Class VerifiableCredential

constructor

• new VerifiableCredential(vcDataModel): VerifiableCredential

• Parameters

  • vcDataModel: ICredential

  Returns VerifiableCredential

vcDataModel

issuer

• get issuer(): string

• The issuer of the credential.

  Returns string

subject

• get subject(): string

• The subject of the credential.

  Returns string

type

• get type(): string

• The type of the credential.

  Returns string

sign

• sign(options): Promise<string>

• Signs the verifiable credential and returns it as a signed JWT.

  Parameters

  • options: VerifiableCredentialSignOptions

    The sign options used to sign the credential.

  Returns Promise<string>

  The JWT representing the signed verifiable credential.

  Example

  const vcJwt = verifiableCredential.sign({ did: myDid });
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toString

• toString(): string

• Converts the current object to its JSON representation.

  Returns string

  The JSON representation of the object.

Static create

• create(options): Promise<VerifiableCredential>

• Create a [VerifiableCredential] based on the provided parameters.

  Parameters

  • options: VerifiableCredentialCreateOptions

    The options to use when creating the Verifiable Credential.

  Returns Promise<VerifiableCredential>

  A [VerifiableCredential] instance.

  Example

  const vc = await VerifiableCredential.create({
      type: 'StreetCredibility',
      issuer: 'did:ex:issuer',
      subject: 'did:ex:subject',
      data: { 'arbitrary': 'data' }
    })
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Static parseJwt

• parseJwt(vcJwt): VerifiableCredential

• Parses a JWT into a [VerifiableCredential] instance.

  Parameters

  • vcJwt: {
        vcJwt: string;
    }

    The verifiable credential JWT as a [String].

    • vcJwt: string

  Returns VerifiableCredential

  A [VerifiableCredential] instance derived from the JWT.

  Example

  const vc = VerifiableCredential.parseJwt({ vcJwt: signedVcJwt })
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Static verify

• verify(param): Promise<{
      issuer: string;
      subject: string;
      vc: ICredential;
  }>

• Verifies the integrity and authenticity of a Verifiable Credential (VC) encoded as a JSON Web Token (JWT).

  This function performs several crucial validation steps to ensure the trustworthiness of the provided VC:

  • Parses and validates the structure of the JWT.
  • Ensures the presence of critical header elements alg and kid in the JWT header.
  • Resolves the Decentralized Identifier (DID) and retrieves the associated DID Document.
  • Validates the DID and establishes a set of valid verification method IDs.
  • Identifies the correct Verification Method from the DID Document based on the kid parameter.
  • Verifies the JWT's signature using the public key associated with the Verification Method.

  If any of these steps fail, the function will throw a [Error] with a message indicating the nature of the failure:

  • exp MUST represent the expirationDate property, encoded as a UNIX timestamp (NumericDate).
  • iss MUST represent the issuer property of a verifiable credential or the holder property of a verifiable presentation.
  • nbf MUST represent issuanceDate, encoded as a UNIX timestamp (NumericDate).
  • jti MUST represent the id property of the verifiable credential or verifiable presentation.
  • sub MUST represent the id property contained in the credentialSubject.

  Once the verifications are successful, when recreating the VC data model object, this function will:

  • If exp is present, the UNIX timestamp MUST be converted to an [XMLSCHEMA11-2] date-time, and MUST be used to set the value of the expirationDate property of credentialSubject of the new JSON object.
  • If iss is present, the value MUST be used to set the issuer property of the new credential JSON object or the holder property of the new presentation JSON object.
  • If nbf is present, the UNIX timestamp MUST be converted to an [XMLSCHEMA11-2] date-time, and MUST be used to set the value of the issuanceDate property of the new JSON object.
  • If sub is present, the value MUST be used to set the value of the id property of credentialSubject of the new credential JSON object.
  • If jti is present, the value MUST be used to set the value of the id property of the new JSON object.

  Parameters

  • param: {
        vcJwt: string;
    }

    The parameters for the verification process.

    • vcJwt: string

      The Verifiable Credential in JWT format as a [string].

  Returns Promise<{
      issuer: string;
      subject: string;
      vc: ICredential;
  }>

  Example

  try {
      VerifiableCredential.verify({ vcJwt: signedVcJwt })
      console.log("VC Verification successful!")
  } catch (e: Error) {
      console.log("VC Verification failed: ${e.message}")
  }
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  Throws

  Error if the verification fails at any step, providing a message with failure details.

  Throws

  Error if critical JWT header elements are absent.