private key - Using Bitcoin-ruby to make a transaction -

i posted question on bitcoin stack told may have better luck reposting here.

i having trouble bitcoin-ruby gem. following error when trying send money address have on test network:

/var/lib/gems/2.2.0/gems/bitcoin-ruby-0.0.7/lib/bitcoin/protocol/txout.rb:76:in pk_script=': undefined methodbytesize' nil:nilclass (nomethoderror)

i generating private key with:

def new_address  bitcoin::generate_address end 

and getting details private key with:

def key_details(prikey, pubkey)   #returns prikey, prikey_hash58, pubkey_hash58, pubkey_uncompressed, address hash   my_key = bitcoin::key.new(prikey, pubkey)   { prikey:prikey,      prikey_base58:my_key.to_base58,      pubkey_58:my_key.hash160,      pubkey: my_key.pub_uncompressed,      address:my_key.addr   } end 

the code have send money myself follows:

require 'bitcoin' require_relative 'utilities.rb' require 'open-uri'  bitcoin.network = :testnet3  def build_transaction(prev_tx, prev_out_index, key, value, addr, message)   include bitcoin::builder    new_tx = build_tx |t|     t.input |i|       i.prev_out prev_tx       i.prev_out_index prev_out_index       i.signature_key key     end     t.output |o|       o.value value        o.script {|s| s.type :address; s.recipient addr }     end   end end  def prev_tx(prev_hash, network)   if network == "testnet3"     prev_tx = bitcoin::p::tx.from_json(open("http://test.webbtc.com/tx/#{prev_hash}.json"))   else     prev_tx = bitcoin::p::tx.from_json(open("http://webbtc.com/tx/#{prev_hash}.json"))   end end  def key(publ_key, priv_key)   key = bitcoin::key.new(priv_key, publ_key) end  def bin_to_hex(s)   s.unpack('h*').first end  #transaction inputs priv_key = "private_key" publ_key = "public_key_long_format" address = "address" previous_tx = "previous_tx_hash"  # generate tx info off inputs key = bitcoin::key.new(priv_key, publ_key) prev_tx = prev_tx(previous_tx, "testnet3") prev_out_index = 1 tx_value = prev_tx.outputs[prev_out_index].value  # build new tx tx = build_transaction(prev_tx, prev_out_index, key, tx_value, address, "hello")  # # puts tx.to_json puts bin_to_hex(tx.to_payload) 

does know how solve error?

it turned out couple of issues. here learned along way:

the tx json data used build prev_tx object needs have output value string. sites use number instead.

the key object doesn't form correctly. whatever reason, have address can generated using private key bitcoin::key.new. if supply private , public key address associated key object wrong. different addresses, isn't case. important check address of key object after generating object.

it important make sure addresses / keys generated on testnet3 used 1 another. had situation thought generated testnet3 private key, didn't. thus, testnet3 tx wasn't working. , vice versa normal bitcoin network.

lastly, it's important verify output address position. 0 or 1, isn't case...