how to estimate fee?

[weishirongzhen]

I can use json rpc payment_queryFeeDetails or payment_queryInfo to query fee before, but I found these two api are error with "data" -> "Execution failed: Execution aborted due to trap: wasm trap: wasmunreachableinstruction executed..." now, and I found some doc about below method, but it looks like polkadart are not contain them?, any help?

payment

queryFeeDetails(extrinsic: Bytes, at?: BlockHash): FeeDetails

• interface: api.rpc.payment.queryFeeDetails
• jsonrpc: payment_queryFeeDetails
• summary: Query the detailed fee of a given encoded extrinsic
• deprecated: Use api.call.transactionPaymentApi.queryFeeDetails instead

  queryInfo(extrinsic: Bytes, at?: BlockHash): RuntimeDispatchInfoV1

• interface: api.rpc.payment.queryInfo
• jsonrpc: payment_queryInfo
• summary: Retrieves the fee information for an encoded extrinsic
• deprecated: Use api.call.transactionPaymentApi.queryInfo instead

[leonardocustodio]

You need to send the full encoded extrinsic. You can use a fake signature if you want to do that before really signing it.