Notice

We contributed this codebase to hyperledger and repo has been moved to https://github.com/hyperledger/aries-framework-swift
This repo will not be updated.

Aries Framework Swift

Aries Framework Swift is an iOS framework for Aries protocol.

Features

Aries Framework Swift supports most of AIP 1.0 features for mobile agents.

Supported features

✅ (RFC 0160) Connection Protocol
✅ (RFC 0211) Mediator Coordination Protocol
✅ (RFC 0095) Basic Message Protocol
✅ (RFC 0036) Issue Credential Protocol
✅ (RFC 0037) Present Proof Protocol
✅ HTTP & WebSocket Transport
✅ (RFC 0434) Out of Band Protocol (AIP 2.0)

Not supported yet

❌ (RFC 0023) DID Exchange Protocol (AIP 2.0)
❌ (RFC 0035) Report Problem Protocol
❌ (RFC 0056) Service Decorator

Requirements & Installation

Aries Framework Swift requires iOS 15.0+ and distributed as a CocoaPods pod.

Add the following lines at the top of the Podfile:

source 'https://github.com/CocoaPods/Specs.git'
source 'https://github.com/naver/indy-sdk.git'

And add a pod depencency to the Podfile:

pod 'AriesFramework'

Building on Apple silicon Mac is not supported yet.

Usage

App development using Aries Framework Swift is done in following steps:

Create an Agent instance
Create a connection with another agent by receiving a connection invitation
Receive credentials or proof requests by implementing a AgentDelegate

Create an Agent instance

    import AriesFramework

    let config = AgentConfig(walletKey: key,
        genesisPath: genesisPath,
        mediatorConnectionsInvite: mediatorInvitationUrl,
        mediatorPickupStrategy: .Implicit,
        label: "SampleApp",
        autoAcceptCredential: .never,
        autoAcceptProof: .never)

    let agent = Agent(agentConfig: config, agentDelegate: myAgentDelegate)
    try await agent.initialize()

To create an agent, first create a key to encrypt the wallet and save it in the keychain.

    import Indy

    let key = try await IndyWallet.generateKey(forConfig: nil)

A genesis file for the indy pool should be included as a resource in the app bundle and get the path to it.

    let genesisPath = Bundle.main.path(forResource: "genesis", ofType: "txn")

If you want to use a mediator, set the mediatorConnectionsInvite in the config. mediatorConnectionsInvite is a url containing either a connection invitation or an out-of-band invitation. mediatorPickupStrategy need to be .Implicit to connect to an ACA-Py mediator.

You can use WebSocket transport without a mediator, but you will need a mediator if the counterparty agent only supports http transport.

agentDelegate can be nil if you don't want to receive any events from the agent.

Receive an invitation

Create a connection by receiving a connection invitation.

    let (_, connection) = try await agent.oob.receiveInvitationFromUrl(url)

You will generally get the invitation url by QR code scanning. Once the connection is created, it is stored in the wallet and your counterparty agent can send you a credential or a proof request using the connection at any time. The connection record contains keys to encrypt or decrypt messages exchanged through the connection.

Receive credentials or proof requests

Implement AgentDelegate to receive events from the agent and use agent.credentials or agent.proofs commands to handle the requests.

class MyAgentDelegate: AgentDelegate {
    func onCredentialStateChanged(credentialRecord: CredentialExchangeRecord) {
        if credentialRecord.state == .OfferReceived {
            processCredentialOffer(credentialRecord)
        } else if credentialRecord.state == .Done {
            showSimpleAlert(message: "Credential received")
        }
    }

    func onProofStateChanged(proofRecord: ProofExchangeRecord) {
        if proofRecord.state == .RequestReceived {
            processProofRequest(proofRecord)
        } else if proofRecord.state == .Done {
            showSimpleAlert(message: "Proof done")
        }
    }

    func processCredentialOffer(_ credentialRecord: CredentialExchangeRecord) {
        Task {
            do {
                _ = try await agent.credentials.acceptOffer(options: AcceptOfferOptions(credentialRecordId: credentialRecord.id, autoAcceptCredential: .always))
            } catch {
                showSimpleAlert(message: "Failed to receive credential")
                print(error)
            }
        }
    }

    func processProofRequest(_ proofRecord: ProofExchangeRecord) {
        Task {
            do {
                let retrievedCredentials = try await agent.proofs.getRequestedCredentialsForProofRequest(proofRecordId: proofRecord.id)
                let requestedCredentials = try await agent.proofService.autoSelectCredentialsForProofRequest(retrievedCredentials: retrievedCredentials)
                _ = try await agent!.proofs.acceptRequest(proofRecordId: proofRecord.id, requestedCredentials: requestedCredentials)
            } catch {
                showSimpleAlert(message: "Failed to present proof")
                print(error)
            }
        }
    }
}

If you set autoAcceptCredential and autoAcceptProof to .always in the config, it will be done automatically and you don't need to implement a delegate.

Another way to handle those requests is to implement your own MessageHandler class and register it to the agent.

    let messageHandler = MyOfferCredentialHandler()
    agent.dispatcher.registerHandler(handler: messageHandler)

For your information, Aries Framework Swift refers to Aries Framework JavaScript a lot, so the class name and API are almost the same.

Sample App

Sample directory contains an iOS sample app that demonstrates how to use Aries Framework Swift. The app receives a connection invitation from a QR code or from a URL input and handles credential offers and proof requests.

To run the sample app, first install the dependencies using CocoaPods.

$ cd Sample
$ pod install

Then open wallet-app-ios.xcworkspace and run the app. The agent is created in the WalletOpener.swift file and you can set a mediator connection invitation url there, if you want.

There are two genesis files in the resources directory.

bcovrin-genesis.txn is for the GreenLight Dev Ledger
local-genesis.txn is for the local indy-pool.

Contributing

We welcome contributions to Aries Framework Swift. Please see our Developer Guide for more information.

License

Aries Framework Swift is licensed under the Apache License 2.0.

   Copyright (c) 2022-present NAVER Corp.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

naver/aries-framework-swift