github.com/kaydxh/golang@v0.0.131/pkg/grpc-gateway/gateway_handler.go (about)

     1  /*
     2   *Copyright (c) 2022, kaydxh
     3   *
     4   *Permission is hereby granted, free of charge, to any person obtaining a copy
     5   *of this software and associated documentation files (the "Software"), to deal
     6   *in the Software without restriction, including without limitation the rights
     7   *to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     8   *copies of the Software, and to permit persons to whom the Software is
     9   *furnished to do so, subject to the following conditions:
    10   *
    11   *The above copyright notice and this permission notice shall be included in all
    12   *copies or substantial portions of the Software.
    13   *
    14   *THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    15   *IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    16   *FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    17   *AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    18   *LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    19   *OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    20   *SOFTWARE.
    21   */
    22  package grpcgateway
    23  
    24  import (
    25  	"context"
    26  	"net/http"
    27  	"strings"
    28  
    29  	"github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
    30  	"golang.org/x/net/http2"
    31  	"golang.org/x/net/http2/h2c"
    32  	"google.golang.org/grpc"
    33  )
    34  
    35  type GRPCHandler interface {
    36  	Register(srv *grpc.Server)
    37  }
    38  
    39  type GRPCHandlerFunc func(srv *grpc.Server)
    40  
    41  func (h GRPCHandlerFunc) Register(srv *grpc.Server) {
    42  	h(srv)
    43  }
    44  
    45  type HTTPHandler interface {
    46  	Register(ctx context.Context, mux *runtime.ServeMux, endpoint string, opts []grpc.DialOption) error
    47  }
    48  
    49  type HTTPHandlerFunc func(ctx context.Context, mux *runtime.ServeMux, endpoint string, opts []grpc.DialOption) error
    50  
    51  // ServeMux is a request multiplexer for grpc-gateway.
    52  // It matches http requests to patterns and invokes the corresponding handler.
    53  
    54  // grpc.DialOption configures how we set up the connection. grpc client->
    55  // grpc server
    56  
    57  func (h HTTPHandlerFunc) Register(
    58  	ctx context.Context,
    59  	mux *runtime.ServeMux,
    60  	endpoint string,
    61  	opts []grpc.DialOption,
    62  ) error {
    63  	return h(ctx, mux, endpoint, opts)
    64  }
    65  
    66  // grpcHandlerFunc returns an http.Handler that delegates to grpcServer on incoming gRPC
    67  // connections or otherHandler otherwise. Copied from cockroachdb.
    68  func grpcHandlerFunc(grpcServer *grpc.Server, otherHandler http.Handler) http.Handler {
    69  	return h2c.NewHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    70  		// TODO(tamird): point to merged gRPC code rather than a PR.
    71  		// This is a partial recreation of gRPC's internal checks https://github.com/grpc/grpc-go/pull/514/files#diff-95e9a25b738459a2d3030e1e6fa2a718R61
    72  		if r.ProtoMajor == 2 && strings.Contains(r.Header.Get("Content-Type"), "application/grpc") {
    73  			grpcServer.ServeHTTP(w, r)
    74  		} else {
    75  			otherHandler.ServeHTTP(w, r)
    76  		}
    77  
    78  	}), &http2.Server{})
    79  }