| // Copyright 2017 The etcd Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package namespace |
| |
| import ( |
| "context" |
| |
| "github.com/coreos/etcd/clientv3" |
| "github.com/coreos/etcd/etcdserver/api/v3rpc/rpctypes" |
| pb "github.com/coreos/etcd/etcdserver/etcdserverpb" |
| ) |
| |
| type kvPrefix struct { |
| clientv3.KV |
| pfx string |
| } |
| |
| // NewKV wraps a KV instance so that all requests |
| // are prefixed with a given string. |
| func NewKV(kv clientv3.KV, prefix string) clientv3.KV { |
| return &kvPrefix{kv, prefix} |
| } |
| |
| func (kv *kvPrefix) Put(ctx context.Context, key, val string, opts ...clientv3.OpOption) (*clientv3.PutResponse, error) { |
| if len(key) == 0 { |
| return nil, rpctypes.ErrEmptyKey |
| } |
| op := kv.prefixOp(clientv3.OpPut(key, val, opts...)) |
| r, err := kv.KV.Do(ctx, op) |
| if err != nil { |
| return nil, err |
| } |
| put := r.Put() |
| kv.unprefixPutResponse(put) |
| return put, nil |
| } |
| |
| func (kv *kvPrefix) Get(ctx context.Context, key string, opts ...clientv3.OpOption) (*clientv3.GetResponse, error) { |
| if len(key) == 0 { |
| return nil, rpctypes.ErrEmptyKey |
| } |
| r, err := kv.KV.Do(ctx, kv.prefixOp(clientv3.OpGet(key, opts...))) |
| if err != nil { |
| return nil, err |
| } |
| get := r.Get() |
| kv.unprefixGetResponse(get) |
| return get, nil |
| } |
| |
| func (kv *kvPrefix) Delete(ctx context.Context, key string, opts ...clientv3.OpOption) (*clientv3.DeleteResponse, error) { |
| if len(key) == 0 { |
| return nil, rpctypes.ErrEmptyKey |
| } |
| r, err := kv.KV.Do(ctx, kv.prefixOp(clientv3.OpDelete(key, opts...))) |
| if err != nil { |
| return nil, err |
| } |
| del := r.Del() |
| kv.unprefixDeleteResponse(del) |
| return del, nil |
| } |
| |
| func (kv *kvPrefix) Do(ctx context.Context, op clientv3.Op) (clientv3.OpResponse, error) { |
| if len(op.KeyBytes()) == 0 && !op.IsTxn() { |
| return clientv3.OpResponse{}, rpctypes.ErrEmptyKey |
| } |
| r, err := kv.KV.Do(ctx, kv.prefixOp(op)) |
| if err != nil { |
| return r, err |
| } |
| switch { |
| case r.Get() != nil: |
| kv.unprefixGetResponse(r.Get()) |
| case r.Put() != nil: |
| kv.unprefixPutResponse(r.Put()) |
| case r.Del() != nil: |
| kv.unprefixDeleteResponse(r.Del()) |
| case r.Txn() != nil: |
| kv.unprefixTxnResponse(r.Txn()) |
| } |
| return r, nil |
| } |
| |
| type txnPrefix struct { |
| clientv3.Txn |
| kv *kvPrefix |
| } |
| |
| func (kv *kvPrefix) Txn(ctx context.Context) clientv3.Txn { |
| return &txnPrefix{kv.KV.Txn(ctx), kv} |
| } |
| |
| func (txn *txnPrefix) If(cs ...clientv3.Cmp) clientv3.Txn { |
| txn.Txn = txn.Txn.If(txn.kv.prefixCmps(cs)...) |
| return txn |
| } |
| |
| func (txn *txnPrefix) Then(ops ...clientv3.Op) clientv3.Txn { |
| txn.Txn = txn.Txn.Then(txn.kv.prefixOps(ops)...) |
| return txn |
| } |
| |
| func (txn *txnPrefix) Else(ops ...clientv3.Op) clientv3.Txn { |
| txn.Txn = txn.Txn.Else(txn.kv.prefixOps(ops)...) |
| return txn |
| } |
| |
| func (txn *txnPrefix) Commit() (*clientv3.TxnResponse, error) { |
| resp, err := txn.Txn.Commit() |
| if err != nil { |
| return nil, err |
| } |
| txn.kv.unprefixTxnResponse(resp) |
| return resp, nil |
| } |
| |
| func (kv *kvPrefix) prefixOp(op clientv3.Op) clientv3.Op { |
| if !op.IsTxn() { |
| begin, end := kv.prefixInterval(op.KeyBytes(), op.RangeBytes()) |
| op.WithKeyBytes(begin) |
| op.WithRangeBytes(end) |
| return op |
| } |
| cmps, thenOps, elseOps := op.Txn() |
| return clientv3.OpTxn(kv.prefixCmps(cmps), kv.prefixOps(thenOps), kv.prefixOps(elseOps)) |
| } |
| |
| func (kv *kvPrefix) unprefixGetResponse(resp *clientv3.GetResponse) { |
| for i := range resp.Kvs { |
| resp.Kvs[i].Key = resp.Kvs[i].Key[len(kv.pfx):] |
| } |
| } |
| |
| func (kv *kvPrefix) unprefixPutResponse(resp *clientv3.PutResponse) { |
| if resp.PrevKv != nil { |
| resp.PrevKv.Key = resp.PrevKv.Key[len(kv.pfx):] |
| } |
| } |
| |
| func (kv *kvPrefix) unprefixDeleteResponse(resp *clientv3.DeleteResponse) { |
| for i := range resp.PrevKvs { |
| resp.PrevKvs[i].Key = resp.PrevKvs[i].Key[len(kv.pfx):] |
| } |
| } |
| |
| func (kv *kvPrefix) unprefixTxnResponse(resp *clientv3.TxnResponse) { |
| for _, r := range resp.Responses { |
| switch tv := r.Response.(type) { |
| case *pb.ResponseOp_ResponseRange: |
| if tv.ResponseRange != nil { |
| kv.unprefixGetResponse((*clientv3.GetResponse)(tv.ResponseRange)) |
| } |
| case *pb.ResponseOp_ResponsePut: |
| if tv.ResponsePut != nil { |
| kv.unprefixPutResponse((*clientv3.PutResponse)(tv.ResponsePut)) |
| } |
| case *pb.ResponseOp_ResponseDeleteRange: |
| if tv.ResponseDeleteRange != nil { |
| kv.unprefixDeleteResponse((*clientv3.DeleteResponse)(tv.ResponseDeleteRange)) |
| } |
| case *pb.ResponseOp_ResponseTxn: |
| if tv.ResponseTxn != nil { |
| kv.unprefixTxnResponse((*clientv3.TxnResponse)(tv.ResponseTxn)) |
| } |
| default: |
| } |
| } |
| } |
| |
| func (kv *kvPrefix) prefixInterval(key, end []byte) (pfxKey []byte, pfxEnd []byte) { |
| return prefixInterval(kv.pfx, key, end) |
| } |
| |
| func (kv *kvPrefix) prefixCmps(cs []clientv3.Cmp) []clientv3.Cmp { |
| newCmps := make([]clientv3.Cmp, len(cs)) |
| for i := range cs { |
| newCmps[i] = cs[i] |
| pfxKey, endKey := kv.prefixInterval(cs[i].KeyBytes(), cs[i].RangeEnd) |
| newCmps[i].WithKeyBytes(pfxKey) |
| if len(cs[i].RangeEnd) != 0 { |
| newCmps[i].RangeEnd = endKey |
| } |
| } |
| return newCmps |
| } |
| |
| func (kv *kvPrefix) prefixOps(ops []clientv3.Op) []clientv3.Op { |
| newOps := make([]clientv3.Op, len(ops)) |
| for i := range ops { |
| newOps[i] = kv.prefixOp(ops[i]) |
| } |
| return newOps |
| } |