we // don't panic, 2.) is it an interface{}? so we can unwrap it and 3.) // after unwrapping the interface do we have the map we expect? if !elem.IsValid() { return nil } if elem.Kind() != reflect.Interface { return nil } if inner := elem.Elem(); inner.Type() == typMapIfaceIface { // map[interface{}]interface{}, attempt to weakly decode into string keys var target map[string]interface{} if err := mapstructure.WeakDecode(inner.Interface(), &target); err != nil { return err } elem.Set(reflect.ValueOf(target)) } return nil }