RPC API

Getting Started

You can access the SASEUL node with HTTP or HTTPS and use RPC in the GET or POST method.

In case of GET method, provide request parameters in query string.

• URL: {host}/{RPC_API_NAME}?{request parameters}

In case of POST method, provide request parameters in form-data with key-value format.

• URL: {host}/{RPC_API_NAME}
• Body: {request parameters}

Basic Operation

Ping

• URL: {host}/ping

Check that the SASEUL node is active.

Return Value

{
    "code": 200,
    "data": []
}

Info

• URL: {host}/info

Get the node’s status, version, mining state, and latest block information.

Return Value

{
  "code": 200,
  "data": {
    "status": "is_running",
    "version": "2.2.0.3",
    "mining": false,
    "last_block": {
      "height": 3410254,
      "s_timestamp": 1773050473000000,
      "previous_blockhash": "064c947b1358...",
      "blockhash": "064c947b9cac...",
      "transaction_count": 1
    },
    "last_resource_block": {
      "height": 2036292,
      "blockhash": "064c9478eb77...",
      "previous_blockhash": "064c94722363...",
      "nonce": "08e5b4126a3f...",
      "timestamp": 1773050427832196,
      "difficulty": "720140924964913",
      "main_height": 3410247,
      "main_blockhash": "064c9471e57d...",
      "validator": "b910526bb3a8...",
      "miner": "bd4f109b6a96...",
      "receipt_count": 0
    }
  }
}

Field	Description
status	Node process status (e.g. is_running).
version	SASEUL version string.
mining	Whether mining is active.
last_block	Latest main chain block.
last_resource_block	Latest resource chain block.

Tracker Operation

Peer

• URL: {host}/peer

Get the list of nodes on the network that are associated with the SASEUL node.

Request Parameters

Parameter	Requirements	Type	Maxlength	Description
register	optional	Boolean(int)		Determines whether to send a request to the target node to register itself.
host	optional	String		If the ‘register’ variable is true, enter the host variable to register.
authentication	optional	Boolean(int)		Requests the network information of the target node.
height	optional	Int		If the ‘authentication’ variable is true, add the verification block number to be registered.

Return value

{
    "code": 200,
    "data": {
        "peers": {
            ...
        },
        "known_hosts": [
            ...
        ],
        "node": {
            ...
        }
    },
    "register": true,
    "registerResult": true,
    "authentication": true
}

Round Operation

Round

• URL: {host}/round

Get information of a specific block height.

Request Parameters

Parameter	Requirements	Type	Maxlength	Description
chain_type	optional	String		main
height	optional	int		height of recent block

Return value

{
    "code": 200,
    "data": {
        "block": {
            ...
        },
    "sync_limit": 40362,
    "timestamp": 1656048496844843
    }
}

Smart Contracts and Requests

Request

• URL: {host}/request

Execute a smart contract read method using data stored in the local node.

Request Parameters

Parameter	Required	Type	Description
request	Yes	String	JSON-encoded method call: {"type":"<method_name>", ...}
public_key	No	String	Public key for signed requests.
signature	No	String	Signature for signed requests.

Example

curl -X POST main.saseul.net/request \
  --data 'request={"type":"GetBalance","address":"<address>"}'

RawRequest

• URL: {host}/rawrequest

Same as request, but accepts a single JSON body instead of form-data parameters.

Request Parameters

Parameter	Required	Type	Description
body	Yes	Object	{"request":{"type":"<method_name>", ...}, "public_key":"...", "signature":"..."}

Example

curl -X POST main.saseul.net/rawrequest \
  -H 'Content-Type: application/json' \
  --data '{"request":{"type":"GetBalance","address":"<address>"}}'

SendTransaction

• URL: {host}/sendtransaction

Execute a smart contract method to create and broadcast a transaction.

Request Parameters

Parameter	Required	Type	Description
transaction	Yes	String	JSON-encoded method call: {"type":"<method_name>", ...}
public_key	Yes	String	Public key of the signer.
signature	Yes	String	Signature of the transaction.

Example

curl -X POST main.saseul.net/sendtransaction \
  --data 'transaction={"type":"Send","to":"<address>","amount":"<amount>"}&public_key=<public_key>&signature=<signature>'

SendRawTransaction

• URL: {host}/sendrawtransaction

Same as sendtransaction, but accepts a single JSON body instead of form-data parameters.

Request Parameters

Parameter	Required	Type	Description
body	Yes	Object	{"transaction":{"type":"<method_name>", ...}, "public_key":"...", "signature":"..."}

Example

curl -X POST main.saseul.net/sendrawtransaction \
  -H 'Content-Type: application/json' \
  --data '{"transaction":{"type":"Send","to":"<address>","amount":"<amount>"},"public_key":"<public_key>","signature":"<signature>"}'

Weight

• URL: {host}/weight

Calculate the fee weight of a transaction before broadcasting. Use this to estimate the transaction cost in advance.

Request Parameters

Same parameters as SendTransaction or SendRawTransaction.

Data Inspection

Inspect

• URL: {host}/inspect

Query contract status data directly by status key. This allows low-level access to on-chain state values.

Request Parameters

Parameter	Required	Type	Description
type	Yes	String	Status type: universal or local.
key	Yes	String	Status key to look up.

Example

curl -X POST main.saseul.net/inspect \
  --data 'type=universal&key=<status_key>'

How to compute a status key

A status key is derived from the contract code. For example, if a contract reads a universal status like this:

let total_supply = op.read_universal('total_supply', SASEUL.Enc.ZERO_ADDRESS, '0');

You can compute the corresponding status key using SASEUL JS:

let zero_address = SASEUL.Enc.ZERO_ADDRESS;
let system_nonce = '<nonce from ini file>';
let space = SASEUL.Enc.hash(system_nonce);
let key = 'total_supply';
let status_key = SASEUL.Enc.hash(zero_address + space + key) + zero_address;

The key format is: hash(writer + space + attr) + id, where writer is the contract deployer address, space is the hashed contract nonce (the nonce value is defined in the contract’s ini file), attr is the status field name, and id is the target address.