Security News
Introducing the Socket Python SDK
The initial version of the Socket Python SDK is now on PyPI, enabling developers to more easily interact with the Socket REST API in Python projects.
@polkadot/api
Advanced tools
The Polkadot-JS API provides easy-to-use wrappers around JSONRPC calls that flow from an application to a node. It handles all the encoding and decoding or parameters, provides access to RPC functions and allows for the query of chain state and the submission of transactions.
The API wrappers provide a standard interface for use -
.create(<optional ApiOptions>)
that returns an API instance when connected, decorated and ready-to use. ApiOptions can include an optional WsProvider and optional custom type definitions { provider: <Optional WsProvider>, types: <Optional RegistryTypes> }
.new Api(<optional ApiOptions>)
, exposing the isReady
getterapi.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.tx.<section>.<method>
provides the ability to create a transaction, like chain state, this list is populated from a runtime query
api.consts.<section>.<constant>
provides access to the module constants (parameter types).
There are two flavours of the API provided, one allowing a standard interface via JavaScript Promises and the second provides an Observable wrapper using RxJS. Depending on your use-case and familiarity, you can choose either (or even both) for your application.
.create(...)
. Additionally any subscription method uses (value) => {}
callbacks, returning the value as the subscription is updated..create(...)
. In the same fashion subscription-based methods return long-running Observables that update with the latest values.Substrate (upon which Polkadot is built) uses on-chain WASM runtimes, allowing for upgradability. Each runtime defining the actual chain extrinsics (submitted transactions and block intrinsics) as well as available entries in the chain state. Due to this, the API endpoints for queries and transactions are dynamically populated from the running chain.
Due to this dynamic nature, this API departs from traditional APIs which only has fixed endpoints, driving use by what is available by the runtime. As a start, this generic nature has a learning curve, although the provided documentation, examples and linked documentation tries to make that experience as seamless as possible.
Installation -
npm install --save @polkadot/api
Subscribing to blocks via Promise-based API -
import { ApiPromise } from '@polkadot/api';
// initialise via static create
const api = await ApiPromise.create();
// make a call to retrieve the current network head
api.rpc.chain.subscribeNewHeads((header) => {
console.log(`Chain is at #${header.number}`);
});
Subscribing to blocks via RxJS-based API -
import { ApiRx } from '@polkadot/api';
// initialise via static create
const api = await ApiRx.create().toPromise();
// make a call to retrieve the current network head
api.rpc.chain.subscribeNewHeads().subscribe((header) => {
console.log(`Chain is at #${header.number}`);
});
Additional types used by runtime modules can be added when a new instance of the API is created. This is necessary if the runtime modules use types which are not available in the base Substrate runtime.
import { ApiPromise } from '@polkadot/api';
// initialise via static create and register custom types
const api = await ApiPromise.create({
types: {
CustomTypesExample: {
"id": "u32",
"data": "Vec<u8>",
"deposit": "Balance",
"owner": "AccountId",
"application_expiry": "Moment",
"whitelisted": "bool",
"challenge_id": "u32"
}
}
});
Some of the users of the API (let us know if you are missing from the list), include -
10.11.2 Dec 18, 2023
Contributed:
chainIsEthereum
key to Registry
interface (Thanks to https://github.com/fgamundi)ChargeAssetTxPayment
(Thanks to https://github.com/bee344)Changes:
[8a;32]
types in known keysFAQs
Promise and RxJS wrappers around the Polkadot JS RPC
The npm package @polkadot/api receives a total of 82,798 weekly downloads. As such, @polkadot/api popularity was classified as popular.
We found that @polkadot/api demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 2 open source maintainers collaborating on the project.
Did you know?
Socket for GitHub automatically highlights issues in each pull request and monitors the health of all your open source dependencies. Discover the contents of your packages and block harmful activity before you install or update your dependencies.
Security News
The initial version of the Socket Python SDK is now on PyPI, enabling developers to more easily interact with the Socket REST API in Python projects.
Security News
Floating dependency ranges in npm can introduce instability and security risks into your project by allowing unverified or incompatible versions to be installed automatically, leading to unpredictable behavior and potential conflicts.
Security News
A new Rust RFC proposes "Trusted Publishing" for Crates.io, introducing short-lived access tokens via OIDC to improve security and reduce risks associated with long-lived API tokens.