RPC and Subscriptions

Typed RPC methods, transport choices, websocket subscriptions, and production guidance.

solana_kit_rpc and solana_kit_rpc_subscriptions are the backbone of most application-facing Solana I/O.

Use them together when you need both:

request/response flows over JSON-RPC HTTP
realtime notifications over websockets

Typed RPC requests#

Typed RPC methods#

When working with an Rpc, prefer typed convenience helpers over stringly method calls:

import 'package:solana_kit/solana_kit.dart';

final rpc = createSolanaRpc(url: 'https://api.mainnet-beta.solana.com');
final slot = await rpc.getSlot().send();
final blockHeight = await rpc.getBlockHeight().send();

These helpers forward to canonical params builders in solana_kit_rpc_api and return lazy PendingRpcRequest<T> values.

Why typed RPC matters#

Typed RPC methods give you:

discoverable method names in IDE autocomplete
compile-time parameter shapes
fewer raw Map<String, Object?> escape hatches in application code
reusable request logic across services and tests

Subscription clients#

Use websocket subscriptions for account changes, signature updates, program logs, and slot notifications.

Packages involved:

solana_kit_rpc_subscriptions — high-level orchestration
solana_kit_rpc_subscriptions_api — typed subscription method builders
solana_kit_rpc_subscriptions_channel_websocket — websocket transport/channel implementation
solana_kit_subscribable — stream-friendly subscription primitives

Typical split of responsibilities#

use rpc for reads, writes, and transaction submission
use rpcSubscriptions for realtime updates
keep transport setup at your app boundary so you can tune timeouts, headers, or connection reuse centrally

Large payload handling#

Optional Isolate JSON Decoding#

For large Solana RPC payloads, you can offload BigInt-aware JSON parsing to a background isolate.

import 'package:solana_kit_rpc_transport_http/solana_kit_rpc_transport_http.dart';

final transport = createHttpTransportForSolanaRpc(
  url: 'https://api.mainnet-beta.solana.com',
  decodeSolanaJsonInIsolate: true,
  solanaJsonIsolateThreshold: 262144,
);

For direct parsing, use parseJsonWithBigIntsAsync(...) with runInIsolate: true.