Merge pull request #88 from filecoin-project/feat/reverese-calling

Features for reverse calls, notifs, custom-params

.circleci/config.yml

@@ -4,7 +4,7 @@ orbs:
 executors:
   golang:
     docker:
-      - image: circleci/golang:1.13
+      - image: cimg/go:1.18.8
     resource_class: medium
 jobs:
   test:
@@ -31,7 +31,7 @@ jobs:
       - go/mod-download
       - go/install-golangci-lint:
           gobin: $HOME/.local/bin
-          version: 1.23.8
+          version: 1.50.1
       - run:
           command: $HOME/.local/bin/golangci-lint run -v --concurrency 2
 workflows:

client.go

@@ -167,16 +167,18 @@ func httpClient(ctx context.Context, addr string, namespace string, outs []inter
 		defer httpResp.Body.Close()
 
 		var resp clientResponse
-		if err := json.NewDecoder(httpResp.Body).Decode(&resp); err != nil {
-			return clientResponse{}, xerrors.Errorf("http status %s unmarshaling response: %w", httpResp.Status, err)
-		}
+		if cr.req.ID != nil { // non-notification
+			if err := json.NewDecoder(httpResp.Body).Decode(&resp); err != nil {
+				return clientResponse{}, xerrors.Errorf("http status %s unmarshaling response: %w", httpResp.Status, err)
+			}
 
-		if resp.ID, err = normalizeID(resp.ID); err != nil {
-			return clientResponse{}, xerrors.Errorf("failed to response ID: %w", err)
-		}
+			if resp.ID, err = normalizeID(resp.ID); err != nil {
+				return clientResponse{}, xerrors.Errorf("failed to response ID: %w", err)
+			}
 
-		if resp.ID != cr.req.ID {
-			return clientResponse{}, xerrors.New("request and response id didn't match")
+			if resp.ID != cr.req.ID {
+				return clientResponse{}, xerrors.New("request and response id didn't match")
+			}
 		}
 
 		return resp, nil
@@ -220,6 +222,45 @@ func websocketClient(ctx context.Context, addr string, namespace string, outs []
 		errors:        config.errors,
 	}
 
+	requests := c.setupRequestChan()
+
+	stop := make(chan struct{})
+	exiting := make(chan struct{})
+	c.exiting = exiting
+
+	var hnd reqestHandler
+	if len(config.reverseHandlers) > 0 {
+		h := makeHandler(defaultServerConfig())
+		h.aliasedMethods = config.aliasedHandlerMethods
+		for _, reverseHandler := range config.reverseHandlers {
+			h.register(reverseHandler.ns, reverseHandler.hnd)
+		}
+		hnd = h
+	}
+
+	go (&wsConn{
+		conn:             conn,
+		connFactory:      connFactory,
+		reconnectBackoff: config.reconnectBackoff,
+		pingInterval:     config.pingInterval,
+		timeout:          config.timeout,
+		handler:          hnd,
+		requests:         requests,
+		stop:             stop,
+		exiting:          exiting,
+	}).handleWsConn(ctx)
+
+	if err := c.provide(outs); err != nil {
+		return nil, err
+	}
+
+	return func() {
+		close(stop)
+		<-exiting
+	}, nil
+}
+
+func (c *client) setupRequestChan() chan clientRequest {
 	requests := make(chan clientRequest)
 
 	c.doRequest = func(ctx context.Context, cr clientRequest) (clientResponse, error) {
@@ -245,12 +286,18 @@ func websocketClient(ctx context.Context, addr string, namespace string, outs []
 			case <-ctxDone: // send cancel request
 				ctxDone = nil
 
+				rp, err := json.Marshal([]param{{v: reflect.ValueOf(cr.req.ID)}})
+				if err != nil {
+					return clientResponse{}, xerrors.Errorf("marshalling cancel request: %w", err)
+				}
+
 				cancelReq := clientRequest{
 					req: request{
 						Jsonrpc: "2.0",
 						Method:  wsCancel,
-						Params:  []param{{v: reflect.ValueOf(cr.req.ID)}},
+						Params:  rp,
 					},
+					ready: make(chan clientResponse, 1),
 				}
 				select {
 				case requests <- cancelReq:
@@ -264,30 +311,7 @@ func websocketClient(ctx context.Context, addr string, namespace string, outs []
 		return resp, nil
 	}
 
-	stop := make(chan struct{})
-	exiting := make(chan struct{})
-	c.exiting = exiting
-
-	go (&wsConn{
-		conn:             conn,
-		connFactory:      connFactory,
-		reconnectBackoff: config.reconnectBackoff,
-		pingInterval:     config.pingInterval,
-		timeout:          config.timeout,
-		handler:          nil,
-		requests:         requests,
-		stop:             stop,
-		exiting:          exiting,
-	}).handleWsConn(ctx)
-
-	if err := c.provide(outs); err != nil {
-		return nil, err
-	}
-
-	return func() {
-		close(stop)
-		<-exiting
-	}, nil
+	return requests
 }
 
 func (c *client) provide(outs []interface{}) error {
@@ -433,10 +457,15 @@ type rpcFunc struct {
 	valOut int
 	errOut int
 
-	hasCtx               int
+	// hasCtx is 1 if the function has a context.Context as its first argument.
+	// Used as the number of the first non-context argument.
+	hasCtx int
+
+	hasRawParams         bool
 	returnValueIsChannel bool
 
-	retry bool
+	retry  bool
+	notify bool
 }
 
 func (fn *rpcFunc) processResponse(resp clientResponse, rval reflect.Value) []reflect.Value {
@@ -471,21 +500,47 @@ func (fn *rpcFunc) processError(err error) []reflect.Value {
 }
 
 func (fn *rpcFunc) handleRpcCall(args []reflect.Value) (results []reflect.Value) {
-	var id interface{} = atomic.AddInt64(&fn.client.idCtr, 1)
-	params := make([]param, len(args)-fn.hasCtx)
-	for i, arg := range args[fn.hasCtx:] {
-		enc, found := fn.client.paramEncoders[arg.Type()]
-		if found {
-			// custom param encoder
-			var err error
-			arg, err = enc(arg)
-			if err != nil {
-				return fn.processError(fmt.Errorf("sendRequest failed: %w", err))
-			}
+	var id interface{}
+	if !fn.notify {
+		id = atomic.AddInt64(&fn.client.idCtr, 1)
+
+		// Prepare the ID to send on the wire.
+		// We track int64 ids as float64 in the inflight map (because that's what
+		// they'll be decoded to). encoding/json outputs numbers with their minimal
+		// encoding, avoding the decimal point when possible, i.e. 3 will never get
+		// converted to 3.0.
+		var err error
+		id, err = normalizeID(id)
+		if err != nil {
+			return fn.processError(fmt.Errorf("failed to normalize id")) // should probably panic
 		}
+	}
 
-		params[i] = param{
-			v: arg,
+	var serializedParams json.RawMessage
+
+	if fn.hasRawParams {
+		serializedParams = json.RawMessage(args[fn.hasCtx].Interface().(RawParams))
+	} else {
+		params := make([]param, len(args)-fn.hasCtx)
+		for i, arg := range args[fn.hasCtx:] {
+			enc, found := fn.client.paramEncoders[arg.Type()]
+			if found {
+				// custom param encoder
+				var err error
+				arg, err = enc(arg)
+				if err != nil {
+					return fn.processError(fmt.Errorf("sendRequest failed: %w", err))
+				}
+			}
+
+			params[i] = param{
+				v: arg,
+			}
+		}
+		var err error
+		serializedParams, err = json.Marshal(params)
+		if err != nil {
+			return fn.processError(fmt.Errorf("marshaling params failed: %w", err))
 		}
 	}
 
@@ -506,21 +561,11 @@ func (fn *rpcFunc) handleRpcCall(args []reflect.Value) (results []reflect.Value)
 		retVal, chCtor = fn.client.makeOutChan(ctx, fn.ftyp, fn.valOut)
 	}
 
-	// Prepare the ID to send on the wire.
-	// We track int64 ids as float64 in the inflight map (because that's what
-	// they'll be decoded to). encoding/json outputs numbers with their minimal
-	// encoding, avoding the decimal point when possible, i.e. 3 will never get
-	// converted to 3.0.
-	id, err := normalizeID(id)
-	if err != nil {
-		return fn.processError(fmt.Errorf("failed to normalize id")) // should probably panic
-	}
-
 	req := request{
 		Jsonrpc: "2.0",
 		ID:      id,
-		Method:  fn.client.namespace + "." + fn.name,
-		Params:  params,
+		Method:  fn.name,
+		Params:  serializedParams,
 	}
 
 	if span != nil {
@@ -538,6 +583,7 @@ func (fn *rpcFunc) handleRpcCall(args []reflect.Value) (results []reflect.Value)
 		minDelay: methodMinRetryDelay,
 	}
 
+	var err error
 	var resp clientResponse
 	// keep retrying if got a forced closed websocket conn and calling method
 	// has retry annotation
@@ -547,7 +593,7 @@ func (fn *rpcFunc) handleRpcCall(args []reflect.Value) (results []reflect.Value)
 			return fn.processError(fmt.Errorf("sendRequest failed: %w", err))
 		}
 
-		if resp.ID != req.ID {
+		if !fn.notify && resp.ID != req.ID {
 			return fn.processError(xerrors.New("request and response id didn't match"))
 		}
 
@@ -575,24 +621,48 @@ func (fn *rpcFunc) handleRpcCall(args []reflect.Value) (results []reflect.Value)
 	return fn.processResponse(resp, retVal())
 }
 
+const (
+	ProxyTagRetry     = "retry"
+	ProxyTagNotify    = "notify"
+	ProxyTagRPCMethod = "rpc_method"
+)
+
 func (c *client) makeRpcFunc(f reflect.StructField) (reflect.Value, error) {
 	ftyp := f.Type
 	if ftyp.Kind() != reflect.Func {
 		return reflect.Value{}, xerrors.New("handler field not a func")
 	}
 
+	name := c.namespace + "." + f.Name
+	if tag, ok := f.Tag.Lookup(ProxyTagRPCMethod); ok {
+		name = tag
+	}
+
 	fun := &rpcFunc{
 		client: c,
 		ftyp:   ftyp,
-		name:   f.Name,
-		retry:  f.Tag.Get("retry") == "true",
+		name:   name,
+		retry:  f.Tag.Get(ProxyTagRetry) == "true",
+		notify: f.Tag.Get(ProxyTagNotify) == "true",
 	}
 	fun.valOut, fun.errOut, fun.nout = processFuncOut(ftyp)
 
+	if fun.valOut != -1 && fun.notify {
+		return reflect.Value{}, xerrors.New("notify methods cannot return values")
+	}
+
+	fun.returnValueIsChannel = fun.valOut != -1 && ftyp.Out(fun.valOut).Kind() == reflect.Chan
+
 	if ftyp.NumIn() > 0 && ftyp.In(0) == contextType {
 		fun.hasCtx = 1
 	}
-	fun.returnValueIsChannel = fun.valOut != -1 && ftyp.Out(fun.valOut).Kind() == reflect.Chan
+	// note: hasCtx is also the number of the first non-context argument
+	if ftyp.NumIn() > fun.hasCtx && ftyp.In(fun.hasCtx) == rtRawParams {
+		if ftyp.NumIn() > fun.hasCtx+1 {
+			return reflect.Value{}, xerrors.New("raw params can't be mixed with other arguments")
+		}
+		fun.hasRawParams = true
+	}
 
 	return reflect.MakeFunc(ftyp, fun.handleRpcCall), nil
 }

go.mod

@@ -1,6 +1,6 @@
 module github.com/filecoin-project/go-jsonrpc
 
-go 1.14
+go 1.18
 
 require (
 	github.com/google/uuid v1.1.1
@@ -12,3 +12,12 @@ require (
 	go.uber.org/zap v1.14.1
 	golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543
 )
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/golang/groupcache v0.0.0-20190702054246-869f871628b6 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	go.uber.org/atomic v1.6.0 // indirect
+	go.uber.org/multierr v1.5.0 // indirect
+	gopkg.in/yaml.v2 v2.2.2 // indirect
+)