Elixir interfaces to Kujira dApps, for building indexers, APIs and bots
N.B. This is currently a work in progress, as we begin to componentise & open source the infrastructure that powers the Kujira dApps
Add kujira to your list of dependencies in mix.exs:
def deps do
[
{:kujira, "~> 0.1.31"}
]
endCreate a MyApp.Node module, configure the application's pubsub and CometBFT subscriptions
defmodule MyApp.Node do
use Kujira.Node,
otp_app: :my_app,
pubsub: MyApp.PubSub,
subscriptions: ["tm.event='NewBlock'"]
endConfigure the Node connection config/*
config :my_app, MyApp.Node,
host: "127.0.0.1",
port: 9090,
websocket: "wss://rpc-kujira.starsquid.io"Add the Node process to your application.ex
@impl true
def start(_type, _args) do
children = [
#...
MyApp.Node
]
# ...
enddefmodule MyAppWeb.PageController do
alias Cosmos.Base.Tendermint
use MyAppWeb, :controller
import Tendermint.V1beta1.Service.Stub
def index(conn, _params) do
{:ok, %{block: block}} =
get_latest_block(
MyApp.Node.channel(),
Tendermint.V1beta1.GetLatestBlockRequest.new()
)
conn |> assign(:block, block) |> render("index.html")
end
endCometBFT Events can be subscribed to for realtime applications
defmodule MyAppWeb.PageLive do
use MyAppWeb, :live_view
alias Cosmos.Base.Tendermint
import Tendermint.V1beta1.Service.Stub
alias Tendermint.V1beta1.GetLatestBlockRequest, as: LatestBlock
alias Tendermint.V1beta1.GetBlockByHeightRequest, as: Block
def mount(_params, _session, socket) do
MyApp.Node.subscribe("tendermint/event/NewBlock")
{:ok, %{block: block}} = get_latest_block(MyApp.Node.channel(), LatestBlock.new())
{:ok, assign(socket, :block, block)}
end
def handle_info(%{block: %{header: %{height: height}}}, socket) do
{:ok, %{block: block}} =
get_block_by_height(
MyApp.Node.channel(),
Block.new(height: String.to_integer(height))
)
{:noreply, assign(socket, :block, block)}
end
endDocs can be found at https://hexdocs.pm/kujira.