# OCM Engine

- [Introduction](#introduction)
- [Requirements](#requirements)
- [Architecture](#architecture)
- [Setup](#setup)
- [Local env](#local)
- [Docker env](#docker)
- [Usage](#usage-via-postman)
- [Example](#send-didcomm-messages-between-two-ocms)

## Introduction

OCM Engine is a monorepo based on [NestJS](http://nestjs.com) and [Nx](https://nx.dev), holding applications in `apps` directory and `libraries` in `libs`, which were used to create the applications and can be used for developing additional applications in `OCM` project. 

### Apps list:
    - Agent
    - Attestation Manager
    - Connection Manager
    - Proof Manager
    - Gateway

### Library list:
    - Askar
    - Clients
    - Config
    - Dtos 
    - Ledgers
    - Nats

## Requirements

- Git
- NodeJS >= v18.16.0
- PostgresDB
- Nats

## Architecture

```mermaid
flowchart TD
  Postman --http--> Gateway
  Gateway --ws--> Postman
  Gateway  --tcp-->  cm[Connection Manager] & am[Attestation Manager] & pm[Proof Manager] --event-->  nats[NATS]
  nats --event--> Agent
  Agent --tcp--> Gateway
  Agent <--> db[(PostgresDB)]
  Agent <--> Ledger[(Ledger)]
```

## Setup

- ##### Install Git

  How to install [Git](https://www.atlassian.com/git/tutorials/install-git) on my system.

- ##### Install NodeJS >= v18.16.0 version

  How to install [NodeJS](https://nodejs.org/en/download/package-manager) on my system.
  Second option is to use version manager like [nvm](https://github.com/nvm-sh/nvm) which will allow you to switch between different NodeJS versions.

- ##### Clone the repo

  Once you have installed all Git, Node, Yarn you can clone the project with:

  ```
  git clone git@code.vereign.com:gaiax/ocm/ocm-engine.git
  ```
  or 

  ```
  git clone https://code.vereign.com/gaiax/ocm/ocm-engine.git
  ```


- ##### Install Dependencies

  Go inside your cloned repo and install all dependencies with:
  ```
  yarn install
  ```
  
## Local
  You can run the entire stack or specific application locally.

  Example for entire stack:

    1. copy .env.example to .env
    2. edit .env to your liking 
    3. yarn install
    4. yarn infra:local or install PostgresDB and Nats broker locally and add them to .env
    5. yarn serve:all

  Example of running only the agent service as a rest service.

    1. copy .env.example to .env
    2. edit .env to your liking and change AGENT_IS_REST to true 
    3. yarn install
    4. yarn infra:local or isntall PostgresDB and Nats broker locally and add them to .env
    5. yarn serve:agent

## Docker

Example:

   You can `issuer` OCM stack with: 
    
    1. edit  issuer.env in compose directory
    2. yarn infra:issuer

    Then the gateway will be at http://localhost:8081 url

   `Holder` OCM stack can be started with:
    
    1. edit holder.env in compose directory
    2. yarn infra:holder

    Then the gateway will be at http://localhost:8082 url

   You can run the entire stack - `issuer` and `holder` with:
    
    1. edit issuer.env and holder.env in compose directory
    2. yarn infra

 Yarn commands are wrapper around docker-compose for easier use. You can still use docker-compose from compose dir.

## Usage via Postman
  1. Import postman collection from the  repo
  2. Connect to Web Socket on the gateway address, to listen for responses
  3. Make a request
  4. Response will be sent to the Web Socket

## Send Didcomm messages between two OCMs

1. Setup [Postman](#usage-via-postman) as the previous step
2. Check your local ip - on linux and macos - ifconfig, windows - ipconfig
3. Edit [issuer.env](compose/env/issuer.env)
   - Change `AGENT_PEER_URL` to use your local ip - `http://your-local-ip:8001` - EXAMPLE `http://192.168.111.53:8001`
   - Change `AGENT_NAME` and `AGENT_KEY` - those are the name and the key of the wallet
   - Change `AGENT_DID_SEED` - this is a seed for private key from which the DID will be created.
4. Start the issuer with `yarn run infra:issuer` or `npm run infra:issuer`
5. Connect to the socket via postman. `ws://localhost:8081`
6. `Create new invitation` via postman request, on the socket listener you will receive invitation url response
7. Copy and paste this url in the chat
    

8. Another OCM (which performed the same setup steps, but with different values) should get this invitation url
8. Call `accept invitation` via postman with this invitation url as a body payload
9. Response will be returned on the socket, that a connection is made. 
10. Get the connectionId from this response
11. Send basic message with connectionId and a string message
    

12. On the socket of issuer a event will be received with the message and connection id.

## License
This project is licensed under the AGPL License - see the [LICENSE](LICENSE) file for details.