Message Exchange

A library for implementing services to support message exchange between DIDComm agents.

Features

| Protocol | Description | Status | | -------------------------------------------------------------------------------------------------- | ------------------------------------------------------ | -------------- | | DIDComm Message Routing | Send a message to a DIDComm agent via their mediators. | ✅ Implemented | | Message Pickup | Pick up messages from mediators. | ✅ Implemented |

Installation

npm install @adorsys-gis/message-exchange

Usage

Prerequisites

Before using the library, you'll need a DID address for the sending party. This can be created using the DIDIdentityService from the peer library @adorsys-gis/multiple-did-identities. Here's an example of generating a DID using that library:

export const generateIdentity = async (secretPinNumber: number) => {
  const createEvent = waitForEvent(DidEventChannel.CreateDidIdentity);

  didIdentityService.createDidIdentity(
    DIDMethodName.Peer,
    secretPinNumber,
    PeerGenerationMethod.Method2,
  );

  const data = (await createEvent) as ServiceResponse<{ did: string }>;
  return data.payload.did;
};

Once you have the senderDid, you can send messages using the MessageExchangeService.

Using the MessageExchangeService

The MessageExchangeService is designed to work seamlessly with an event bus architecture. Here's how to send a message from a sender to a recipient:

import { MessageExchangeService } from '@adorsys-gis/message-exchange';
import { MessageExchangeEvent } from '@adorsys-gis/message-exchange';

const messageExchangeService = new MessageExchangeService(
  eventBus,
  secretPinNumber,
);

// Listen on the MessageExchangeEvent.RouteForwardMessages event

messageExchangeService.routeForwardMessage(message, recipientDid, senderDid);

// Wait for an acknowledgement on MessageExchangeEvent.RouteForwardMessages

Using the MessageRouter Interface

If your application does not use an event bus, you can interact directly with the MessageRouter interface:

import { MessageRouter } from '@adorsys-gis/message-exchange';

const messageRouter = new MessageRouter(
  didRepository,
  messageRepository,
  secretPinNumber,
);

const sentMessage = await messageRouter.routeForwardMessage(
  message,
  recipientDid,
  senderDid,
);

Additional Help

For more examples and detailed scenarios, consider referring to the test cases in the project.