serkant.uluderya | e5afeff | 2021-02-23 18:00:23 +0300 | [diff] [blame] | 1 | package proto |
| 2 | |
| 3 | import ( |
| 4 | "bufio" |
| 5 | "fmt" |
| 6 | "io" |
| 7 | |
| 8 | "github.com/go-redis/redis/v8/internal/util" |
| 9 | ) |
| 10 | |
| 11 | const ( |
| 12 | ErrorReply = '-' |
| 13 | StatusReply = '+' |
| 14 | IntReply = ':' |
| 15 | StringReply = '$' |
| 16 | ArrayReply = '*' |
| 17 | ) |
| 18 | |
| 19 | //------------------------------------------------------------------------------ |
| 20 | |
| 21 | const Nil = RedisError("redis: nil") |
| 22 | |
| 23 | type RedisError string |
| 24 | |
| 25 | func (e RedisError) Error() string { return string(e) } |
| 26 | |
| 27 | func (RedisError) RedisError() {} |
| 28 | |
| 29 | //------------------------------------------------------------------------------ |
| 30 | |
| 31 | type MultiBulkParse func(*Reader, int64) (interface{}, error) |
| 32 | |
| 33 | type Reader struct { |
| 34 | rd *bufio.Reader |
| 35 | _buf []byte |
| 36 | } |
| 37 | |
| 38 | func NewReader(rd io.Reader) *Reader { |
| 39 | return &Reader{ |
| 40 | rd: bufio.NewReader(rd), |
| 41 | _buf: make([]byte, 64), |
| 42 | } |
| 43 | } |
| 44 | |
| 45 | func (r *Reader) Buffered() int { |
| 46 | return r.rd.Buffered() |
| 47 | } |
| 48 | |
| 49 | func (r *Reader) Peek(n int) ([]byte, error) { |
| 50 | return r.rd.Peek(n) |
| 51 | } |
| 52 | |
| 53 | func (r *Reader) Reset(rd io.Reader) { |
| 54 | r.rd.Reset(rd) |
| 55 | } |
| 56 | |
| 57 | func (r *Reader) ReadLine() ([]byte, error) { |
| 58 | line, err := r.readLine() |
| 59 | if err != nil { |
| 60 | return nil, err |
| 61 | } |
| 62 | if isNilReply(line) { |
| 63 | return nil, Nil |
| 64 | } |
| 65 | return line, nil |
| 66 | } |
| 67 | |
| 68 | // readLine that returns an error if: |
| 69 | // - there is a pending read error; |
| 70 | // - or line does not end with \r\n. |
| 71 | func (r *Reader) readLine() ([]byte, error) { |
| 72 | b, err := r.rd.ReadSlice('\n') |
| 73 | if err != nil { |
| 74 | if err != bufio.ErrBufferFull { |
| 75 | return nil, err |
| 76 | } |
| 77 | |
| 78 | full := make([]byte, len(b)) |
| 79 | copy(full, b) |
| 80 | |
| 81 | b, err = r.rd.ReadBytes('\n') |
| 82 | if err != nil { |
| 83 | return nil, err |
| 84 | } |
| 85 | |
| 86 | full = append(full, b...) |
| 87 | b = full |
| 88 | } |
| 89 | if len(b) <= 2 || b[len(b)-1] != '\n' || b[len(b)-2] != '\r' { |
| 90 | return nil, fmt.Errorf("redis: invalid reply: %q", b) |
| 91 | } |
| 92 | return b[:len(b)-2], nil |
| 93 | } |
| 94 | |
| 95 | func (r *Reader) ReadReply(m MultiBulkParse) (interface{}, error) { |
| 96 | line, err := r.ReadLine() |
| 97 | if err != nil { |
| 98 | return nil, err |
| 99 | } |
| 100 | |
| 101 | switch line[0] { |
| 102 | case ErrorReply: |
| 103 | return nil, ParseErrorReply(line) |
| 104 | case StatusReply: |
| 105 | return string(line[1:]), nil |
| 106 | case IntReply: |
| 107 | return util.ParseInt(line[1:], 10, 64) |
| 108 | case StringReply: |
| 109 | return r.readStringReply(line) |
| 110 | case ArrayReply: |
| 111 | n, err := parseArrayLen(line) |
| 112 | if err != nil { |
| 113 | return nil, err |
| 114 | } |
| 115 | if m == nil { |
| 116 | err := fmt.Errorf("redis: got %.100q, but multi bulk parser is nil", line) |
| 117 | return nil, err |
| 118 | } |
| 119 | return m(r, n) |
| 120 | } |
| 121 | return nil, fmt.Errorf("redis: can't parse %.100q", line) |
| 122 | } |
| 123 | |
| 124 | func (r *Reader) ReadIntReply() (int64, error) { |
| 125 | line, err := r.ReadLine() |
| 126 | if err != nil { |
| 127 | return 0, err |
| 128 | } |
| 129 | switch line[0] { |
| 130 | case ErrorReply: |
| 131 | return 0, ParseErrorReply(line) |
| 132 | case IntReply: |
| 133 | return util.ParseInt(line[1:], 10, 64) |
| 134 | default: |
| 135 | return 0, fmt.Errorf("redis: can't parse int reply: %.100q", line) |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | func (r *Reader) ReadString() (string, error) { |
| 140 | line, err := r.ReadLine() |
| 141 | if err != nil { |
| 142 | return "", err |
| 143 | } |
| 144 | switch line[0] { |
| 145 | case ErrorReply: |
| 146 | return "", ParseErrorReply(line) |
| 147 | case StringReply: |
| 148 | return r.readStringReply(line) |
| 149 | case StatusReply: |
| 150 | return string(line[1:]), nil |
| 151 | case IntReply: |
| 152 | return string(line[1:]), nil |
| 153 | default: |
| 154 | return "", fmt.Errorf("redis: can't parse reply=%.100q reading string", line) |
| 155 | } |
| 156 | } |
| 157 | |
| 158 | func (r *Reader) readStringReply(line []byte) (string, error) { |
| 159 | if isNilReply(line) { |
| 160 | return "", Nil |
| 161 | } |
| 162 | |
| 163 | replyLen, err := util.Atoi(line[1:]) |
| 164 | if err != nil { |
| 165 | return "", err |
| 166 | } |
| 167 | |
| 168 | b := make([]byte, replyLen+2) |
| 169 | _, err = io.ReadFull(r.rd, b) |
| 170 | if err != nil { |
| 171 | return "", err |
| 172 | } |
| 173 | |
| 174 | return util.BytesToString(b[:replyLen]), nil |
| 175 | } |
| 176 | |
| 177 | func (r *Reader) ReadArrayReply(m MultiBulkParse) (interface{}, error) { |
| 178 | line, err := r.ReadLine() |
| 179 | if err != nil { |
| 180 | return nil, err |
| 181 | } |
| 182 | switch line[0] { |
| 183 | case ErrorReply: |
| 184 | return nil, ParseErrorReply(line) |
| 185 | case ArrayReply: |
| 186 | n, err := parseArrayLen(line) |
| 187 | if err != nil { |
| 188 | return nil, err |
| 189 | } |
| 190 | return m(r, n) |
| 191 | default: |
| 192 | return nil, fmt.Errorf("redis: can't parse array reply: %.100q", line) |
| 193 | } |
| 194 | } |
| 195 | |
| 196 | func (r *Reader) ReadArrayLen() (int, error) { |
| 197 | line, err := r.ReadLine() |
| 198 | if err != nil { |
| 199 | return 0, err |
| 200 | } |
| 201 | switch line[0] { |
| 202 | case ErrorReply: |
| 203 | return 0, ParseErrorReply(line) |
| 204 | case ArrayReply: |
| 205 | n, err := parseArrayLen(line) |
| 206 | if err != nil { |
| 207 | return 0, err |
| 208 | } |
| 209 | return int(n), nil |
| 210 | default: |
| 211 | return 0, fmt.Errorf("redis: can't parse array reply: %.100q", line) |
| 212 | } |
| 213 | } |
| 214 | |
| 215 | func (r *Reader) ReadScanReply() ([]string, uint64, error) { |
| 216 | n, err := r.ReadArrayLen() |
| 217 | if err != nil { |
| 218 | return nil, 0, err |
| 219 | } |
| 220 | if n != 2 { |
| 221 | return nil, 0, fmt.Errorf("redis: got %d elements in scan reply, expected 2", n) |
| 222 | } |
| 223 | |
| 224 | cursor, err := r.ReadUint() |
| 225 | if err != nil { |
| 226 | return nil, 0, err |
| 227 | } |
| 228 | |
| 229 | n, err = r.ReadArrayLen() |
| 230 | if err != nil { |
| 231 | return nil, 0, err |
| 232 | } |
| 233 | |
| 234 | keys := make([]string, n) |
| 235 | |
| 236 | for i := 0; i < n; i++ { |
| 237 | key, err := r.ReadString() |
| 238 | if err != nil { |
| 239 | return nil, 0, err |
| 240 | } |
| 241 | keys[i] = key |
| 242 | } |
| 243 | |
| 244 | return keys, cursor, err |
| 245 | } |
| 246 | |
| 247 | func (r *Reader) ReadInt() (int64, error) { |
| 248 | b, err := r.readTmpBytesReply() |
| 249 | if err != nil { |
| 250 | return 0, err |
| 251 | } |
| 252 | return util.ParseInt(b, 10, 64) |
| 253 | } |
| 254 | |
| 255 | func (r *Reader) ReadUint() (uint64, error) { |
| 256 | b, err := r.readTmpBytesReply() |
| 257 | if err != nil { |
| 258 | return 0, err |
| 259 | } |
| 260 | return util.ParseUint(b, 10, 64) |
| 261 | } |
| 262 | |
| 263 | func (r *Reader) ReadFloatReply() (float64, error) { |
| 264 | b, err := r.readTmpBytesReply() |
| 265 | if err != nil { |
| 266 | return 0, err |
| 267 | } |
| 268 | return util.ParseFloat(b, 64) |
| 269 | } |
| 270 | |
| 271 | func (r *Reader) readTmpBytesReply() ([]byte, error) { |
| 272 | line, err := r.ReadLine() |
| 273 | if err != nil { |
| 274 | return nil, err |
| 275 | } |
| 276 | switch line[0] { |
| 277 | case ErrorReply: |
| 278 | return nil, ParseErrorReply(line) |
| 279 | case StringReply: |
| 280 | return r._readTmpBytesReply(line) |
| 281 | case StatusReply: |
| 282 | return line[1:], nil |
| 283 | default: |
| 284 | return nil, fmt.Errorf("redis: can't parse string reply: %.100q", line) |
| 285 | } |
| 286 | } |
| 287 | |
| 288 | func (r *Reader) _readTmpBytesReply(line []byte) ([]byte, error) { |
| 289 | if isNilReply(line) { |
| 290 | return nil, Nil |
| 291 | } |
| 292 | |
| 293 | replyLen, err := util.Atoi(line[1:]) |
| 294 | if err != nil { |
| 295 | return nil, err |
| 296 | } |
| 297 | |
| 298 | buf := r.buf(replyLen + 2) |
| 299 | _, err = io.ReadFull(r.rd, buf) |
| 300 | if err != nil { |
| 301 | return nil, err |
| 302 | } |
| 303 | |
| 304 | return buf[:replyLen], nil |
| 305 | } |
| 306 | |
| 307 | func (r *Reader) buf(n int) []byte { |
| 308 | if n <= cap(r._buf) { |
| 309 | return r._buf[:n] |
| 310 | } |
| 311 | d := n - cap(r._buf) |
| 312 | r._buf = append(r._buf, make([]byte, d)...) |
| 313 | return r._buf |
| 314 | } |
| 315 | |
| 316 | func isNilReply(b []byte) bool { |
| 317 | return len(b) == 3 && |
| 318 | (b[0] == StringReply || b[0] == ArrayReply) && |
| 319 | b[1] == '-' && b[2] == '1' |
| 320 | } |
| 321 | |
| 322 | func ParseErrorReply(line []byte) error { |
| 323 | return RedisError(string(line[1:])) |
| 324 | } |
| 325 | |
| 326 | func parseArrayLen(line []byte) (int64, error) { |
| 327 | if isNilReply(line) { |
| 328 | return 0, Nil |
| 329 | } |
| 330 | return util.ParseInt(line[1:], 10, 64) |
| 331 | } |