@cennznet/api

CENNZNet Api

The CENNZNet JavaScript SDK for browsers, RN and Node.js.

Install

@cennznet/crml-* are peer dependencies to @cennznet/api, they need to be installed together.

$> npm i --save @cennznet/api @cennznet/crml-generic-asset @cennznet/crml-cennzx-spot @cennznet/crml-attestation

Do not put @plugnet/* or @polkadot/* in your package.json

Usage

Register an endpoint for your project

https://unfrastructure.io/

Connect to Rimu TestNet

<Static> create(options?: ApiOptions | ProviderInterface)

//initialize Api and connect to dev network
const {Api} = require('@cennznet/api')
api = await Api.create({
    provider: 'wss://rimu.unfrastructure.io/ws?apikey=***'
});
// For Rxjs
const {ApiRx} = require('@cennznet/api')
api = await ApiRx.create({
    provider: 'wss://rimu.unfrastructure.io/ws?apikey=***'
}).toPromise();

if provider is a string url, sdk will chose Provider Class based on url protocol. Or you can initialize the provider Instance yourself.

const {WsProvicer, HttpProvider} = require('@cennznet/api');

Use SingleSource Extension as Signer

api.setSigner(window.SingleSource.signer);

Use @cennznet/wallet as Signer

npm i --save @cennznet/wallet

const {SimpleKeyring, Wallet} = require('@cennznet/wallet')

wallet = new Wallet();
await wallet.createNewVault('a passphrase');

api.setSigner(wallet);

Wallet Docs

CennznetExtrinsic

All api.tx.<section>.<method>(...) return CennznetExtrinsic, which have

• addFeeExchangeOpt(feeExchangeOpt: FeeExchangeValue): CennznetExtrinsic so transaction fee will be paid in specified Asset instead of CentraPay
• addDoughnut(doughnut: DoughnutValue): CennznetExtrinsic to embed an permission proof
• fee(sender: AnyAddress): Promise<AssetOf> (or Observable<AssetOf> for ApiRx): estimate the transaction fee this extrinsic will cost

see more

Dynamic vs CRML SDK

CRML stand for CENNZNet Runtime Module

After connecting to CENNZNet, api will dynamically create queries and transaction methods.

• api.rpc.<section>.<method> provides access to actual RPC calls, be it for queries, submission or retrieving chain information
• api.query.<section>.<method> provides access to chain state queries. These are dynamically populated based on what the runtime provides
• api.derive.<section>.<method> provides access to build-in complex state queries which are combination of several basic state queries.
• api.tx.<section>.<method> provides the ability to create a transaction, like chain state, this list is populated from a runtime query

With CRML sdks installed, they will inject themselves in api. api.genericAsset, api.cennzxSpot and api.attestation. Queries, derive queries and tx methods are provided in under these namespaces.

	Dynamic	CRML
Up-To-Date	Always	require upgrade manually
IDE Hints	None, need to check docs/metadata	accurate typescript type definition
Addition Validations	None, e.g: transfer might fail if no enough balance. pay tx fee anyway.	Yes. will stop sending tx, e.g: no enough balance

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More Api Examples