README.md

MPT - Modified Merkle Patricia Tries

Simple implementation of Modified Merkle Patricia Tries on GoLang.

Usage

1. Create the Trie:

   • With empty root node:

   trie := mpt.NewEmptyTrie()

   • With branch root node:

   nd := node.NewBranchNode()
   trie := mpt.NewTrie(nd)

   • With extension root node:

   nd := node.NewExtensionNode(nil, nil)
   trie := mpt.NewTrie(nd)

2. Add key/value pair:

key := []byte("key")
val := []byte("val")

// create new trie and try add key/value pair
trie := mpt.NewEmptyTrie()
if ok := trie.Put(key, val); !ok {
	// key/pair not added
}

3. Get data by key:

key := []byte("key")
val := []byte("val")

// create new trie and try add key/value pair
trie := mpt.NewEmptyTrie()
if ok := trie.Put(key, val); !ok {
	// key/pair not added
}

// some logic...

// try to get data by key
getVal, ok := trie.Get(key)
if !ok {
	// key/pair not added
}

4. Update data by key:

// initialize data
key := []byte("key")
val := []byte("val")

// create new trie and try add key/value pair
trie := mpt.NewEmptyTrie()
if ok := trie.Put(key, val); !ok {
	// key/pair not added
}

// some logic...

// try to update value by key
newVal := []byte("updated value")
if ok := trie.Update(key, newVal); !ok {
	// data not updated
}

5. Delete data by key:

// initialize data
key := []byte("key")
val := []byte("val")

// create new trie and try add key/value pair
trie := mpt.NewEmptyTrie()
if ok := trie.Put(key, val); !ok {
	// key/pair not added
}

// some logic...

// try to delete data by key
if ok := trie.Delete(key, newVal); !ok {
	// data not deleted
}

6. Get hash of the trie:

// initialize data
key := []byte("key")
val := []byte("val")

// create new trie and try add key/value pair
trie := mpt.NewEmptyTrie()
if ok := trie.Put(key, val); !ok {
	// key/pair not added
}

// some logic...

// try to get hash of the trie
h, err := trie.Hash()
if err != nil {
	// error while hash calculation
}

fmt.Println("hash of the trie:", h)

Benchmarks

Name	Iterations	Time	Description
BenchmarkTrie_Get/FromFullTrie100000-4	1000000	3463 ns/op	Get data from the tree which have 100000 key/value pairs
BenchmarkTrie_Get/FromEmptyTrie-4	1000000	1262 ns/op	Get data from the empty tree
BenchmarkTrie_Put/ToFullTrie100000-4	3000000	513 ns/op	Put data to the tree which have 100000 key/value pairs
BenchmarkTrie_Put/ToEmptyTrie-4	3000000	524 ns/op	Put data to empty tree
BenchmarkTrie_Update/FullTrie100000-4	1000000	3083 ns/op	Update data in the tree which have 100000 key/value pairs
BenchmarkTrie_Update/EmptyTrie-4	2000000	674 ns/op	Update data in empty tree

Backlog

• Implement Database layer - need for store tree