khenaidoo | ffe076b | 2019-01-15 16:08:08 -0500 | [diff] [blame^] | 1 | // Copyright 2017 The etcd Authors |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | package namespace |
| 16 | |
| 17 | import ( |
| 18 | "context" |
| 19 | |
| 20 | "github.com/coreos/etcd/clientv3" |
| 21 | "github.com/coreos/etcd/etcdserver/api/v3rpc/rpctypes" |
| 22 | pb "github.com/coreos/etcd/etcdserver/etcdserverpb" |
| 23 | ) |
| 24 | |
| 25 | type kvPrefix struct { |
| 26 | clientv3.KV |
| 27 | pfx string |
| 28 | } |
| 29 | |
| 30 | // NewKV wraps a KV instance so that all requests |
| 31 | // are prefixed with a given string. |
| 32 | func NewKV(kv clientv3.KV, prefix string) clientv3.KV { |
| 33 | return &kvPrefix{kv, prefix} |
| 34 | } |
| 35 | |
| 36 | func (kv *kvPrefix) Put(ctx context.Context, key, val string, opts ...clientv3.OpOption) (*clientv3.PutResponse, error) { |
| 37 | if len(key) == 0 { |
| 38 | return nil, rpctypes.ErrEmptyKey |
| 39 | } |
| 40 | op := kv.prefixOp(clientv3.OpPut(key, val, opts...)) |
| 41 | r, err := kv.KV.Do(ctx, op) |
| 42 | if err != nil { |
| 43 | return nil, err |
| 44 | } |
| 45 | put := r.Put() |
| 46 | kv.unprefixPutResponse(put) |
| 47 | return put, nil |
| 48 | } |
| 49 | |
| 50 | func (kv *kvPrefix) Get(ctx context.Context, key string, opts ...clientv3.OpOption) (*clientv3.GetResponse, error) { |
| 51 | if len(key) == 0 { |
| 52 | return nil, rpctypes.ErrEmptyKey |
| 53 | } |
| 54 | r, err := kv.KV.Do(ctx, kv.prefixOp(clientv3.OpGet(key, opts...))) |
| 55 | if err != nil { |
| 56 | return nil, err |
| 57 | } |
| 58 | get := r.Get() |
| 59 | kv.unprefixGetResponse(get) |
| 60 | return get, nil |
| 61 | } |
| 62 | |
| 63 | func (kv *kvPrefix) Delete(ctx context.Context, key string, opts ...clientv3.OpOption) (*clientv3.DeleteResponse, error) { |
| 64 | if len(key) == 0 { |
| 65 | return nil, rpctypes.ErrEmptyKey |
| 66 | } |
| 67 | r, err := kv.KV.Do(ctx, kv.prefixOp(clientv3.OpDelete(key, opts...))) |
| 68 | if err != nil { |
| 69 | return nil, err |
| 70 | } |
| 71 | del := r.Del() |
| 72 | kv.unprefixDeleteResponse(del) |
| 73 | return del, nil |
| 74 | } |
| 75 | |
| 76 | func (kv *kvPrefix) Do(ctx context.Context, op clientv3.Op) (clientv3.OpResponse, error) { |
| 77 | if len(op.KeyBytes()) == 0 && !op.IsTxn() { |
| 78 | return clientv3.OpResponse{}, rpctypes.ErrEmptyKey |
| 79 | } |
| 80 | r, err := kv.KV.Do(ctx, kv.prefixOp(op)) |
| 81 | if err != nil { |
| 82 | return r, err |
| 83 | } |
| 84 | switch { |
| 85 | case r.Get() != nil: |
| 86 | kv.unprefixGetResponse(r.Get()) |
| 87 | case r.Put() != nil: |
| 88 | kv.unprefixPutResponse(r.Put()) |
| 89 | case r.Del() != nil: |
| 90 | kv.unprefixDeleteResponse(r.Del()) |
| 91 | case r.Txn() != nil: |
| 92 | kv.unprefixTxnResponse(r.Txn()) |
| 93 | } |
| 94 | return r, nil |
| 95 | } |
| 96 | |
| 97 | type txnPrefix struct { |
| 98 | clientv3.Txn |
| 99 | kv *kvPrefix |
| 100 | } |
| 101 | |
| 102 | func (kv *kvPrefix) Txn(ctx context.Context) clientv3.Txn { |
| 103 | return &txnPrefix{kv.KV.Txn(ctx), kv} |
| 104 | } |
| 105 | |
| 106 | func (txn *txnPrefix) If(cs ...clientv3.Cmp) clientv3.Txn { |
| 107 | txn.Txn = txn.Txn.If(txn.kv.prefixCmps(cs)...) |
| 108 | return txn |
| 109 | } |
| 110 | |
| 111 | func (txn *txnPrefix) Then(ops ...clientv3.Op) clientv3.Txn { |
| 112 | txn.Txn = txn.Txn.Then(txn.kv.prefixOps(ops)...) |
| 113 | return txn |
| 114 | } |
| 115 | |
| 116 | func (txn *txnPrefix) Else(ops ...clientv3.Op) clientv3.Txn { |
| 117 | txn.Txn = txn.Txn.Else(txn.kv.prefixOps(ops)...) |
| 118 | return txn |
| 119 | } |
| 120 | |
| 121 | func (txn *txnPrefix) Commit() (*clientv3.TxnResponse, error) { |
| 122 | resp, err := txn.Txn.Commit() |
| 123 | if err != nil { |
| 124 | return nil, err |
| 125 | } |
| 126 | txn.kv.unprefixTxnResponse(resp) |
| 127 | return resp, nil |
| 128 | } |
| 129 | |
| 130 | func (kv *kvPrefix) prefixOp(op clientv3.Op) clientv3.Op { |
| 131 | if !op.IsTxn() { |
| 132 | begin, end := kv.prefixInterval(op.KeyBytes(), op.RangeBytes()) |
| 133 | op.WithKeyBytes(begin) |
| 134 | op.WithRangeBytes(end) |
| 135 | return op |
| 136 | } |
| 137 | cmps, thenOps, elseOps := op.Txn() |
| 138 | return clientv3.OpTxn(kv.prefixCmps(cmps), kv.prefixOps(thenOps), kv.prefixOps(elseOps)) |
| 139 | } |
| 140 | |
| 141 | func (kv *kvPrefix) unprefixGetResponse(resp *clientv3.GetResponse) { |
| 142 | for i := range resp.Kvs { |
| 143 | resp.Kvs[i].Key = resp.Kvs[i].Key[len(kv.pfx):] |
| 144 | } |
| 145 | } |
| 146 | |
| 147 | func (kv *kvPrefix) unprefixPutResponse(resp *clientv3.PutResponse) { |
| 148 | if resp.PrevKv != nil { |
| 149 | resp.PrevKv.Key = resp.PrevKv.Key[len(kv.pfx):] |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | func (kv *kvPrefix) unprefixDeleteResponse(resp *clientv3.DeleteResponse) { |
| 154 | for i := range resp.PrevKvs { |
| 155 | resp.PrevKvs[i].Key = resp.PrevKvs[i].Key[len(kv.pfx):] |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | func (kv *kvPrefix) unprefixTxnResponse(resp *clientv3.TxnResponse) { |
| 160 | for _, r := range resp.Responses { |
| 161 | switch tv := r.Response.(type) { |
| 162 | case *pb.ResponseOp_ResponseRange: |
| 163 | if tv.ResponseRange != nil { |
| 164 | kv.unprefixGetResponse((*clientv3.GetResponse)(tv.ResponseRange)) |
| 165 | } |
| 166 | case *pb.ResponseOp_ResponsePut: |
| 167 | if tv.ResponsePut != nil { |
| 168 | kv.unprefixPutResponse((*clientv3.PutResponse)(tv.ResponsePut)) |
| 169 | } |
| 170 | case *pb.ResponseOp_ResponseDeleteRange: |
| 171 | if tv.ResponseDeleteRange != nil { |
| 172 | kv.unprefixDeleteResponse((*clientv3.DeleteResponse)(tv.ResponseDeleteRange)) |
| 173 | } |
| 174 | case *pb.ResponseOp_ResponseTxn: |
| 175 | if tv.ResponseTxn != nil { |
| 176 | kv.unprefixTxnResponse((*clientv3.TxnResponse)(tv.ResponseTxn)) |
| 177 | } |
| 178 | default: |
| 179 | } |
| 180 | } |
| 181 | } |
| 182 | |
| 183 | func (kv *kvPrefix) prefixInterval(key, end []byte) (pfxKey []byte, pfxEnd []byte) { |
| 184 | return prefixInterval(kv.pfx, key, end) |
| 185 | } |
| 186 | |
| 187 | func (kv *kvPrefix) prefixCmps(cs []clientv3.Cmp) []clientv3.Cmp { |
| 188 | newCmps := make([]clientv3.Cmp, len(cs)) |
| 189 | for i := range cs { |
| 190 | newCmps[i] = cs[i] |
| 191 | pfxKey, endKey := kv.prefixInterval(cs[i].KeyBytes(), cs[i].RangeEnd) |
| 192 | newCmps[i].WithKeyBytes(pfxKey) |
| 193 | if len(cs[i].RangeEnd) != 0 { |
| 194 | newCmps[i].RangeEnd = endKey |
| 195 | } |
| 196 | } |
| 197 | return newCmps |
| 198 | } |
| 199 | |
| 200 | func (kv *kvPrefix) prefixOps(ops []clientv3.Op) []clientv3.Op { |
| 201 | newOps := make([]clientv3.Op, len(ops)) |
| 202 | for i := range ops { |
| 203 | newOps[i] = kv.prefixOp(ops[i]) |
| 204 | } |
| 205 | return newOps |
| 206 | } |