RUES

The Rusk Universal Event System (RUES) is an integral part of the architecture of Dusk, providing a powerful mechanism for handling real-time communication with an event-driven approach.

RUES is designed to handle binary proofs, binary streams, and on-demand event-driven data, making it ideal for applications that need to process binary proofs or continuous binary data streams. It also enables on-demand data dispatching and real-time notifications, supporting applications like wallet operations that require high-performance binary data handling. This is achieved by avoiding the need to convert data to JSON or base64.

Session Management

Before interacting with RUES, clients must establish a WebSocket session with a Rusk node. This session forms the backbone of real-time event streaming between the client and the node.

Session Initialization

To start a session, initiate a WebSocket connection to the node. Upon connection, the server responds with a Rusk-Session-Id, a 16 byte random nonce that is essential for event subscriptions and dispatches.

wss://[node-address]/on

Session Persistence

Ensure that your WebSocket connection remains open for as long as you require real-time event streaming. In a load-balanced environment, consistent routing is required to maintain session persistence.

Session Termination

Sessions can be terminated by either the client or the server. When the WebSocket connection is closed, all event subscriptions are automatically canceled.

Event Identification

Every event in RUES is identified by a unique URL structure, which allows for fine-grained interaction with blockchain components.

Event URL Structure

/on/[target]/[topic]

target: The blockchain component (e.g., contracts, transactions, blocks, node, graphql).
topic: The event type (e.g., accepted, statechange, propagate).

Example URLs:

General Event: /on/contracts/deploy
Specific Event: /on/contracts:contract_id/[topic]

In more granular cases, the target can represent specific elements within components. For example:

/on/transactions:transaction_id/included
/on/blocks:block_hash/accepted

Event Subscriptions

RUES enables clients to subscribe to specific events on a node. Subscriptions use the HTTP GET method and require the Rusk-Session-Id for authentication.

Request

GET https://[node-address]/on/[target]/[topic]

Example

GET https://nodes.dusk.network/on/contracts:efda355bc94a3be09006dc90f3714a0ee22c586c5e577e429ef3b5e3e464a8da/item-added

Headers

Name	Description
`Rusk-Version`	Specifies the compatible Rusk version
`Rusk-Session-Id`	Identifies the current session

Response Codes

Status code	When
`200 OK`	Successful subscription
`400 Bad Request`	`Rusk-Version` incompatibility
`424 Failed Dependency`	`Rusk-Session-Id` issues
`404 Not Found`	`[component]` or `[target]` not found

Unsubscribe

To unsubscribe from an event, use the HTTP DELETE method.

Request

DELETE https://[node-address]/on/[target]/[topic]

Example

DELETE https://nodes.dusk.network/on/contracts:efda355bc94a3be09006dc90f3714a0ee22c586c5e577e429ef3b5e3e464a8da/item-removed

Headers

Name	Description
`Rusk-Version`	Specifies the compatible Rusk version
`Rusk-Session-Id`	Identifies the current session

Response Codes

Status code	When
`200 OK`	Successful unsubscription
`400 Bad Request`	`Rusk-Version` incompatibility
`424 Failed Dependency`	`Rusk-Session-Id` issues
`404 Not Found`	`[component]`, `[target]` or `[topic]` not found

Event Dispatch

Dispatching events allows clients to send specific data to the node and request data. The POST method is used for this purpose, often including a request body with the event payload.

Dispatch

Request

POST https://[node-address]/on/[target]/[topic]

Example

POST https://nodes.dusk.network/on/contracts:efda355bc94a3be09006dc90f3714a0ee22c586c5e577e429ef3b5e3e464a8da/sync

Headers

Name	Description
`Rusk-Version`	Specifies the compatible Rusk version
`Rusk-Session-Id`	Identifies the current session
`Content-Type`	Usually `application/json` or `application/octet-stream`
`Content-Length`	The length of the message body in octets (8-bit bytes)
`Accept`	Media type(s) that is/are acceptable for a response message

Response Codes

Status code	When
`200 OK`	Event received succesfully, response generated
`202 Accepted`	Event accepted for processing
`400 Bad Request`	`Rusk-Version` mismatch
`424 Failed Dependency`	`Rusk-Session-Id` mismatch
`404 Not Found`	`[component]`, `[target]`, or `[topic]` not found
`422 Unprocessable Content`	Payload cannot be processed with the given `Content-Type`

General Endpoints

These are endpoints accessible regardless of the node role. They include queries for general blockchain state and node information.

GraphQL Queries

Endpoint: /on/graphql/query

Enables GraphQL-style queries against the Dusk blockchain.

Method: POST

Example Request:

POST https://nodes.dusk.network/on/graphql/query

Request Body:

Example query for requesting the latest block.

query { block(height: -1) { header { height } } }

Example Response:

{
    "block": {
        "header": {
            "height": 20241015
        }
    }
}

Node

Node Info

Endpoint: /on/node/info

Retrieves general information about the node, like the chain ID of the network the node operates on, its bootstrapping nodes, the Rusk version it uses and its Kadcast IP address.

Method: POST

Example Request:

POST https://nodes.dusk.network/on/node/info

Example Response:

{
    "bootstrapping_nodes": [
        "173.212.198.91:9000",
        "188.34.201.78:9000",
        "94.72.105.11:9000",
        "64.44.41.61:9000",
        "158.220.83.234:9000"
    ],
    "chain_id": 48,
    "kadcast_address": "127.0.0.1:9000",
    "version": "0.8.0",
    "version_build": "0.8.0 (027b9787 2024-09-14)"
}

Provisioners

Endpoint: /on/node/provisioners

Fetches the list of provisioners (validators).

Method: POST

Example Request:

POST https://nodes.dusk.network/on/node/provisioners

Example Response:

[
    {
        "amount": 0,
        "eligibility": 0,
        "key": "mvft6AXjR1mDtg1Qo3GzGBKZAvvxY1S6h41DSEPh9Ewj9GFR61rPQnjVaM1W9nqkHijRC2d5Yo4FSBwU8wf9eHeEJYXuMSrB7eJxvsY6HjCeDJ9pKfJLdjayAfrxEyudvx2",
        "reward": 943226500000
    },
    {
        "amount": 1000000000000,
        "eligibility": 0,
        "key": "oCqYsUMRqpRn2kSabH52Gt6FQCwH5JXj5MtRdYVtjMSJ73AFvdbPf98p3gz98fQwNy9ZBiDem6m9BivzURKFSKLYWP3N9JahSPZs9PnZ996P18rTGAjQTNFsxtbrKx79yWu",
        "reward": 8485066974496
    }
]

Common Reference String (CRS)

Endpoint: /on/node/crs

Retrieves the CRS used by the network.

Method: POST

Example Request:

POST https://nodes.dusk.network/on/node/crs

Example Response:

a9909cd1...580a0000

Blocks

Block Events

Endpoint: /on/blocks:[block-hash]/[topic], where [topic] is optional. Block events can have the topic accepted, or statechange.

accepted: Indicates that a block has been accepted into the chain.
statechange: Represents a change in the state of a block. The state of a block can be either finalized or confirmed.

Method: GET

Example Request:

This example request listens to the accepted topic for a given block.

GET https://nodes.dusk.network/on/blocks/accepted

Example Event:

The event is returned as raw binary data. Ensure that your client can properly handle these formats according to the RUES specifications. Example for a newly accepted block.

00000000: 6B 00 00 00 7B 22 43 6F 6E 74 65 6E 74 2D 4C 6F    k...{"Content-Lo
00000010: 63 61 74 69 6F 6E 22 3A 22 2F 6F 6E 2F 62 6C 6F    cation":"/on/blo
00000020: 63 6B 73 3A 37 34 31 61 66 62 62 36 37 61 31 61    cks:741afbb67a1a
...
00000540: 30 30 30 30 30 30 30 30 30 30 30 22 2C 22 76 65    00000000000","ve
00000550: 72 73 69 6F 6E 22 3A 31 7D 2C 22 74 72 61 6E 73    rsion":1},"trans
00000560: 61 63 74 69 6F 6E 73 22 3A 5B 5D 7D                actions":[]}

Gas Price

This endpoint retrieves the gas price for the latest blocks.

Endpoint: /on/blocks/gas-price

Method: POST

Example Request:

POST https://nodes.dusk.network/on/blocks/gas-price

Example Response:

{
    "average": 1,
    "max": 1,
    "median": 1,
    "min":1
}

Transactions

Transaction Events

Endpoint: /on/transactions/[topic], where [topic] is mandatory. Transaction events can have the topic Removed, Included, or Executed.

Removed: Indicates that the transaction has been removed from the mempool.
Included: A transaction has been included in the mempool.
Executed: A transaction that has been executed in an accepted block.

Method: GET

Example Request:

This example request listens to the Executed topic for any incoming transaction.

GET https://nodes.dusk.network/on/transactions/Executed

Example Event:

The event is returned as raw binary data. Ensure that your client can properly handle these formats according to the RUES specifications. Example for an executed Moonlight transaction.

00000000: 71 00 00 00 7B 22 43 6F 6E 74 65 6E 74 2D 4C 6F    q...{"Content-Lo
00000010: 63 61 74 69 6F 6E 22 3A 22 2F 6F 6E 2F 74 72 61    cation":"/on/tra
00000020: 6E 73 61 63 74 69 6F 6E 73 3A 37 63 34 33 36 35    nsactions:7c4365
...
00000230: 79 70 65 22 3A 22 6D 6F 6F 6E 6C 69 67 68 74 22    ype":"moonlight"
00000240: 2C 22 76 61 6C 75 65 22 3A 31 30 30 30 30 30 30    ,"value":1000000
00000250: 30 30 30 7D 7D                                     000}}

Preverify

This endpoint pre-verifies a transaction without executing or propagating it. The transaction is checked to ensure it conforms to network rules before being propagated or executed.

Endpoint: /on/transactions/preverify

Method: POST

Example Request:

POST https://nodes.dusk.network/on/transactions/preverify

Request Body:

The request body should contain the raw binary representation of a transaction.

a9909cd1...580a0000

Example Response:

Upon success, the transaction will be pre-verified, but no specific data is returned unless there is an error.

Propagate

This endpoint propagates a transaction across the network.

Endpoint: /on/transactions/propagate

Method: POST

Example Request:

POST https://nodes.dusk.network/on/transactions/propagate

Request Body:

The request body should contain the raw binary representation of a transaction.

a9909cd1...580a0000

Example Response:

Upon success, the transaction will be propagated across the network. This endpoint returns a response indicating success but no specific data.

Contracts

Contract Events

Endpoint: /on/contracts:[contract-id]/[event-name], where [event-name] is optional. If the event name is not provided, the connection will listen to all events on the given contract.

Method: GET

Example Request:

This example request listens to stake events from the stake contract.

GET https://nodes.dusk.network/on/contracts:0200000000000000000000000000000000000000000000000000000000000000/stake

Example Event:

The event is returned as raw binary data. Ensure that your client can properly handle these formats according to the RUES specifications. Example for a stake event.

00000000: BC 00 00 00 7B 22 43 6F 6E 74 65 6E 74 2D 4C 6F    ....{"Content-Lo
00000010: 63 61 74 69 6F 6E 22 3A 22 2F 6F 6E 2F 63 6F 6E    cation":"/on/con
00000020: 74 72 61 63 74 73 3A 30 32 30 30 30 30 30 30 30    tracts:020000000
...
00000230: 34 B3 5B F3 E4 06 C9 C4 33 34 62 A3 38 6F A2 D5    4.[.....34b.8o..
00000240: 47 CC 52 71 A9 0F 1D 18 00 00 00 00 00 00 00 00    G.Rq............
00000250: 00 10 A5 D4 E8 00 00 00                            ........

Network

Peers

This endpoint retrieves a list of peers connected to the node, where the given value is the amount of peers to return, if available.

Endpoint: /on/network/peers

Method: GET

Example Request:

POST https://nodes.dusk.network/on/network/peers

Request Body:

Example Response:

[
    "173.212.198.91:9000",
    "188.34.201.78:9000",
    "94.72.105.11:9000",
    "64.44.41.61:9000",
    "158.220.83.234:9000"
]

Archive node Endpoints

These endpoints provide access to historical data and events stored by archive nodes.

Moonlight Transaction History

This endpoint provides access to the Moonlight transaction history stored by archive nodes in an efficient way.

Details to be filled in based on implementation.

Historical Events

This endpoint provides access to other historical events in the blockchain.

Details to be filled in based on implementation.

Prover Endpoints

The Provers in the network are responsible for generating Zero-Knowledge proofs. These endpoints offer proof-related functionality.

Prove

This endpoint triggers the prover to generate a Zero-Knowledge proof for the provided data.

Endpoint: /on/prover/prove

Method: POST

Example Request:

POST https://nodes.dusk.network/on/prover/prove

Request Body:

The request body should contain raw binary data

a9909cd1...580a0000

Example Response:

Upon success, the prover will return the generated proof, likely as raw binary data.

a9909cd1...580a0000

RUES

Session Management

Session Initialization

Session Persistence

Session Termination

Event Identification

Event URL Structure

Event Subscriptions

Subscribe

Request

Example

Headers

Response Codes

Unsubscribe

Request

Example

Headers

Response Codes

Event Dispatch

Dispatch

Request

Example

Headers

Response Codes

General Endpoints

GraphQL Queries

Node

Node Info

Provisioners

Common Reference String (CRS)

Blocks

Block Events

Gas Price

Transactions

Transaction Events

Preverify

Propagate

Contracts

Contract Events

Network

Peers

Archive node Endpoints

Moonlight Transaction History

Historical Events

Prover Endpoints

Prove