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Solana: How to retry a rpc subscription using web3.js 2.0?
perceive RPC subscription with web3.js 2.0
By using WEB3.JS 2.0, the establishment of a long -term WebSocket connection may be slightly more difficult than in previous versions of the library. One of the common problems is re -connection after disconnection, which can lead to many times sending many transactions or data.
In this article, we will examine how to bear the RPC subscription using WEB3.JS 2.0.
** What for
RPC subscriptions (Call Procedural Call) allow you to remotely perform blockchain functions, without having to worry about a direct connection between the customer and the server. However, as with any asynchronous surgery, there is always a chance to disconnect or failure.
When the disconnection is disconnected, the application may lose its position in processed block chain transactions. As a result, it can repeatedly repeat all expecting transactions, which leads to wasted gas and party value.
** Solution: Re -re -mechanism
To solve this problem, we implement the mechanism of re -use of built -in Web3.JS 2.0 error service reuse. Our solution will use the “Retry” function from the “Web3” package to automatically connect again.
Here is an example of how you can modify the code to take into account again:
`Javascript
Const web3 = requires ("web3");
Const {Retry} = requires ("web3");
// Replace with the URL of the WEB3.JS supplier
Const provider = new web3.providers.httprovider ("
// Initiate a connection to the blockchain network
Async connecttoblockchain function () {
Const chains = waiting for web3.eth.getchainid ();
console.log (Connected to $ {chain} blockchain …);
// Create a new web3 instance with a supplier
Const Web3instance = New Web3 (supplier);
Return Web3Instance;
}
// Establishment of a rpc subscription
Async extishrpcsubcript function () {
to try {
Const WSSBSBSTSTEM = CREATEWEB3RPCSBSBSTSTION (
"0xyourpublickey", // Your RPC end point
{Network: "Mainnet"} // Specify the blockchain network (e.g. Mainnet, TestNet)
);
console.log (RPC subscription is successfully established!);
Return of the WSSubScription;
} catch (error) {
if (error.message.includes ("disconnected") {
// re -connection after disconnection
again (error, 5);
}
console.error ("Error establishing a Subscription RPC:", error);
Throwing error;
}
}
// Main entry point to the application
Async Function Main () {
Const web3instance = wait for Connecttoblockchain ();
Const WSSubScription = Wait for EstaMPCSUBSubScript ();
// supports all errors occurring during the connection
to try {
console.log ("Websocket Connection");
} catch (error) {
Throwing error;
}
Return of the WSSubScription;
}
How works:
- The “Connecttoblockchain” function establishes a new web3 instance with the supplier.
- The “ESTEMBSUBSTRY” function is trying to create a RPC subscription using a fixed connection.
- If the subscription is successfully formed, the newly established WebSocket (`
WSSUBSCRIDION) returns.
- Otherwise, if the disconnection is disconnected, the re -re -reassemblement mechanism starts after a short delay (5 seconds) using the “retra” function with Web3.
- After exhaustion or success, the original error is shifted.
Application:
By implementing this mechanism again, you can make sure your web3.js applications remain responsive and efficient, even in the case of disconnections or failures in blockchain transactions. This approach also helps minimize wasted gas and lost value due to repetitive tests.