Python Bitcoin Client
Switch branches/tags
Nothing to show
Clone or download
Pull request Compare This branch is 325 commits behind samrushing:master.
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.


Caesure: a python bitcoin client

Help Fund This Project! 1Ncui8YjT7JJD91tkf42dijPnqywbupf7w

note: this is *not* a JSON/RPC client, it's an implementation of the bitcoin protocol.

requirements: a relatively recent python, probably 2.5+ or so
either: A) an openssl library.
        B) the pure-python ecdsa package.

I have tested this code using openssl on osx 10.6 (64-bit), linux ubuntu (32-bit), and freebsd-7 (64-bit).


It's a pun on the words Caesar and Seizure.  "Render unto Caesar..."


This code is fairly close to being able to be a full participant on the network.

A couple of issues remain:
  1) orphan blocks are not always correctly handled.  I think the
     'embargo' concept may not work, and that it may be necessary to
     fully implement the idea of multiple alternative block chains.
     This has implications for the wallet: if there are multiple live
     chains, there are multiple possible wallet states.
  2) most of the 'protocol/network rules' are implemented, but not all of them.

I should say here that finishing this code could help the bitcoin
network tremendously, since its event-driven design makes it very
scalable.  This code should be able to connect simultaneously to many
hundreds of other nodes.  [The current bitcoin network is very
constrained, mostly because there is only one real implementation, and
it's a desktop client - this is a serious hindrance to bringing nodes
out from behind firewalls.  Servers should not have wallets, and they
should not be behind NATs and firewalls]

Another feature that would be really nice: to generalize the
block-chain-download process so that it can pull the block chain from
many nodes at once.  This would radically speed up the initialization
process for new nodes.

That said, as of Sep 2011, I have other priorities at the moment.
Perhaps if someone were to drop a little BTC into the donation bucket
I might be more interested in working on it.  As it stands not a
single donation has been made. (hint, hint).



$ python -c <your-external-ip-address> <other-ip-address>

I recommend connecting to a bitcoin client on your local machine, i.e.,

Once the client connects to the server it will start to download the block
database.  This will take a while, even if you're talking to localhost.

You can monitor the progress like this:

from another terminal:
$ telnet localhost 8023

you'll get a python prompt:

>>> the_block_db
<__main__.block_db instance at 0x43bdc8>
>>> db = _
>>> len(db.blocks)
>>> len(db.blocks)
>>> len(db.blocks)

IMPORTANT NOTE:  If you're running this on a multi-user machine, the python prompt
sitting on port 8023 will be a bad idea.  You have two choices: remove the line that
starts that server (near the bottom of the file, "m = monitor.monitor_server()"),
*or*, if your operating system supports it, bind the socket to an AF_UNIX socket and
telnet to that file.

The monitor interface is there to speed up development, and will eventually be
removed completely - probably replaced by a web admin interface.


web admin.

In client mode ('-c'), a web admin server is also started up on localhost:
try http://localhost:8380/admin/ (note: that trailing slash is important)

*** This is getting more useful, try it! ***



To use testnet, give the '-t' argument along with '-c'.  This will change several
global values, and should NOT impact your block database - it uses different
filenames.  HOWEVER you should use a different wallet path (the '-w' argument).

[wallet/addresses, etc.. are broken because of a prefix.  will roll in changes from
 joric once I figure out the socially acceptable way to do so on github]


To have access to a wallet, use: [-w <wallet-path>]

$ python -w wallet.bin


Rather than running a client, you can just start up python and play with the block
database.  Both the block database and wallet files are written in append-only mode,
so it's safe to open them read-only from another process, even while the client is

$ python -i -w wallet.bin 
reading block headers...
last block (135225): 0000000000000478bd4859949e91b44cc28e6a02e7bb2985df250751063e1d1f
>>> db['0000000000000478bd4859949e91b44cc28e6a02e7bb2985df250751063e1d1f']
<__main__.BLOCK instance at 0x3e7d508>
>>> b = _
>>> b.transactions[1]
<__main__.TX instance at 0x1e9508>
>>> tx = _
>>> tx
<__main__.TX instance at 0x1e9508>

dump a transaction:
>>> tx.dump()
hash: b1f8edbda61061be661731d3de215299f1356736502e52a0772a9259f7fd699d
inputs: 1
  0 13f23ebb1643b6faa02cf93f0bfd5c97c22bd76f3e9464ec61601d84f3afd404:0 493046022100b64136b383721bede39c6ff855339920928006c43d5f536d45c14ab401b736f8022100ee564e42001e3b071545e5f55bbcaa87eca7d731a339177701c40fa6d61510bf014104b3cd4b6d65ffea8fb7781e88a4e67d2f8104b80fb45ee50981940001d3a132584ea10a34a03224823492fd25344c50e40a52069df297da024ffb3175ec745021 4294967295
2 outputs
  0 30.00000000 142rU1TWaxZkrTbxvvLGY8VyKiEyYPtKZu
  1 10.00000000 1Q9vpsULCLxS7dLXGg9kcfG31DTTqnhoxy
lock_time: 0

fetch a block by number:
>>> db.num_block[135000]
>>> b = db[_]

dump all its transactions:
>>> for tx in b.transactions:
...     tx.dump()

--- verify a transaction ---

verify the first input of a transaction:
>>> tx.verify (0)

--- generate a new key/address ---

NOTE: if you send money to an address that you generate, be very careful
to preserve your wallet file!

>>> the_wallet.new_key()

>>> the_wallet['1AATJKbiuxUA6XJSJWSe6DVQx26ARdF1ex']
<__main__.KEY instance at 0x1e9f08>

*** ALPHA CODE.  This has been used for only a handful of transactions.
*** USE AT YOUR OWN RISK.  Don't send money you're not willing to lose!

--- receiving bitcoins ---
Just leave the client running.  Once the send shows up in a block, it will be seen
by the wallet and any associated outputs will be reflected in your wallet.

--- sending bitcoins ---
[this needs to be done via the back door so you have access to the client connection]
>>> the_wallet
<__main__.wallet instance at 0x43b9e0>
>>> w = _
>>> w.total_btc

This will create a TX object
>>> w.build_send_request (6000000, '16LQbU1mTAHGgPkYWzqisF3ntxv91TdV3j') 
input 5000000
input 1000000
<__main__.TX instance at 0x3e838f0>
>>> tx = _
>>> tx.dump()
hash: eaca9674e313d2e369baecf610648f64f5bb4a6ba164be3387c7af9df48112b7
inputs: 2
  0 350784530...0dc18a6:1 49304502206f60...a745a51e4 4294967295
  1 12e0b9d6c...1cd4dca:1 4930440220236a...3b1ef50f3 4294967295
1 outputs
  0 0.06000000 16LQbU1mTAHGgPkYWzqisF3ntxv91TdV3j
lock_time: 0

You should verify the inputs before sending on...
>>> tx.verify (0)
>>> tx.verify (1)

>>> packet = make_packet ('tx', tx.render())

This will actually send the packet.
>>> bc
<__main__.connection connected '' at 0x458af8>
>>> bc.push (packet)

Any change that's sent back to you will be acknowledged once it makes it into
a block.