Initial QSfera import

Server/vendor/go-micro.dev/v4/api/handler/rpc/rpc.go

@@ -0,0 +1,564 @@
+// Package rpc is a go-micro rpc handler.
+package rpc
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/textproto"
+	"strconv"
+	"strings"
+
+	jsonpatch "github.com/evanphx/json-patch/v5"
+	"github.com/oxtoacart/bpool"
+	"go-micro.dev/v4/api/handler"
+	"go-micro.dev/v4/api/internal/proto"
+	"go-micro.dev/v4/api/router"
+	"go-micro.dev/v4/client"
+	"go-micro.dev/v4/codec"
+	"go-micro.dev/v4/codec/jsonrpc"
+	"go-micro.dev/v4/codec/protorpc"
+	"go-micro.dev/v4/errors"
+	log "go-micro.dev/v4/logger"
+	"go-micro.dev/v4/metadata"
+	"go-micro.dev/v4/registry"
+	"go-micro.dev/v4/selector"
+	"go-micro.dev/v4/util/ctx"
+	"go-micro.dev/v4/util/qson"
+)
+
+const (
+	// Handler is the name of this handler.
+	Handler   = "rpc"
+	packageID = "go.micro.api"
+)
+
+var (
+	// supported json codecs.
+	jsonCodecs = []string{
+		"application/grpc+json",
+		"application/json",
+		"application/json-rpc",
+	}
+
+	// support proto codecs.
+	protoCodecs = []string{
+		"application/grpc",
+		"application/grpc+proto",
+		"application/proto",
+		"application/protobuf",
+		"application/proto-rpc",
+		"application/octet-stream",
+	}
+
+	bufferPool = bpool.NewSizedBufferPool(1024, 8)
+)
+
+type rpcHandler struct {
+	opts handler.Options
+}
+
+type buffer struct {
+	io.ReadCloser
+}
+
+func (b *buffer) Write(_ []byte) (int, error) {
+	return 0, nil
+}
+
+// strategy is a hack for selection.
+func strategy(services []*registry.Service) selector.Strategy {
+	return func(_ []*registry.Service) selector.Next {
+		// ignore input to this function, use services above
+		return selector.Random(services)
+	}
+}
+
+func (h *rpcHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	logger := h.opts.Logger
+	bsize := handler.DefaultMaxRecvSize
+
+	if h.opts.MaxRecvSize > 0 {
+		bsize = h.opts.MaxRecvSize
+	}
+
+	r.Body = http.MaxBytesReader(w, r.Body, bsize)
+
+	defer r.Body.Close()
+
+	var service *router.Route
+
+	if h.opts.Router != nil {
+		// try get service from router
+		s, err := h.opts.Router.Route(r)
+		if err != nil {
+			werr := writeError(w, r, errors.InternalServerError(packageID, err.Error()))
+			if werr != nil {
+				logger.Log(log.ErrorLevel, werr)
+			}
+
+			return
+		}
+
+		service = s
+	} else {
+		// we have no way of routing the request
+		werr := writeError(w, r, errors.InternalServerError(packageID, "no route found"))
+		if werr != nil {
+			logger.Log(log.ErrorLevel, werr)
+		}
+		return
+	}
+
+	contentType := r.Header.Get("Content-Type")
+
+	// Strip charset from Content-Type (like `application/json; charset=UTF-8`)
+	if idx := strings.IndexRune(contentType, ';'); idx >= 0 {
+		contentType = contentType[:idx]
+	}
+
+	// micro client
+	myClient := h.opts.Client
+
+	// create context
+	myContext := ctx.FromRequest(r)
+	// get context from http handler wrappers
+	md, ok := metadata.FromContext(r.Context())
+	if !ok {
+		md = make(metadata.Metadata)
+	}
+	// fill contex with http headers
+	md["Host"] = r.Host
+	md["Method"] = r.Method
+	// get canonical headers
+	for k := range r.Header {
+		// may be need to get all values for key like r.Header.Values() provide in go 1.14
+		md[textproto.CanonicalMIMEHeaderKey(k)] = r.Header.Get(k)
+	}
+
+	// merge context with overwrite
+	myContext = metadata.MergeContext(myContext, md, true)
+
+	// set merged context to request
+	*r = *r.Clone(myContext)
+	// if stream we currently only support json
+	if isStream(r, service) {
+		// drop older context as it can have timeouts and create new
+		//		md, _ := metadata.FromContext(cx)
+		// serveWebsocket(context.TODO(), w, r, service, c)
+		if err := serveWebsocket(myContext, w, r, service, myClient); err != nil {
+			logger.Log(log.ErrorLevel, err)
+		}
+
+		return
+	}
+
+	// create strategy
+	mySelector := selector.WithStrategy(strategy(service.Versions))
+
+	// walk the standard call path
+	// get payload
+	br, err := requestPayload(r)
+	if err != nil {
+		if werr := writeError(w, r, err); werr != nil {
+			logger.Log(log.ErrorLevel, werr)
+		}
+
+		return
+	}
+
+	var rsp []byte
+
+	switch {
+	// proto codecs
+	case hasCodec(contentType, protoCodecs):
+		request := &proto.Message{}
+		// if the extracted payload isn't empty lets use it
+		if len(br) > 0 {
+			request = proto.NewMessage(br)
+		}
+
+		// create request/response
+		response := &proto.Message{}
+
+		req := myClient.NewRequest(
+			service.Service,
+			service.Endpoint.Name,
+			request,
+			client.WithContentType(contentType),
+		)
+
+		// make the call
+		if err := myClient.Call(myContext, req, response, client.WithSelectOption(mySelector)); err != nil {
+			if werr := writeError(w, r, err); werr != nil {
+				logger.Log(log.ErrorLevel, werr)
+			}
+
+			return
+		}
+
+		// marshall response
+		rsp, err = response.Marshal()
+		if err != nil {
+			if werr := writeError(w, r, err); werr != nil {
+				logger.Log(log.ErrorLevel, werr)
+			}
+
+			return
+		}
+
+	default:
+		// if json codec is not present set to json
+		if !hasCodec(contentType, jsonCodecs) {
+			contentType = "application/json"
+		}
+
+		// default to trying json
+		var request json.RawMessage
+		// if the extracted payload isn't empty lets use it
+		if len(br) > 0 {
+			request = json.RawMessage(br)
+		}
+
+		// create request/response
+		var response json.RawMessage
+
+		req := myClient.NewRequest(
+			service.Service,
+			service.Endpoint.Name,
+			&request,
+			client.WithContentType(contentType),
+		)
+		// make the call
+		if err := myClient.Call(myContext, req, &response, client.WithSelectOption(mySelector)); err != nil {
+			if werr := writeError(w, r, err); werr != nil {
+				logger.Log(log.ErrorLevel, werr)
+			}
+
+			return
+		}
+
+		// marshall response
+		rsp, err = response.MarshalJSON()
+		if err != nil {
+			if werr := writeError(w, r, err); werr != nil {
+				logger.Log(log.ErrorLevel, werr)
+			}
+
+			return
+		}
+	}
+
+	// write the response
+	if err := writeResponse(w, r, rsp); err != nil {
+		logger.Log(log.ErrorLevel, err)
+	}
+}
+
+func (h *rpcHandler) String() string {
+	return Handler
+}
+
+func hasCodec(ct string, codecs []string) bool {
+	for _, codec := range codecs {
+		if ct == codec {
+			return true
+		}
+	}
+
+	return false
+}
+
+// requestPayload takes a *http.Request.
+// If the request is a GET the query string parameters are extracted and marshaled to JSON and the raw bytes are returned.
+// If the request method is a POST the request body is read and returned.
+func requestPayload(r *http.Request) ([]byte, error) {
+	var err error
+
+	// we have to decode json-rpc and proto-rpc because we suck
+	// well actually because there's no proxy codec right now
+
+	myCt := r.Header.Get("Content-Type")
+
+	switch {
+	case strings.Contains(myCt, "application/json-rpc"):
+		msg := codec.Message{
+			Type:   codec.Request,
+			Header: make(map[string]string),
+		}
+
+		c := jsonrpc.NewCodec(&buffer{r.Body})
+		if err = c.ReadHeader(&msg, codec.Request); err != nil {
+			return nil, err
+		}
+
+		var raw json.RawMessage
+		if err = c.ReadBody(&raw); err != nil {
+			return nil, err
+		}
+
+		return ([]byte)(raw), nil
+	case strings.Contains(myCt, "application/proto-rpc"), strings.Contains(myCt, "application/octet-stream"):
+		msg := codec.Message{
+			Type:   codec.Request,
+			Header: make(map[string]string),
+		}
+
+		c := protorpc.NewCodec(&buffer{r.Body})
+		if err = c.ReadHeader(&msg, codec.Request); err != nil {
+			return nil, err
+		}
+
+		var raw proto.Message
+		if err = c.ReadBody(&raw); err != nil {
+			return nil, err
+		}
+
+		return raw.Marshal()
+	case strings.Contains(myCt, "application/www-x-form-urlencoded"), strings.Contains(myCt, "application/x-www-form-urlencoded"):
+		if err := r.ParseForm(); err != nil {
+			return nil, err
+		}
+
+		// generate a new set of values from the form
+		vals := make(map[string]string)
+		for k, v := range r.Form {
+			vals[k] = strings.Join(v, ",")
+		}
+
+		// marshal
+		return json.Marshal(vals)
+		// TODO: application/grpc
+	}
+
+	// otherwise as per usual
+	ctx := r.Context()
+
+	// dont user meadata.FromContext as it mangles names
+	md, ok := metadata.FromContext(ctx)
+	if !ok {
+		md = make(map[string]string)
+	}
+
+	// allocate maximum
+	matches := make(map[string]interface{}, len(md))
+	bodydst := ""
+
+	// get fields from url path
+	for k, v := range md {
+		k = strings.ToLower(k)
+		// filter own keys
+		if strings.HasPrefix(k, "x-api-field-") {
+			matches[strings.TrimPrefix(k, "x-api-field-")] = v
+
+			delete(md, k)
+		} else if k == "x-api-body" {
+			bodydst = v
+
+			delete(md, k)
+		}
+	}
+
+	// map of all fields
+	req := make(map[string]interface{}, len(md))
+
+	// get fields from url values
+	if len(r.URL.RawQuery) > 0 {
+		umd := make(map[string]interface{})
+
+		err = qson.Unmarshal(&umd, r.URL.RawQuery)
+		if err != nil {
+			return nil, err
+		}
+
+		for k, v := range umd {
+			matches[k] = v
+		}
+	}
+
+	// restore context without fields
+	*r = *r.Clone(metadata.NewContext(ctx, md))
+
+	for k, v := range matches {
+		ps := strings.Split(k, ".")
+		if len(ps) == 1 {
+			req[k] = v
+			continue
+		}
+
+		em := make(map[string]interface{})
+		em[ps[len(ps)-1]] = v
+
+		for i := len(ps) - 2; i > 0; i-- {
+			nm := make(map[string]interface{})
+			nm[ps[i]] = em
+			em = nm
+		}
+
+		if vm, ok := req[ps[0]]; ok {
+			// nested map
+			nm := vm.(map[string]interface{})
+			for vk, vv := range em {
+				nm[vk] = vv
+			}
+
+			req[ps[0]] = nm
+		} else {
+			req[ps[0]] = em
+		}
+	}
+
+	pathbuf := []byte("{}")
+	if len(req) > 0 {
+		pathbuf, err = json.Marshal(req)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	urlbuf := []byte("{}")
+
+	out, err := jsonpatch.MergeMergePatches(urlbuf, pathbuf)
+	if err != nil {
+		return nil, err
+	}
+
+	switch r.Method {
+	case http.MethodGet:
+		// empty response
+		if strings.Contains(myCt, "application/json") && string(out) == "{}" {
+			return out, nil
+		} else if string(out) == "{}" && !strings.Contains(myCt, "application/json") {
+			return []byte{}, nil
+		}
+
+		return out, nil
+	case http.MethodPatch, http.MethodPost, http.MethodPut, http.MethodDelete:
+		bodybuf := []byte("{}")
+		buf := bufferPool.Get()
+
+		defer bufferPool.Put(buf)
+		if _, err := buf.ReadFrom(r.Body); err != nil {
+			return nil, err
+		}
+
+		if b := buf.Bytes(); len(b) > 0 {
+			bodybuf = b
+		}
+
+		if bodydst == "" || bodydst == "*" {
+			if out, err = jsonpatch.MergeMergePatches(out, bodybuf); err == nil {
+				return out, nil
+			}
+		}
+
+		var jsonbody map[string]interface{}
+		if json.Valid(bodybuf) {
+			if err = json.Unmarshal(bodybuf, &jsonbody); err != nil {
+				return nil, err
+			}
+		}
+
+		dstmap := make(map[string]interface{})
+		ps := strings.Split(bodydst, ".")
+		if len(ps) == 1 {
+			if jsonbody != nil {
+				dstmap[ps[0]] = jsonbody
+			} else {
+				// old unexpected behavior
+				dstmap[ps[0]] = bodybuf
+			}
+		} else {
+			em := make(map[string]interface{})
+			if jsonbody != nil {
+				em[ps[len(ps)-1]] = jsonbody
+			} else {
+				// old unexpected behavior
+				em[ps[len(ps)-1]] = bodybuf
+			}
+			for i := len(ps) - 2; i > 0; i-- {
+				nm := make(map[string]interface{})
+				nm[ps[i]] = em
+				em = nm
+			}
+			dstmap[ps[0]] = em
+		}
+
+		bodyout, err := json.Marshal(dstmap)
+		if err != nil {
+			return nil, err
+		}
+
+		if out, err = jsonpatch.MergeMergePatches(out, bodyout); err == nil {
+			return out, nil
+		}
+
+		return bodybuf, nil
+	}
+
+	return []byte{}, nil
+}
+
+func writeError(rsp http.ResponseWriter, req *http.Request, err error) error {
+	ce := errors.Parse(err.Error())
+
+	switch ce.Code {
+	case 0:
+		// assuming it's totally screwed
+		ce.Code = http.StatusInternalServerError
+		ce.Id = packageID
+		ce.Status = http.StatusText(http.StatusInternalServerError)
+		ce.Detail = "error during request: " + ce.Detail
+
+		rsp.WriteHeader(http.StatusInternalServerError)
+	default:
+		rsp.WriteHeader(int(ce.Code))
+	}
+
+	// response content type
+	rsp.Header().Set("Content-Type", "application/json")
+
+	// Set trailers
+	if strings.Contains(req.Header.Get("Content-Type"), "application/grpc") {
+		rsp.Header().Set("Trailer", "grpc-status")
+		rsp.Header().Set("Trailer", "grpc-message")
+		rsp.Header().Set("grpc-status", "13")
+		rsp.Header().Set("grpc-message", ce.Detail)
+	}
+
+	_, werr := rsp.Write([]byte(ce.Error()))
+
+	return werr
+}
+
+func writeResponse(w http.ResponseWriter, r *http.Request, rsp []byte) error {
+	w.Header().Set("Content-Type", r.Header.Get("Content-Type"))
+	w.Header().Set("Content-Length", strconv.Itoa(len(rsp)))
+
+	// Set trailers
+	if strings.Contains(r.Header.Get("Content-Type"), "application/grpc") {
+		w.Header().Set("Trailer", "grpc-status")
+		w.Header().Set("Trailer", "grpc-message")
+		w.Header().Set("grpc-status", "0")
+		w.Header().Set("grpc-message", "")
+	}
+
+	// write 204 status if rsp is nil
+	if len(rsp) == 0 {
+		w.WriteHeader(http.StatusNoContent)
+	}
+
+	// write response
+	_, err := w.Write(rsp)
+
+	return err
+}
+
+// NewHandler returns a new RPC handler.
+func NewHandler(opts ...handler.Option) handler.Handler {
+	options := handler.NewOptions(opts...)
+
+	return &rpcHandler{
+		opts: options,
+	}
+}