github.com/polarismesh/polaris@v1.17.8/common/utils/context.go (about)

     1  /**
     2   * Tencent is pleased to support the open source community by making Polaris available.
     3   *
     4   * Copyright (C) 2019 THL A29 Limited, a Tencent company. All rights reserved.
     5   *
     6   * Licensed under the BSD 3-Clause License (the "License");
     7   * you may not use this file except in compliance with the License.
     8   * You may obtain a copy of the License at
     9   *
    10   * https://opensource.org/licenses/BSD-3-Clause
    11   *
    12   * Unless required by applicable law or agreed to in writing, software distributed
    13   * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
    14   * CONDITIONS OF ANY KIND, either express or implied. See the License for the
    15   * specific language governing permissions and limitations under the License.
    16   */
    17  
    18  package utils
    19  
    20  import "context"
    21  
    22  // StringContext is a context key that carries a string.
    23  type StringContext string
    24  
    25  // localhostCtx is a context key that carries localhost info.
    26  type localhostCtx struct{}
    27  
    28  // WithLocalhost 存储localhost
    29  func WithLocalhost(ctx context.Context, localhost string) context.Context {
    30  	return context.WithValue(ctx, localhostCtx{}, localhost)
    31  }
    32  
    33  // ValueLocalhost 获取localhost
    34  func ValueLocalhost(ctx context.Context) string {
    35  	if ctx == nil {
    36  		return ""
    37  	}
    38  
    39  	value, ok := ctx.Value(localhostCtx{}).(string)
    40  	if !ok {
    41  		return ""
    42  	}
    43  
    44  	return value
    45  }