43 lines
899 B
Go
43 lines
899 B
Go
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// Package kvstore contains key-value stores.
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package kvstore
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import (
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"errors"
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"sync"
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)
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// ErrNoSuchKey indicates that there's no value for the given key.
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var ErrNoSuchKey = errors.New("no such key")
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// Memory is an in-memory key-value store.
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type Memory struct {
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// m is the underlying map.
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m map[string][]byte
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// mu provides mutual exclusion
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mu sync.Mutex
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}
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// Get returns the specified key's value. In case of error, the
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// error type is such that errors.Is(err, ErrNoSuchKey).
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func (kvs *Memory) Get(key string) ([]byte, error) {
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kvs.mu.Lock()
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defer kvs.mu.Unlock()
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value, ok := kvs.m[key]
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if !ok {
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return nil, ErrNoSuchKey
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}
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return value, nil
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}
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// Set sets a key into the key-value store
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func (kvs *Memory) Set(key string, value []byte) error {
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kvs.mu.Lock()
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defer kvs.mu.Unlock()
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if kvs.m == nil {
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kvs.m = make(map[string][]byte)
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}
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kvs.m[key] = value
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return nil
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}
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