Through the use of JSON-RPC, Nimiq nodes expose a set of standardized methods and endpoints that allow external applications and tools to interact, stream and control the behavior of the nodes. This includes functionalities such as retrieving information about the blockchain state, submitting transactions, managing accounts, and configuring node settings.
Authentication with the JSON-RPC server occurs via HTTP Basic Authentication. The username and password can be configured within the rpc-server section of the client.toml file. Authentication with the RPC server functions by adding an Authorization header to the HTTP request. The value of this header is provided in the format Basic <credentials> where credentials is a base64-encoded string containing the username and password separated by a colon.
echo -n 'super:secret' | base64
# Output: c3VwZXI6c2VjcmV0
curl --request POST \
--url http://127.0.0.1:8648 \
--header 'Authorization: Basic c3VwZXI6c2VjcmV0' \
--header 'Content-Type: application/json' \
--data '{
"jsonrpc": "2.0",
"method": "getLatestBlock",
"params": [false],
"id": 1
}'The JSON-RPC specification defines two ways of passing parameters to methods: named parameters, providing flexibility by labeling parameters, and positional parameters, relying on their order in the request. At the moment the JSON-RPC server implementation only supports positional parameters, meaning parameter order must match the server's expectation.
{
"jsonrpc": "2.0",
"params": {"hour": 12, "minutes": 30}, // [!code --]
"params": [12, 30], // [!code ++]
}