Smart Contract Endpoints

Get Contract

Returns metadata about a specific smart contract deployed on a given blockchain. This is typically used to inspect the contract address, deployment information, version, and VM/runtime details.

Request

GET /blockchains/{blockchainId}/contracts/{address}

For a node running on https://tn-w-1.uledger.net/, the full URL is:
https://tn-w-1.uledger.net//blockchains/{blockchainId}/contracts/{address}

Path parameters

• blockchainId – The blockchain identifier (one of the values returned by GET /blockchains).
• address – The on-chain contract address to inspect.

Response

The response contains contract metadata. Exact fields depend on the node and VM configuration, but commonly include:

• blockchainId – ID of the blockchain where the contract is deployed.
• address – Contract address.
• creator – Address that deployed the contract (if tracked).
• deploymentTxId – Transaction ID that created the contract.
• codeHash – Hash of the contract code or artifact.
• vmType – Contract VM/runtime type.
• version – Contract version, if versioning is enabled.
• status – Current contract status (e.g. ACTIVE, PAUSED, UPGRADED).
• metadata – Optional additional metadata defined by your deployment.

Example response

{

"blockchainId": "{blockchainId}",
"address": "{contractAddress}",
"creator": "{creatorAddress}",
"deploymentTxId": "{deploymentTransactionId}",
"codeHash": "c5b21c4e8f6c4d7e8f3d...",
"vmType": "uledgervm-v1",
"version": 3,
"status": "ACTIVE",
"metadata": {
"name": "ExampleContract",
"description": "Demo contract used for documentation",
"tags": ["demo", "test"]
}
}

cURL

curl -X GET -L "https://tn-w-1.uledger.net//blockchains/{blockchainId}/contracts/{address}" | jq

// Using native fetch (Node 18+)

const blockchainId = "{blockchainId}";
const address = "{contractAddress}";

const res = await fetch(
`https://tn-w-1.uledger.net//blockchains/${blockchainId}/contracts/${address}`
);

if (!res.ok) {
throw new Error(`Request failed with status ${res.status}`);
}

const contract = await res.json();

console.log("Contract address:", contract.address);
console.log("Status:", contract.status);
console.log("VM type:", contract.vmType);

import requests

blockchain_id = "{blockchainId}"
address = "{contractAddress}"

resp = requests.get(
f"https://tn-w-1.uledger.net//blockchains/{blockchain_id}/contracts/{address}"
)
resp.raise_for_status()

contract = resp.json()

print("Contract address:", contract["address"])
print("Status:", contract["status"])
print("VM type:", contract["vmType"])

Get Contract State

Returns the current state snapshot of a smart contract on a given blockchain. The structure of the state is contract-defined and typically exposed as a JSON object or key–value map.

Request

GET /blockchains/{blockchainId}/contracts/{address}/state

For a node running on http://my.node1.uledger.io, the full URL is:
http://my.node1.uledger.io/blockchains/{blockchainId}/contracts/{address}/state

Path parameters

• blockchainId – The blockchain identifier.
• address – The contract address whose state you want to inspect.

Response

The response contains the latest on-chain state for the contract. The exact shape is determined by the contract, but a typical pattern is:

• blockchainId – ID of the chain where the contract lives.
• address – Contract address.
• version – Current contract state/version number.
• state – JSON object representing the contract's state.

Example response

{

"blockchainId": "{blockchainId}",
"address": "{contractAddress}",
"version": 3,
"state": {
"owner": "{ownerAddress}",
"totalSupply": "1000000",
"balances": {
"{ownerAddress}": "750000",
"{otherAddress}": "250000"
},
"paused": false
}
}

cURL

curl -X GET -L "http://my.node1.uledger.io/blockchains/{blockchainId}/contracts/{address}/state" | jq

Node.js

// Using native fetch (Node 18+)

const blockchainId = "{blockchainId}";
const address = "{contractAddress}";

const res = await fetch(
`http://my.node1.uledger.io/blockchains/${blockchainId}/contracts/${address}/state`
);

if (!res.ok) {
throw new Error(`Request failed with status ${res.status}`);
}

const snapshot = await res.json();

console.log("State version:", snapshot.version);
console.log("Contract owner:", snapshot.state.owner);

Python

import requests

blockchain_id = "{blockchainId}"
address = "{contractAddress}"

resp = requests.get(
f"http://my.node1.uledger.io/blockchains/{blockchain_id}/contracts/{address}/state"
)
resp.raise_for_status()

snapshot = resp.json()

print("State version:", snapshot["version"])
print("Contract owner:", snapshot["state"]["owner"])

Get Contract Trace / Logs

Returns the execution trace or logs for a specific contract call, identified by the transaction that invoked the contract. This is useful for debugging and observing emitted events.

Request

GET /blockchains/{blockchainId}/contracts/{address}/trace/{transactionId}

For a node running on http://my.node1.uledger.io, the full URL is:
http://my.node1.uledger.io/blockchains/{blockchainId}/contracts/{address}/trace/{transactionId}

Path parameters

• blockchainId – The blockchain identifier.
• address – Contract address that handled the transaction.
• transactionId – The transaction whose contract execution trace you want.

Response

The response format depends on your node configuration, but a typical structure is:

• blockchainId, address, transactionId – Context of the trace.
• events – Array of contract events/log entries emitted during execution.
• trace – Optional low-level execution trace information.

Example response

{

"blockchainId": "{blockchainId}",
"address": "{contractAddress}",
"transactionId": "{transactionId}",
"events": [
{
"name": "Transfer",
"timestamp": "2025-11-11T20:25:01Z",
"indexedArgs": {
"from": "{fromAddress}",
"to": "{toAddress}"
},
"data": {
"amount": "1000"
}
},
{
"name": "BalanceUpdated",
"timestamp": "2025-11-11T20:25:01Z",
"data": {
"owner": "{toAddress}",
"newBalance": "26000"
}
}
],
"trace": {
"steps": 42,
"gasUsed": 12345
}
}

cURL

curl -X GET -L "http://my.node1.uledger.io/blockchains/{blockchainId}/contracts/{address}/trace/{transactionId}" | jq

Node.js

// Using native fetch (Node 18+)

const blockchainId = "{blockchainId}";
const address = "{contractAddress}";
const transactionId = "{transactionId}";

const res = await fetch(
`http://my.node1.uledger.io/blockchains/${blockchainId}/contracts/${address}/trace/${transactionId}`
);

if (!res.ok) {
throw new Error(`Request failed with status ${res.status}`);
}

const trace = await res.json();

console.log("Events:", trace.events.length);
console.log("First event name:", trace.events[0]?.name);

Python

import requests

blockchain_id = "{blockchainId}"
address = "{contractAddress}"
transaction_id = "{transactionId}"

resp = requests.get(
f"http://my.node1.uledger.io/blockchains/{blockchain_id}/contracts/{address}/trace/{transaction_id}"
)
resp.raise_for_status()

trace = resp.json()

print("Events:", len(trace["events"]))
if trace["events"]:
print("First event name:", trace["events"][0]["name"])