github.com/kaydxh/golang@v0.0.131/go/net/http/ip.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 http
    23  
    24  import (
    25  	"fmt"
    26  	"net"
    27  	"net/http"
    28  	"strings"
    29  )
    30  
    31  // returns IP address from request.
    32  // It will lookup IP in  X-Forwarded-For and X-Real-IP headers.
    33  func GetIPFromRequest(r *http.Request) (net.IP, error) {
    34  	if r == nil {
    35  		return nil, fmt.Errorf("http request is nil")
    36  	}
    37  
    38  	ip := r.Header.Get("X-Forwarded-For")
    39  	if ip != "" {
    40  		parts := strings.SplitN(ip, ",", 2)
    41  		part := strings.TrimSpace(parts[0])
    42  		return net.ParseIP(part), nil
    43  	}
    44  
    45  	ip = strings.TrimSpace(r.Header.Get("X-Real-IP"))
    46  	if ip != "" {
    47  		return net.ParseIP(ip), nil
    48  	}
    49  
    50  	remoteAddr := strings.TrimSpace(r.RemoteAddr)
    51  	host, _, err := net.SplitHostPort(remoteAddr)
    52  	if err != nil {
    53  		return net.ParseIP(remoteAddr), err
    54  	}
    55  
    56  	return net.ParseIP(host), nil
    57  }