- new
Identity (privateKey?): Identity Initializes the class attributes based on a given private key, which must be text or a buffer. If the private key is not passed as a parameter, a random private key will be generated. The EdDSAPoseidon class is used to generate the secret scalar and the public key. Additionally, the constructor computes a commitment of the public key using a hash function (Poseidon).

#### Parameters

`Optional`

privateKey: string | Buffer | Uint8ArrayThe private key used to derive the public key (hexadecimal or string).

#### Returns Identity

#### Example

`// Generates an identity.`

const { privateKey, publicKey, commitment } = new Identity("private-key")#### Example

`// Generates an identity with a random private key.`

const { privateKey, publicKey, commitment } = new Identity()

`Private`

_commitment_commitment: bigint

`Private`

_private_privateKey : string | Buffer | Uint8Array

`Private`

_public_publicKey : Point<bigint>

`Private`

_secret_secretScalar : bigint

- get commitment(): bigint
Returns the commitment hash of the public key.

#### Returns bigint

The commitment as a string.

- get privateKey(): string | Buffer | Uint8Array
Returns the private key.

#### Returns string | Buffer | Uint8Array

The private key as a buffer or text.

- get publicKey(): Point<bigint>
Returns the public key as a Baby Jubjub Point.

#### Returns Point<bigint>

The public key as a point.

- get secretScalar(): bigint
Returns the secret scalar.

#### Returns bigint

The secret scalar as a string.

- sign
Message (message): Signature<bigint> Generates a signature for a given message using the private key. This method demonstrates how to sign a message and could be used for authentication or data integrity.

#### Parameters

- message: BigNumberish
The message to be signed.

#### Returns Signature<bigint>

A Signature object containing the signature components.

#### Example

`const identity = new Identity()`

const signature = identity.signMessage("message")- message: BigNumberish

`Static`

import`Static`

verify- verify
Signature (message, signature, publicKey): boolean Verifies a signature against a given message and public key. This static method allows for the verification of signatures without needing an instance of the Identity class. It's useful for cases where you only have the public key, the message and a signature, and need to verify if they match.

#### Parameters

- message: BigNumberish
The message that was signed.

- signature: Signature
The signature to verify.

- publicKey: Point
The public key to use for verification.

#### Returns boolean

A boolean indicating whether the signature is valid.

#### Example

`const identity = new Identity()`

const signature = identity.signMessage("message")

Identity.verifySignature("message", signature, identity.publicKey)- message: BigNumberish

The Semaphore identity is essentially an EdDSA public/private key pair. The EdDSA implementation in this library uses Baby Jubjub for public key generation and Poseidon for signatures. In addition, the commitment, i.e. the hash of the public key, is used to represent Semaphore identities in groups, adding an additional layer of privacy and security. The private key of the identity can be exported as a base64 string.