84 lines
2.3 KiB
Go
84 lines
2.3 KiB
Go
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package etcd
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import (
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"crypto/sha256"
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)
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const (
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bucketIDLength = 32
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)
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var (
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bucketPrefix = []byte("b")
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valuePrefix = []byte("v")
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sequencePrefix = []byte("$")
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)
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// rootBucketId returns a zero filled 32 byte array
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func rootBucketID() []byte {
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var rootID [bucketIDLength]byte
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return rootID[:]
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}
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// makeBucketID returns a deterministic key for the passed byte slice.
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// Currently it returns the sha256 hash of the slice.
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func makeBucketID(key []byte) [bucketIDLength]byte {
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return sha256.Sum256(key)
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}
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// isValidBucketID checks if the passed slice is the required length to be a
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// valid bucket id.
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func isValidBucketID(s []byte) bool {
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return len(s) == bucketIDLength
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}
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// makeKey concatenates prefix, parent and key into one byte slice.
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// The prefix indicates the use of this key (whether bucket, value or sequence),
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// while parentID refers to the parent bucket.
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func makeKey(prefix, parent, key []byte) []byte {
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keyBuf := make([]byte, len(prefix)+len(parent)+len(key))
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copy(keyBuf, prefix)
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copy(keyBuf[len(prefix):], parent)
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copy(keyBuf[len(prefix)+len(parent):], key)
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return keyBuf
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}
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// makePrefix concatenates prefix with parent into one byte slice.
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func makePrefix(prefix []byte, parent []byte) []byte {
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prefixBuf := make([]byte, len(prefix)+len(parent))
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copy(prefixBuf, prefix)
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copy(prefixBuf[len(prefix):], parent)
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return prefixBuf
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}
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// makeBucketKey returns a bucket key from the passed parent bucket id and
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// the key.
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func makeBucketKey(parent []byte, key []byte) []byte {
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return makeKey(bucketPrefix, parent, key)
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}
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// makeValueKey returns a value key from the passed parent bucket id and
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// the key.
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func makeValueKey(parent []byte, key []byte) []byte {
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return makeKey(valuePrefix, parent, key)
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}
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// makeSequenceKey returns a sequence key of the passed parent bucket id.
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func makeSequenceKey(parent []byte) []byte {
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return makeKey(sequencePrefix, parent, nil)
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}
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// makeBucketPrefix returns the bucket prefix of the passed parent bucket id.
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// This prefix is used for all sub buckets.
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func makeBucketPrefix(parent []byte) []byte {
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return makePrefix(bucketPrefix, parent)
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}
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// makeValuePrefix returns the value prefix of the passed parent bucket id.
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// This prefix is used for all key/values in the bucket.
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func makeValuePrefix(parent []byte) []byte {
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return makePrefix(valuePrefix, parent)
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}
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