[query] Update /database/create endpoint to support creating an aggre…

…gated namespace (#2670)

src/cluster/kv/fake/store.go

@@ -0,0 +1,156 @@
+// Copyright (c) 2020  Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package fake
+
+import (
+	"errors"
+
+	"github.com/m3db/m3/src/cluster/kv"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// NewStore returns a fakeStore adhering to the kv.Store interface.
+// All methods except Watch are implemented. Implementation is not threadsafe
+// and should only be used for tests.
+func NewStore() kv.Store {
+	return &fakeStore{
+		store: make(map[string][]kv.Value),
+	}
+}
+
+type fakeStore struct {
+	store map[string][]kv.Value
+}
+
+func (f *fakeStore) Get(key string) (kv.Value, error) {
+	value, ok := f.store[key]
+	if !ok {
+		return nil, kv.ErrNotFound
+	}
+
+	return value[len(value)-1], nil
+}
+
+func (f *fakeStore) Watch(_ string) (kv.ValueWatch, error) {
+	panic("implement me")
+}
+
+func (f *fakeStore) Set(key string, v proto.Message) (int, error) {
+	oldVal, err := f.Get(key)
+	if err != nil && err != kv.ErrNotFound {
+		return 0, err
+	}
+
+	data, err := proto.Marshal(v)
+	if err != nil {
+		return 0, err
+	}
+
+	var newVer int
+	if oldVal == nil {
+		f.store[key] = []kv.Value{newValue(data, int64(newVer))}
+	} else {
+		newVer = oldVal.Version() + 1
+		f.store[key] = append(f.store[key], newValue(data, int64(newVer)))
+	}
+
+	return newVer, nil
+}
+
+func (f *fakeStore) SetIfNotExists(key string, v proto.Message) (int, error) {
+	_, err := f.Get(key)
+	if err == kv.ErrNotFound {
+		return f.Set(key, v)
+	} else {
+		return 0, kv.ErrAlreadyExists
+	}
+}
+
+func (f *fakeStore) CheckAndSet(key string, version int, v proto.Message) (int, error) {
+	val, err := f.Get(key)
+	if err != nil && err != kv.ErrNotFound {
+		return 0, err
+	} else if err != nil && err == kv.ErrNotFound && version == 0 {
+		return f.Set(key, v)
+	} else if val == nil {
+		return 0, kv.ErrVersionMismatch
+	} else if val.Version() == version {
+		return f.Set(key, v)
+	} else {
+		return 0, kv.ErrVersionMismatch
+	}
+}
+
+func (f *fakeStore) Delete(key string) (kv.Value, error) {
+	val, err := f.Get(key)
+	if err != nil {
+		return nil, err
+	}
+	delete(f.store, key)
+
+	return val, nil
+}
+
+func (f *fakeStore) History(key string, from, to int) ([]kv.Value, error) {
+	if from > to || from < 0 || to < 0 {
+		return nil, errors.New("invalid history range")
+	}
+
+	if from == to {
+		return nil, nil
+	}
+
+	vals, ok := f.store[key]
+	if !ok {
+		return nil, kv.ErrNotFound
+	}
+	if to > len(vals) {
+		return nil, errors.New("invalid history range")
+	}
+
+	return vals[from:to], nil
+}
+
+type value struct {
+	Val []byte
+	Ver int64
+}
+
+func newValue(val []byte, ver int64) *value {
+	return &value{
+		Val: val,
+		Ver: ver,
+	}
+}
+
+func (c *value) IsNewer(other kv.Value) bool {
+	return c.Version() > other.Version()
+}
+
+func (c *value) Unmarshal(v proto.Message) error {
+	err := proto.Unmarshal(c.Val, v)
+	return err
+}
+
+func (c *value) Version() int {
+	return int(c.Ver)
+}