header_methods.go

   1 //
   2 // Copyright © 2011-2018 Guy M. Allard
   3 //
   4 // Licensed under the Apache License, Version 2.0 (the "License");
   5 // you may not use this file except in compliance with the License.
   6 // You may obtain a copy of the License at
   7 //
   8 //     http://www.apache.org/licenses/LICENSE-2.0
   9 //
  10 // Unless required by applicable law or agreed to in writing, software
  11 // distributed under the License is distributed on an "AS IS" BASIS,
  12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 // See the License for the specific language governing permissions and
  14 // limitations under the License.
  15 //
  16
  17 package stompngo
  18
  19 import (
  20         "unicode/utf8"
  21 )
  22
  23 /*
  24         Add appends a key and value pair as a header to a set of Headers.
  25 */
  26 func (h Headers) Add(k, v string) Headers {
  27         r := append(h, k, v)
  28         return r
  29 }
  30
  31 /*
  32         AddHeaders appends one set of Headers to another.
  33 */
  34 func (h Headers) AddHeaders(o Headers) Headers {
  35         r := append(h, o...)
  36         return r
  37 }
  38
  39 /*
  40         Compare compares one set of Headers with another.
  41 */
  42 func (h Headers) Compare(other Headers) bool {
  43         if len(h) != len(other) {
  44                 return false
  45         }
  46         for i, v := range h {
  47                 if v != other[i] {
  48                         return false
  49                 }
  50         }
  51         return true
  52 }
  53
  54 /*
  55         Contains returns true if a set of Headers contains a key.
  56 */
  57 func (h Headers) Contains(k string) (string, bool) {
  58         for i := 0; i < len(h); i += 2 {
  59                 if h[i] == k {
  60                         return h[i+1], true
  61                 }
  62         }
  63         return "", false
  64 }
  65
  66 /*
  67         ContainsKV returns true if a set of Headers contains a key and value pair.
  68 */
  69 func (h Headers) ContainsKV(k string, v string) bool {
  70         for i := 0; i < len(h); i += 2 {
  71                 if h[i] == k && h[i+1] == v {
  72                         return true
  73                 }
  74         }
  75         return false
  76 }
  77
  78 /*
  79         Value returns a header value for a specified key.  If the key is not present
  80         an empty string is returned.
  81 */
  82 func (h Headers) Value(k string) string {
  83         for i := 0; i < len(h); i += 2 {
  84                 if h[i] == k {
  85                         return h[i+1]
  86                 }
  87         }
  88         return ""
  89 }
  90
  91 /*
  92         Index returns the index of a keader key in Headers.  Return -1 if the
  93         key is not present.
  94 */
  95 func (h Headers) Index(k string) int {
  96         r := -1
  97         for i := 0; i < len(h); i += 2 {
  98                 if h[i] == k {
  99                         r = i
 100                         break
 101                 }
 102         }
 103         return r
 104 }
 105
 106 /*
 107         Validate performs bacic validation of a set of Headers.
 108 */
 109 func (h Headers) Validate() error {
 110         if len(h)%2 != 0 {
 111                 return EHDRLEN
 112         }
 113         return nil
 114 }
 115
 116 /*
 117         ValidateUTF8 validates that header strings are UTF8.
 118 */
 119 func (h Headers) ValidateUTF8() (string, error) {
 120         for i := range h {
 121                 if !utf8.ValidString(h[i]) {
 122                         return h[i], EHDRUTF8
 123                 }
 124         }
 125         return "", nil
 126 }
 127
 128 /*
 129         Clone copies a set of Headers.
 130 */
 131 func (h Headers) Clone() Headers {
 132         r := make(Headers, len(h))
 133         copy(r, h)
 134         return r
 135 }
 136
 137 /*
 138         Delete removes a key and value pair from a set of Headers.
 139 */
 140 func (h Headers) Delete(k string) Headers {
 141         r := h.Clone()
 142         i := r.Index(k)
 143         if i >= 0 {
 144                 r = append(r[:i], r[i+2:]...)
 145         }
 146         return r
 147 }
 148
 149 /*
 150         Size returns the size of Headers on the wire, in bytes.
 151 */
 152 func (h Headers) Size(e bool) int64 {
 153         l := 0
 154         for i := 0; i < len(h); i += 2 {
 155                 if e {
 156                         l += len(encode(h[i])) + 1 + len(encode(h[i+1])) + 1
 157                 } else {
 158                         l += len(h[i]) + 1 + len(h[i+1]) + 1
 159                 }
 160         }
 161         return int64(l)
 162 }
 163
 164 /*
 165         String makes Headers a Stringer.
 166 */
 167 func (h Headers) String() string {
 168         ec := h.Validate()
 169         if ec != nil {
 170                 return ec.Error()
 171         }
 172         b := make([]byte, 0, 1024)
 173         for i := 0; i < len(h); i += 2 {
 174                 b = append(b, h[i]+":"+h[i+1]+"\n"...)
 175         }
 176         return string(b)
 177 }
 178
 179 /*
 180         Bytes returns a byte slice of the headers
 181 */
 182 func (h Headers) Bytes() []byte {
 183         b := make([]byte, 0, 1024)
 184         for i := 0; i < len(h); i += 2 {
 185                 b = append(b, h[i]+":"+h[i+1]+"\n"...)
 186         }
 187         return b
 188 }