Capi is a framework for crafting interactions with Substrate chains
npm install capi> Announcing Capi v0.1.0-gamma.0
Capi is a framework for crafting interactions with Substrate chains. It consists
of a development server and fluent API, which facilitates multichain
interactions without compromising either performance or ease of use.
- Manual →
Guides to get up and running
- Examples →
SHOW ME THE CODE
- API Reference →
A generated API
reference, based on type signatures and TSDocs.
``sh`
npm i capi
> Note: The minimum supported Node version is 20, as we require the
> Web Crypto API
> be accessible from globalThis.crypto for the sake of browser compatibility.
Deno Equivalent
import_map.json
`json`
{
"imports": {
"capi": "https://deno.land/x/capi/mod.ts",
"capi/nets": "https://deno.land/x/capi/nets/mod.ts"
}
}
> Note: For now, we only support the latest 1.x version of Deno.
Create a nets.ts and specify the chains with which you'd like to interact.
`ts
import { bins, net } from "capi/nets"
const bin = bins({ polkadot: ["polkadot", "v0.9.38"] })
// A Polkadot development network
export const polkadotDev = net.dev({
bin: bin.polkadot,
chain: "polkadot-dev",
})
// The Polkadot relay chain
export const polkadot = net.ws({
url: "wss://rpc.polkadot.io/",
targets: { dev: polkadotDev },
})
`
In this documentation, we use Capi's CLI via the alias "capi", instead of via
its full path:
`sh`
./node_modules/.bin/capi
Deno Equivalent
`sh`
deno run -A https://deno.land/x/capi/main.ts
`sh`
capi sync node
Deno Equivalent
`sh`
capi sync deno
Retrieve the first 10 entries from a storage map of Polkadot.
`ts
import { polkadot } from "@capi/polkadot"
const accounts = await polkadot.System.Account.entries({ limit: 10 }).run()
`
During development, we may want to swap out the underlying connection with that
of a devnet. This can be achieved via targets — by specifying alternate targets
in your nets.ts file, you can switch to them by wrapping your command withcapi serve --target someTarget --. For example:
`sh`
capi serve --target dev -- node main.js
> Other examples:
>
> - capi serve --target dev -- npm run start
> -
Within a fresh clone of this repository...
`sh`
deno task sync # only needed once
deno task run examples/
Or, to run an example with Node:
`sh``
deno task sync # only needed once
deno task dnt --examples # only needed once
deno task capi serve -- node target/npm/capi-examples/esm/examples/
In a likely future of specialized, interoperable chains, developers will need to
make use of on-chain programs to satisfy varying use cases; the expertise
required to interact with these on-chain programs is currently greater than that
which _should_ be expected of app developers. Does this mean that app developers
must forgo integrating with this blossoming infrastructure? We think not; **the
open source community can use Capi to abstract over the atomics of the on-chain
world**. An interaction spanning several chains and dozens of methods can be
described with a single Rune[^1].
As you read through this documentation, please consider use cases over which you
might like to abstract; if you wish to add your use case to
Capi's standard library, please
submit an issue.
Everyone interacting in this repo is expected to follow the
code of conduct.
Contributions are welcome and appreciated! Check out the
contributing guide before you dive in.
Capi is Apache licensed.
[^1]: Rune is the unit of composition with which we model Capi programs.