How to rehydrate a transaction serialized in XDR to a transaction object that can be signed and submitted, with the JavaScript sdk?

Question

The Transaction class has a .toXDR() method, but I don't see a fromXDR method.

I want to persist transactions in XDR base64, then load them, sign them, and send them.

There is a mention of a fromXDR method in the Transaction class here:

get Transaction object from xdr base64 string

but it's not in the doc: https://stellar.github.io/js-stellar-sdk/Transaction.html or even in the code...

Answer 1

You pass it directly in the constructor. This is described in the doc you linked to:

Parameters: envelope string | xdr.TransactionEnvelope

So do this:

// `transactionXDR` is a string from the person generating the transaction
const transaction = new Transaction(transactionXDR, networkPassphrase);

See also the docs for adding a signature to a transaction sent to you from someone else.