62 lines
1,015 B
Go
62 lines
1,015 B
Go
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package storage
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import (
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"crypto/sha256"
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)
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type Storage struct {
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Path string
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}
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func NewStorage(path string) (*Storage, error) {
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s := Storage{
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Path: path,
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}
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return &s, nil
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}
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type Object interface {
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GetHash() [32]byte
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}
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type Blob struct {
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Data []byte
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}
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// The `GetHash()` for a `Blob` is a straightforward SHA256 hash of the
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// contents of that blob.
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func (b *Blob) GetHash() [32]byte {
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return sha256.Sum256(b.Data)
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}
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func NewBlob(data []byte) (*Blob, error) {
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b := Blob{
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Data: data,
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}
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return &b, nil
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}
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type Tree struct {
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Items map[string]Object
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}
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func NewTree() (*Tree, error) {
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return nil, nil
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}
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// For a `Tree` the `GetHash()` is a bit more intertwined. It's basically the
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// hash of all its items. Yes, this recurses trees which is bad but the naive
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// approach suffices for now. I also don't like the `[32]` vs `[]` dance here.
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func (t *Tree) GetHash() [32]byte {
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h := sha256.New()
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for _, v := range t.Items {
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s := v.GetHash()
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h.Write(s[:])
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}
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return [32]byte(h.Sum(nil))
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}
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