peridot/vendor/google.golang.org/grpc/internal/grpcutil/method.go
2022-07-07 22:13:21 +02:00

84 lines
2.7 KiB
Go

/*
*
* Copyright 2018 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package grpcutil
import (
"errors"
"strings"
)
// ParseMethod splits service and method from the input. It expects format
// "/service/method".
//
func ParseMethod(methodName string) (service, method string, _ error) {
if !strings.HasPrefix(methodName, "/") {
return "", "", errors.New("invalid method name: should start with /")
}
methodName = methodName[1:]
pos := strings.LastIndex(methodName, "/")
if pos < 0 {
return "", "", errors.New("invalid method name: suffix /method is missing")
}
return methodName[:pos], methodName[pos+1:], nil
}
const baseContentType = "application/grpc"
// ContentSubtype returns the content-subtype for the given content-type. The
// given content-type must be a valid content-type that starts with
// "application/grpc". A content-subtype will follow "application/grpc" after a
// "+" or ";". See
// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests for
// more details.
//
// If contentType is not a valid content-type for gRPC, the boolean
// will be false, otherwise true. If content-type == "application/grpc",
// "application/grpc+", or "application/grpc;", the boolean will be true,
// but no content-subtype will be returned.
//
// contentType is assumed to be lowercase already.
func ContentSubtype(contentType string) (string, bool) {
if contentType == baseContentType {
return "", true
}
if !strings.HasPrefix(contentType, baseContentType) {
return "", false
}
// guaranteed since != baseContentType and has baseContentType prefix
switch contentType[len(baseContentType)] {
case '+', ';':
// this will return true for "application/grpc+" or "application/grpc;"
// which the previous validContentType function tested to be valid, so we
// just say that no content-subtype is specified in this case
return contentType[len(baseContentType)+1:], true
default:
return "", false
}
}
// ContentType builds full content type with the given sub-type.
//
// contentSubtype is assumed to be lowercase
func ContentType(contentSubtype string) string {
if contentSubtype == "" {
return baseContentType
}
return baseContentType + "+" + contentSubtype
}