feat: socket reconnect (#2073)

* feat: socket reconnect

Co-Authored-By: Sk Sohab <SKSHOAIBPERSONAL@GMAIL.COM>

* docs

---------

Co-authored-by: Sk Sohab <SKSHOAIBPERSONAL@GMAIL.COM>

.changeset/good-coins-smoke.md

@@ -0,0 +1,5 @@
+---
+"viem": patch
+---
+
+Added reconnect functionality to `webSocket` & `ipc` transports.

site/pages/docs/clients/transports/ipc.md

@@ -65,6 +65,55 @@ const transport = ipc('/tmp/reth.ipc', {
 })
 ```
 
+### reconnect (optional)
+
+- **Type:** `boolean | { maxAttempts?: number, delay?: number }`
+- **Default:** `true`
+
+Whether or not to attempt to reconnect on socket failure.
+
+```ts twoslash
+import { ipc } from 'viem/node'
+// ---cut---
+const transport = ipc('/tmp/reth.ipc', {
+  reconnect: false, // [!code focus]
+})
+```
+
+#### reconnect.attempts (optional)
+
+- **Type:** `number`
+- **Default:** `5`
+
+The max number of times to attempt to reconnect.
+
+```ts twoslash
+import { ipc } from 'viem/node'
+// ---cut---
+const transport = ipc('/tmp/reth.ipc', {
+  reconnect: {
+    attempts: 10, // [!code focus]
+  }
+})
+```
+
+#### reconnect.delay (optional)
+
+- **Type:** `number`
+- **Default:** `2_000`
+
+Retry delay (in ms) between reconnect attempts.
+
+```ts twoslash
+import { ipc } from 'viem/node'
+// ---cut---
+const transport = ipc('/tmp/reth.ipc', {
+  reconnect: {
+    delay: 1_000, // [!code focus]
+  }
+})
+```
+
 ### retryCount (optional)
 
 - **Type:** `number`

site/pages/docs/clients/transports/websocket.md

@@ -68,6 +68,55 @@ const transport = webSocket('wss://eth-mainnet.g.alchemy.com/v2/...', {
 })
 ```
 
+### reconnect (optional)
+
+- **Type:** `boolean | { maxAttempts?: number, delay?: number }`
+- **Default:** `true`
+
+Whether or not to attempt to reconnect on socket failure.
+
+```ts twoslash
+import { webSocket } from 'viem'
+// ---cut---
+const transport = webSocket('wss://eth-mainnet.g.alchemy.com/v2/...', {
+  reconnect: false, // [!code focus]
+})
+```
+
+#### reconnect.attempts (optional)
+
+- **Type:** `number`
+- **Default:** `5`
+
+The max number of times to attempt to reconnect.
+
+```ts twoslash
+import { webSocket } from 'viem'
+// ---cut---
+const transport = webSocket('wss://eth-mainnet.g.alchemy.com/v2/...', {
+  reconnect: {
+    attempts: 10, // [!code focus]
+  }
+})
+```
+
+#### reconnect.delay (optional)
+
+- **Type:** `number`
+- **Default:** `2_000`
+
+Retry delay (in ms) between reconnect attempts.
+
+```ts twoslash
+import { webSocket } from 'viem'
+// ---cut---
+const transport = webSocket('wss://eth-mainnet.g.alchemy.com/v2/...', {
+  reconnect: {
+    delay: 1_000, // [!code focus]
+  }
+})
+```
+
 ### retryCount (optional)
 
 - **Type:** `number`

src/clients/transports/ipc.ts

@@ -3,7 +3,11 @@ import { type UrlRequiredErrorType } from '../../errors/transport.js'
 import type { ErrorType } from '../../errors/utils.js'
 import type { Hash } from '../../types/misc.js'
 import type { RpcResponse } from '../../types/rpc.js'
-import { type IpcRpcClient, getIpcRpcClient } from '../../utils/rpc/ipc.js'
+import {
+  type GetIpcRpcClientOptions,
+  type IpcRpcClient,
+  getIpcRpcClient,
+} from '../../utils/rpc/ipc.js'
 import {
   type CreateTransportErrorType,
   type Transport,
@@ -38,6 +42,11 @@ export type IpcTransportConfig = {
   key?: TransportConfig['key'] | undefined
   /** The name of the Ipc transport. */
   name?: TransportConfig['name'] | undefined
+  /**
+   * Whether or not to attempt to reconnect on socket failure.
+   * @default true
+   */
+  reconnect?: GetIpcRpcClientOptions['reconnect'] | undefined
   /** The max number of times to retry. */
   retryCount?: TransportConfig['retryCount'] | undefined
   /** The base delay (in ms) between retries. */
@@ -66,7 +75,7 @@ export function ipc(
   path: string,
   config: IpcTransportConfig = {},
 ): IpcTransport {
-  const { key = 'ipc', name = 'IPC JSON-RPC', retryDelay } = config
+  const { key = 'ipc', name = 'IPC JSON-RPC', reconnect, retryDelay } = config
   return ({ retryCount: retryCount_, timeout: timeout_ }) => {
     const retryCount = config.retryCount ?? retryCount_
     const timeout = timeout_ ?? config.timeout ?? 10_000
@@ -76,7 +85,7 @@ export function ipc(
         name,
         async request({ method, params }) {
           const body = { method, params }
-          const rpcClient = await getIpcRpcClient(path)
+          const rpcClient = await getIpcRpcClient(path, { reconnect })
           const { error, result } = await rpcClient.requestAsync({
             body,
             timeout,

src/clients/transports/webSocket.ts

@@ -8,7 +8,10 @@ import type { Hash } from '../../types/misc.js'
 import type { RpcResponse } from '../../types/rpc.js'
 import { getSocket } from '../../utils/rpc/compat.js'
 import type { SocketRpcClient } from '../../utils/rpc/socket.js'
-import { getWebSocketRpcClient } from '../../utils/rpc/webSocket.js'
+import {
+  type GetWebSocketRpcClientOptions,
+  getWebSocketRpcClient,
+} from '../../utils/rpc/webSocket.js'
 import {
   type CreateTransportErrorType,
   type Transport,
@@ -43,6 +46,11 @@ export type WebSocketTransportConfig = {
   key?: TransportConfig['key'] | undefined
   /** The name of the WebSocket transport. */
   name?: TransportConfig['name'] | undefined
+  /**
+   * Whether or not to attempt to reconnect on socket failure.
+   * @default true
+   */
+  reconnect?: GetWebSocketRpcClientOptions['reconnect'] | undefined
   /** The max number of times to retry. */
   retryCount?: TransportConfig['retryCount'] | undefined
   /** The base delay (in ms) between retries. */
@@ -76,7 +84,12 @@ export function webSocket(
   url?: string,
   config: WebSocketTransportConfig = {},
 ): WebSocketTransport {
-  const { key = 'webSocket', name = 'WebSocket JSON-RPC', retryDelay } = config
+  const {
+    key = 'webSocket',
+    name = 'WebSocket JSON-RPC',
+    reconnect,
+    retryDelay,
+  } = config
   return ({ chain, retryCount: retryCount_, timeout: timeout_ }) => {
     const retryCount = config.retryCount ?? retryCount_
     const timeout = timeout_ ?? config.timeout ?? 10_000
@@ -88,7 +101,7 @@ export function webSocket(
         name,
         async request({ method, params }) {
           const body = { method, params }
-          const rpcClient = await getWebSocketRpcClient(url_)
+          const rpcClient = await getWebSocketRpcClient(url_, { reconnect })
           const { error, result } = await rpcClient.requestAsync({
             body,
             timeout,

src/utils/rpc/ipc.ts

@@ -1,11 +1,17 @@
 import { type Socket as NetSocket, connect } from 'node:net'
 import { WebSocketRequestError } from '../../index.js'
 import {
+  type GetSocketRpcClientParameters,
   type Socket,
   type SocketRpcClient,
   getSocketRpcClient,
 } from './socket.js'
 
+export type GetIpcRpcClientOptions = Pick<
+  GetSocketRpcClientParameters,
+  'reconnect'
+>
+
 const openingBrace = '{'.charCodeAt(0)
 const closingBrace = '}'.charCodeAt(0)
 
@@ -33,14 +39,21 @@ export function extractMessages(buffer: Buffer): [Buffer[], Buffer] {
 
 export type IpcRpcClient = SocketRpcClient<NetSocket>
 
-export async function getIpcRpcClient(path: string): Promise<IpcRpcClient> {
+export async function getIpcRpcClient(
+  path: string,
+  options: GetIpcRpcClientOptions = {},
+): Promise<IpcRpcClient> {
+  const { reconnect } = options
+
   return getSocketRpcClient({
-    async getSocket({ onResponse }) {
+    async getSocket({ onError, onOpen, onResponse }) {
       const socket = connect(path)
 
       function onClose() {
         socket.off('close', onClose)
         socket.off('message', onData)
+        socket.off('error', onError)
+        socket.off('connect', onOpen)
       }
 
       let lastRemaining = Buffer.alloc(0)
@@ -57,6 +70,8 @@ export async function getIpcRpcClient(path: string): Promise<IpcRpcClient> {
 
       socket.on('close', onClose)
       socket.on('data', onData)
+      socket.on('error', onError)
+      socket.on('connect', onOpen)
 
       // Wait for the socket to open.
       await new Promise<void>((resolve, reject) => {
@@ -84,6 +99,7 @@ export async function getIpcRpcClient(path: string): Promise<IpcRpcClient> {
         },
       } as Socket<{}>)
     },
+    reconnect,
     url: path,
   })
 }