Pragya Arya | 324337e | 2020-02-20 14:35:08 +0530 | [diff] [blame] | 1 | package sarama |
| 2 | |
| 3 | type fetchRequestBlock struct { |
| 4 | Version int16 |
| 5 | currentLeaderEpoch int32 |
| 6 | fetchOffset int64 |
| 7 | logStartOffset int64 |
| 8 | maxBytes int32 |
| 9 | } |
| 10 | |
| 11 | func (b *fetchRequestBlock) encode(pe packetEncoder, version int16) error { |
| 12 | b.Version = version |
| 13 | if b.Version >= 9 { |
| 14 | pe.putInt32(b.currentLeaderEpoch) |
| 15 | } |
| 16 | pe.putInt64(b.fetchOffset) |
| 17 | if b.Version >= 5 { |
| 18 | pe.putInt64(b.logStartOffset) |
| 19 | } |
| 20 | pe.putInt32(b.maxBytes) |
| 21 | return nil |
| 22 | } |
| 23 | |
| 24 | func (b *fetchRequestBlock) decode(pd packetDecoder, version int16) (err error) { |
| 25 | b.Version = version |
| 26 | if b.Version >= 9 { |
| 27 | if b.currentLeaderEpoch, err = pd.getInt32(); err != nil { |
| 28 | return err |
| 29 | } |
| 30 | } |
| 31 | if b.fetchOffset, err = pd.getInt64(); err != nil { |
| 32 | return err |
| 33 | } |
| 34 | if b.Version >= 5 { |
| 35 | if b.logStartOffset, err = pd.getInt64(); err != nil { |
| 36 | return err |
| 37 | } |
| 38 | } |
| 39 | if b.maxBytes, err = pd.getInt32(); err != nil { |
| 40 | return err |
| 41 | } |
| 42 | return nil |
| 43 | } |
| 44 | |
| 45 | // FetchRequest (API key 1) will fetch Kafka messages. Version 3 introduced the MaxBytes field. See |
| 46 | // https://issues.apache.org/jira/browse/KAFKA-2063 for a discussion of the issues leading up to that. The KIP is at |
| 47 | // https://cwiki.apache.org/confluence/display/KAFKA/KIP-74%3A+Add+Fetch+Response+Size+Limit+in+Bytes |
| 48 | type FetchRequest struct { |
| 49 | MaxWaitTime int32 |
| 50 | MinBytes int32 |
| 51 | MaxBytes int32 |
| 52 | Version int16 |
| 53 | Isolation IsolationLevel |
| 54 | SessionID int32 |
| 55 | SessionEpoch int32 |
| 56 | blocks map[string]map[int32]*fetchRequestBlock |
| 57 | forgotten map[string][]int32 |
| 58 | } |
| 59 | |
| 60 | type IsolationLevel int8 |
| 61 | |
| 62 | const ( |
| 63 | ReadUncommitted IsolationLevel = iota |
| 64 | ReadCommitted |
| 65 | ) |
| 66 | |
| 67 | func (r *FetchRequest) encode(pe packetEncoder) (err error) { |
| 68 | pe.putInt32(-1) // replica ID is always -1 for clients |
| 69 | pe.putInt32(r.MaxWaitTime) |
| 70 | pe.putInt32(r.MinBytes) |
| 71 | if r.Version >= 3 { |
| 72 | pe.putInt32(r.MaxBytes) |
| 73 | } |
| 74 | if r.Version >= 4 { |
| 75 | pe.putInt8(int8(r.Isolation)) |
| 76 | } |
| 77 | if r.Version >= 7 { |
| 78 | pe.putInt32(r.SessionID) |
| 79 | pe.putInt32(r.SessionEpoch) |
| 80 | } |
| 81 | err = pe.putArrayLength(len(r.blocks)) |
| 82 | if err != nil { |
| 83 | return err |
| 84 | } |
| 85 | for topic, blocks := range r.blocks { |
| 86 | err = pe.putString(topic) |
| 87 | if err != nil { |
| 88 | return err |
| 89 | } |
| 90 | err = pe.putArrayLength(len(blocks)) |
| 91 | if err != nil { |
| 92 | return err |
| 93 | } |
| 94 | for partition, block := range blocks { |
| 95 | pe.putInt32(partition) |
| 96 | err = block.encode(pe, r.Version) |
| 97 | if err != nil { |
| 98 | return err |
| 99 | } |
| 100 | } |
| 101 | } |
| 102 | if r.Version >= 7 { |
| 103 | err = pe.putArrayLength(len(r.forgotten)) |
| 104 | if err != nil { |
| 105 | return err |
| 106 | } |
| 107 | for topic, partitions := range r.forgotten { |
| 108 | err = pe.putString(topic) |
| 109 | if err != nil { |
| 110 | return err |
| 111 | } |
| 112 | err = pe.putArrayLength(len(partitions)) |
| 113 | if err != nil { |
| 114 | return err |
| 115 | } |
| 116 | for _, partition := range partitions { |
| 117 | pe.putInt32(partition) |
| 118 | } |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | return nil |
| 123 | } |
| 124 | |
| 125 | func (r *FetchRequest) decode(pd packetDecoder, version int16) (err error) { |
| 126 | r.Version = version |
| 127 | |
| 128 | if _, err = pd.getInt32(); err != nil { |
| 129 | return err |
| 130 | } |
| 131 | if r.MaxWaitTime, err = pd.getInt32(); err != nil { |
| 132 | return err |
| 133 | } |
| 134 | if r.MinBytes, err = pd.getInt32(); err != nil { |
| 135 | return err |
| 136 | } |
| 137 | if r.Version >= 3 { |
| 138 | if r.MaxBytes, err = pd.getInt32(); err != nil { |
| 139 | return err |
| 140 | } |
| 141 | } |
| 142 | if r.Version >= 4 { |
| 143 | isolation, err := pd.getInt8() |
| 144 | if err != nil { |
| 145 | return err |
| 146 | } |
| 147 | r.Isolation = IsolationLevel(isolation) |
| 148 | } |
| 149 | if r.Version >= 7 { |
| 150 | r.SessionID, err = pd.getInt32() |
| 151 | if err != nil { |
| 152 | return err |
| 153 | } |
| 154 | r.SessionEpoch, err = pd.getInt32() |
| 155 | if err != nil { |
| 156 | return err |
| 157 | } |
| 158 | } |
| 159 | topicCount, err := pd.getArrayLength() |
| 160 | if err != nil { |
| 161 | return err |
| 162 | } |
| 163 | if topicCount == 0 { |
| 164 | return nil |
| 165 | } |
| 166 | r.blocks = make(map[string]map[int32]*fetchRequestBlock) |
| 167 | for i := 0; i < topicCount; i++ { |
| 168 | topic, err := pd.getString() |
| 169 | if err != nil { |
| 170 | return err |
| 171 | } |
| 172 | partitionCount, err := pd.getArrayLength() |
| 173 | if err != nil { |
| 174 | return err |
| 175 | } |
| 176 | r.blocks[topic] = make(map[int32]*fetchRequestBlock) |
| 177 | for j := 0; j < partitionCount; j++ { |
| 178 | partition, err := pd.getInt32() |
| 179 | if err != nil { |
| 180 | return err |
| 181 | } |
| 182 | fetchBlock := &fetchRequestBlock{} |
| 183 | if err = fetchBlock.decode(pd, r.Version); err != nil { |
| 184 | return err |
| 185 | } |
| 186 | r.blocks[topic][partition] = fetchBlock |
| 187 | } |
| 188 | } |
| 189 | |
| 190 | if r.Version >= 7 { |
| 191 | forgottenCount, err := pd.getArrayLength() |
| 192 | if err != nil { |
| 193 | return err |
| 194 | } |
| 195 | if forgottenCount == 0 { |
| 196 | return nil |
| 197 | } |
| 198 | r.forgotten = make(map[string][]int32) |
| 199 | for i := 0; i < forgottenCount; i++ { |
| 200 | topic, err := pd.getString() |
| 201 | if err != nil { |
| 202 | return err |
| 203 | } |
| 204 | partitionCount, err := pd.getArrayLength() |
| 205 | if err != nil { |
| 206 | return err |
| 207 | } |
| 208 | r.forgotten[topic] = make([]int32, partitionCount) |
| 209 | |
| 210 | for j := 0; j < partitionCount; j++ { |
| 211 | partition, err := pd.getInt32() |
| 212 | if err != nil { |
| 213 | return err |
| 214 | } |
| 215 | r.forgotten[topic][j] = partition |
| 216 | } |
| 217 | } |
| 218 | } |
| 219 | |
| 220 | return nil |
| 221 | } |
| 222 | |
| 223 | func (r *FetchRequest) key() int16 { |
| 224 | return 1 |
| 225 | } |
| 226 | |
| 227 | func (r *FetchRequest) version() int16 { |
| 228 | return r.Version |
| 229 | } |
| 230 | |
| 231 | func (r *FetchRequest) requiredVersion() KafkaVersion { |
| 232 | switch r.Version { |
| 233 | case 0: |
| 234 | return MinVersion |
| 235 | case 1: |
| 236 | return V0_9_0_0 |
| 237 | case 2: |
| 238 | return V0_10_0_0 |
| 239 | case 3: |
| 240 | return V0_10_1_0 |
| 241 | case 4, 5: |
| 242 | return V0_11_0_0 |
| 243 | case 6: |
| 244 | return V1_0_0_0 |
| 245 | case 7: |
| 246 | return V1_1_0_0 |
| 247 | case 8: |
| 248 | return V2_0_0_0 |
| 249 | case 9, 10: |
| 250 | return V2_1_0_0 |
| 251 | case 11: |
| 252 | return V2_3_0_0 |
| 253 | default: |
| 254 | return MaxVersion |
| 255 | } |
| 256 | } |
| 257 | |
| 258 | func (r *FetchRequest) AddBlock(topic string, partitionID int32, fetchOffset int64, maxBytes int32) { |
| 259 | if r.blocks == nil { |
| 260 | r.blocks = make(map[string]map[int32]*fetchRequestBlock) |
| 261 | } |
| 262 | |
| 263 | if r.Version >= 7 && r.forgotten == nil { |
| 264 | r.forgotten = make(map[string][]int32) |
| 265 | } |
| 266 | |
| 267 | if r.blocks[topic] == nil { |
| 268 | r.blocks[topic] = make(map[int32]*fetchRequestBlock) |
| 269 | } |
| 270 | |
| 271 | tmp := new(fetchRequestBlock) |
| 272 | tmp.Version = r.Version |
| 273 | tmp.maxBytes = maxBytes |
| 274 | tmp.fetchOffset = fetchOffset |
| 275 | if r.Version >= 9 { |
| 276 | tmp.currentLeaderEpoch = int32(-1) |
| 277 | } |
| 278 | |
| 279 | r.blocks[topic][partitionID] = tmp |
| 280 | } |