go-multihash

multihash implementation in Go

Table of Contents

• Install
• Usage
• Maintainers
• Contribute
• License

Install

go-multihash is a standard Go module which can be installed with:

go get github.com/multiformats/go-multihash

Note that go-multihash is packaged with Gx, so it is recommended to use Gx to install and use it (see Usage section).

Usage

Using Gx and Gx-go

This module is packaged with Gx. In order to use it in your own project it is recommended that you:

go get -u github.com/whyrusleeping/gx
go get -u github.com/whyrusleeping/gx-go
cd <your-project-repository>
gx init
gx import github.com/multiformats/go-multihash
gx install --global
gx-go --rewrite

Please check Gx and Gx-go documentation for more information.

Example

This example takes a standard hex-encoded data and uses EncodeName to calculate the SHA1 multihash value for the buffer.

The resulting hex-encoded data corresponds to: <hash function code><digest size><hash function output>, which could be re-parsed with Multihash.FromHexString().

package main

import (
	"encoding/hex"
	"fmt"

	"github.com/multiformats/go-multihash"
)

func main() {
	// ignores errors for simplicity.
	// don't do that at home.
	// Decode a SHA1 hash to a binary buffer
	buf, _ := hex.DecodeString("0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33")

	// Create a new multihash with it.
	mHashBuf, _ := multihash.EncodeName(buf, "sha1")
	// Print the multihash as hex string
	fmt.Printf("hex: %s\n", hex.EncodeToString(mHashBuf))

	// Parse the binary multihash to a DecodedMultihash
	mHash, _ := multihash.Decode(mHashBuf)
	// Convert the sha1 value to hex string
	sha1hex := hex.EncodeToString(mHash.Digest)
	// Print all the information in the multihash
	fmt.Printf("obj: %v 0x%x %d %s\n", mHash.Name, mHash.Code, mHash.Length, sha1hex)
}

To run, copy to example/foo.go and:

> cd example/
> go build
> ./example
hex: 11140beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33
obj: sha1 0x11 20 0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33

Maintainers

Captain: @Kubuxu.

Contribute

Contributions welcome. Please check out the issues.

Check out our contributing document for more information on how we work, and about contributing in general. Please be aware that all interactions related to multiformats are subject to the IPFS Code of Conduct.

Small note: If editing the README, please conform to the standard-readme specification.

License

MIT © 2014 Juan Batiz-Benet