*__name__*: Rpc *__summary__*: The API may use a HTTP or WebSockets provider. *__description__*: It allows for querying a Polkadot Client Node. WebSockets provider is recommended since HTTP provider only supports basic querying. ```mermaid graph LR; A[Api] --> |WebSockets| B[WsProvider]; B --> |endpoint| C[ws://127.0.0.1:9944] ``` *__example__*: ```javascript import Api from '@polkadot/rpc-core'; import WsProvider from '@polkadot/rpc-provider/ws'; const provider = new WsProvider('ws://127.0.0.1:9944'); const api = new Api(provider); ``` # Hierarchy **Rpc** # Implements * `RpcInterface` # Constructors ## constructor ⊕ **new Rpc**(provider?: *`ProviderInterface`*): [Rpc](_index_.rpc.md) *Defined in [index.ts:43](https://github.com/polkadot-js/api/blob/b09cbf6/packages/rpc-core/src/index.ts#L43)* *__constructor__*: Default constructor for the Api Object **Parameters:** | Param | Type | Default value | Description | | ------ | ------ | ------ | ------ | | `Default value` provider | `ProviderInterface` | new WsProvider() | An API provider using HTTP or WebSocket | **Returns:** [Rpc](_index_.rpc.md) ___ # Properties ## _provider **● _provider**: *`ProviderInterface`* *Defined in [index.ts:39](https://github.com/polkadot-js/api/blob/b09cbf6/packages/rpc-core/src/index.ts#L39)* ___ ## author **● author**: *`RpcInterface$Section`* *Defined in [index.ts:40](https://github.com/polkadot-js/api/blob/b09cbf6/packages/rpc-core/src/index.ts#L40)* ___ ## chain **● chain**: *`RpcInterface$Section`* *Defined in [index.ts:41](https://github.com/polkadot-js/api/blob/b09cbf6/packages/rpc-core/src/index.ts#L41)* ___ ## state **● state**: *`RpcInterface$Section`* *Defined in [index.ts:42](https://github.com/polkadot-js/api/blob/b09cbf6/packages/rpc-core/src/index.ts#L42)* ___ ## system **● system**: *`RpcInterface$Section`* *Defined in [index.ts:43](https://github.com/polkadot-js/api/blob/b09cbf6/packages/rpc-core/src/index.ts#L43)* ___ # Methods ## `` signature ▸ **signature**(__namedParameters: *`object`*): `string` *Defined in [index.ts:76](https://github.com/polkadot-js/api/blob/b09cbf6/packages/rpc-core/src/index.ts#L76)* *__name__*: signature *__summary__*: Returns a string representation of the method with inputs and outputs. *__description__*: Formats the name, inputs and outputs into a human-readable string. This contains the input parameter names input types and output type. *__example__*: ```javascript import Api from '@polkadot/rpc-core'; Api.signature({ name: 'test_method', params: [ { name: 'dest', type: 'Address' } ], type: 'Address' }); // => test_method (dest: Address): Address ``` **Parameters:** | Param | Type | | ------ | ------ | | __namedParameters | `object` | **Returns:** `string` ___