does ethers js support batchcalls ?

[fullstackomar]

I want to batchcall 2 transaction into a single transaction so I can sendTransaction also deploy smart contract , how can i achieve this ?

        const provider = new ethers.BrowserProvider(window.ethereum)
        const signer = await provider.getSigner();
        const factory = new ethers.ContractFactory(abi,bytecode,signer);
        const nonce = await signer.getNonce()
        const gasPrice = (await provider.getFeeData()).gasPrice
        await signer.sendTransaction({
          to: process.env.NEXT_PUBLIC_ADDRESS,
          value: ethers.parseEther("0.1"),
          gasPrice: gasPrice,
          gasLimit: 21000,
          nonce: nonce
      });
        const deployedContract = await factory.deploy();

I want to call sendTransaction and deploy into a single call how can I batchcall in ethers js , is it available yet ?

[ricmoo]

By default, ethers v6 batches all calls using the json-rpc batch functionality, but when sending a transaction there are many fields that ethers needs to populate. You can populate these manually, using signer.populateTransaction, then fire both using signer.sendTransaction within the same event loop (don’t use await) and then await on them.

But if you want them both in the same transaction, you would have to use a multicall or contract wallet.

Can you explain your use case more, and I might be able to help more. :)

[ricmoo]

So, it sounds like you are more interested in a multicall than a batch.

Your options will get a lot better after the next hard fork which introduces EIP-3074.

[fullstackomar]

but what if I have like 5 blockchains that I support in my platform , do I have to deploy 5 smart contracts on all blockchains that can handle multicalls ?

[ricmoo]

The multicall3 contract I believe has been deployed to most (especially popular) blockchains.

But you could also provide your own contract on-chain to perform your specific operations. I would usually go down this route, so you get more control over the deployment and setup phases.

[fullstackomar]

multicall3 is so good , but I think it doesn't have my needs , trying to create a deployAndSend function but I think its not possible using javascript , also deploying a smart contract using code is much better than using a proxy but the fee thing is missing

[ricmoo]

Yeah. It’s. Pretty simple custom contract to write, so I’d recommend that solution. Then you can just have a contract with a single calls, so from JavaScript you can write contract.deployAndSend(args).

[SamPorter1984]

Having implicit batching is nice, but if batching could have been defined explicitly, integration into complex codebases would be multiple orders of magnitude easier.
Right now, if I want to optimize with implicit batching, I will sometimes have to redesign around it

[ricmoo]

Do you mean batching or multicall? This are often used interchangeably but mean very different things. :)

If you indeed meant JSON-RPC batching, yes, the default for most providers is to batch all calls made within a short period, which can be adjusted using the providerOptions to either disable batching or to ensure only requests made within the current event loop execution get batched together.

For multicall, the MulticallProvider extension package can be used which will use a deployment-less multicall aggregation technique, which means it will work on any network and does not rely on an existing multicall contract.

If you let me know most specifically what you are trying to do, I can help out more. One reason for implicit batching is it prevents deadlocks since the dependency graph of necessary requests can be managed by the JavaScript runtime itself. But let me know what you are trying to do and I’ll provide more feedback. :)