DID Specification | ERC-1056 | Getting Started
This library conforms to ERC-1056 and is intended to use Ethereum addresses as fully self-managed Decentralized Identifiers (DIDs), it allows you to easily create and manage keys for these identities. It also lets you sign standards compliant JSON Web Tokens (JWT) that can be consumed using the DID-JWT library.
A DID is an Identifier that allows you to lookup a DID document that can be used to authenticate you and messages created by you.
Ethr-DID provides a scalable identity method for Ethereum addresses that gives any Ethereum address the ability to collect on-chain and off-chain data. Because Ethr-DID allows any Ethereum key pair to become an identity, it is more scalable and privacy-preserving than smart contract based identity methods, like our previous Proxy Contract.
This particular DID method relies on the Ethr-Did-Registry. The Ethr-DID-Registry is a smart contract that facilitates public key resolution for off-chain (and on-chain) authentication. It also facilitates key rotation, delegate assignment and revocation to allow 3rd party signers on a key's behalf, as well as setting and revoking off-chain attribute data. These interactions and events are used in aggregate to form a DID's DID document using the Ethr-Did-Resolver.
An example of a DID document resolved using the Ethr-Did-Resolver:
{
'@context': 'https://w3id.org/did/v1',
id: 'did:ethr:0xb9c5714089478a327f09197987f16f9e5d936e8a',
publicKey: [{
id: 'did:ethr:0xb9c5714089478a327f09197987f16f9e5d936e8a#owner',
type: 'Secp256k1VerificationKey2018',
owner: 'did:ethr:0xb9c5714089478a327f09197987f16f9e5d936e8a',
ethereumAddress: '0xb9c5714089478a327f09197987f16f9e5d936e8a'}],
authentication: [{
type: 'Secp256k1SignatureAuthentication2018',
publicKey: 'did:ethr:0xb9c5714089478a327f09197987f16f9e5d936e8a#owner'}]
}
On-chain refers to something that is resolved with a transaction on a blockchain, while off-chain can refer to anything from temporary payment channels to IPFS.
It supports the proposed Decentralized Identifiers spec from the W3C Credentials Community Group.
A "DID method" is a specific implementation of a DID scheme that is identified by a method name
. In this case, the method name is ethr
, and the method identifier is an Ethereum address.
To encode a DID for an Ethereum address, simply prepend did:ethr:
For example:
did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74
import EthrDID from 'ethr-did'
// Assume web3 object is configured either manually or injected using metamask
const ethrDid = new EthrDID({address: '0x...', privateKey: '...', provider})
key | description | required |
---|---|---|
address |
Ethereum address representing Identity | yes |
registry |
registry address (defaults to 0xc1b66dea11f8f321b7981e1666fdaf3637fe0f61 ) |
no |
provider |
web3 provider | no |
web3 |
preconfigured web3 object | no |
rpcUrl |
JSON-RPC endpoint url | no |
signer |
Signing function | either signer or privateKey |
privateKey |
Hex encoded private key | yes* |