Constructing, signing, and pushing a Bitcoin transaction by using pybitcointools with Python

OK, so first off:

Use Python 2.7; there's numerous pieces of code which doesn't work with Python 3.4, namely make_request
Check out this pybitcointools fork, as there's a lot of added functionality (see the README.txt file)

The functions you've named work as so:

mktx(ins, outs) where ins is an array of "hexTxIdString:index" and outs is an array of {"value": 12345, "address": 1base58addressString}
mksend(ins, outs, txfee, 1changeAddress) where txfee is again in Satoshis
- sign(unsignedtx, index to sign, privkey for utxo) where index is the input index to sign

We'll start by making the ins:

utxos = [(utxo_txid, utxo_index), (txid2, i2)....]
ins = ["%s:%d" % utxo for utxo in utxos]
change_addr = "1thisIsAChangeAddressYouOwn123"
txfee = int(0.45 * len(ins) * 10000) # you may want to check this 10000 value, it could be 100000
rawtx = mksend(ins, txfee, change_addr)

Right, so let's assume, you have the UTXOs' TxID and corresponding vout for each private key. Make an dict of privkeys ={ 'TxID:vout' : privkey, 'TxID2:vout2': privkey2 } Then finally, signall(rawtx, privkeys) to get your signed Tx. Then to broadcast it, use pushtx(signedTx, source="bci") or pushtx(signedTx, "testnet", source="blockr") for Testnet. Done!

Wizard Of Ozzie

Posted 2015-08-21T22:42:42.023

Reputation: 4 535

What function are you using to easily get the values for utxos ? What's the best way to go about it? – encodex – 2015-08-22T13:45:01.137

I use that fork I linked; you can filter a list of the history/unspent, then use get_outputs to return the string required. Have had this exact same issue – Wizard Of Ozzie – 2015-08-22T13:46:29.963

In the code block above you have there doesn't show you using mktx but you explained it above. – encodex – 2015-08-22T13:52:54.650

address = 164QpJNZPYtHNVZiNmzuG2yEeWok2UfymZ

So, I should use history(address) rather than unspent(address) ?

It doesn't look like history gives me the unspent_output hash? I'm still really, really confused because it seems like in the pybitcointools example they do it in a completely different way.

I'm trying to imagine how to do it from the very beginning with creating my variables and everything.

"2e204724677fb2f6cc80ed4cc92f0d068e8ec7774f49bfbf4b075aea76154f2b:0"

is the outspent output and index, am I right?

Getting my ass kicked with formatting on here for some reason. – encodex – 2015-08-22T14:23:41.407

Actually, you're right, use unspent: unspent_1 = [unspent(privtoaddr(x)) for x in privs]. I believe that'll return an array of "txid:index", which you'll need to filter through for unspents which have len>1, with [x for y in unspent_1 for x in y] which returns the flattened list. Re: mktx, mksend calls mktx, it just works out the difference and refunds that to a change address – Wizard Of Ozzie – 2015-08-22T15:07:25.797

I'll give it a whirl here in a bit. Thanks for all the help. – encodex – 2015-08-22T15:28:50.003

@encodex cool, I'll edit my answer shortly to show you exactly the process – Wizard Of Ozzie – 2015-08-23T04:56:22.190

Constructing, signing, and pushing a Bitcoin transaction by using pybitcointools with Python

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