How to know the `branch` value while forging an operation using Taquito?

Question

0

I want to use forgeOperation function provided by '@taquito/rpc' to make a transfer between two tz1 accounts. I can estimate gasLimit, storageLimit and suggestedFee using '@taquito/taquito' estimate method. But how can we get branch field in an operation shown below:

{
  "branch": "BMHBtAaUv59LipV1czwZ5iQkxEktPJDE7A9sYXPkPeRzbBasNY8",
  "contents": [
    { "kind": "transaction",
      "source": "tz1KqTpEZ7Yob7QbPE4Hy4Wo8fHG8LhKxZSx",
      "fee": "50000",
      "counter": "3",
      "gas_limit": "200",
      "storage_limit": "0",
      "amount": "100000000",
      "destination": "tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN"
   } ]
}

Is it the hash of the current block we get by calling getBlock() function from '@taquito/rpc'? If it is, then in between the time of forging and injecting an operation if some other block got published, does this operation fail? Thanks in advance.

Answer 1

Is it the hash of the current block we get by calling getBlock()

Yes

if some other block got published, does this operation fail

Not sure, but I think no, because it's still on the same branch (old block points to next block), just a block older. You can inject a txn now with branch X, goes to mempool, doesn't get added to current block, but will get added to next block. In that case, the branch doesn't match the same as current, but it does match current's previous.