Electrum for Templecoin

[temple]

I currently study the code for electrum client and server. They are nice.
However, when I try to port it to my own coin , Templecoin, I encounter some problem.

I don't know if that the right place to ask.

The source code is here:
https://github.com/9cat/electrum-tpc


It is running fine, and can receive coins and send coins.
But it is not able to verify coins.

The worst is that I don't know if it is a server side issue for the client issue.
And I am doing poor at python coding.

If anyone can help on this I could reward ₮100 as a bounty (electrum running successfully and fully functioning, same as bitcoin for the current version)

If you don't have time, please point me out which .py file I should modify to fix this verification issue.

[mr_burdell]

I would start here: https://github.com/9cat/electrum-tpc/blob/templecoin/lib/blockchain.py#L253

You left everything the same as Litecoin.  I know nothing about templecoin, but I assume it's not a complete clone of Litecoin.

[temple]

I would start here: https://github.com/9cat/electrum-tpc/blob/templecoin/lib/blockchain.py#L253

You left everything the same as Litecoin.  I know nothing about templecoin, but I assume it's not a complete clone of Litecoin.

Thanks your reply.
I modify a little bit for the bitcoin.
It is megacoin + litecoin + own modification of getblock value;
However, I did not change a lot .

I try to spend some time to dig into this block chain part.

PS: there is a code:
 self.headers_url = 'http://headers.electrum-ltc.org/blockchain_headers'

How can I made this headers for my own coin? if anyone know, reply this too.
https://github.com/9cat/electrum-tpc/blob/templecoin/lib/blockchain.py#L41

[temple]

OK, I guess I got the blockchain_headers.

It is under the levelDB.

And when I change that url above. it verified the previous payments. However, I can't see the blockchain is increasing when the time goes.

[temple]

I finally got it work with security hole there.might need to dig into it. but might help someone else like to play around it.


I don't know how to implement the KGW (KimotoGravityWell)
for electrum:

https://github.com/9cat/templecoin/blob/templecoin/src/main.cpp#L1306

So I simply avoid to check bit for now.
If anyone know how to implement the KGW part. I love to see if . and I will off TPC100 bounty for it


----------------------------------------------------------------

 def verify_chain(self, chain):

        first_header = chain[0]
        prev_header = self.read_header(first_header.get('block_height') -1)
       
        for header in chain:

            height = header.get('block_height')

            prev_hash = self.hash_header(prev_header)
            bits, target = self.get_target(height/2016, chain)
            _hash = self.pow_hash_header(header)
         
         
            print_msg("prev_hash", prev_hash)
            print_msg("prev_block_hash", header.get('prev_block_hash'))
            print_msg("bits", bits)
            print_msg("bits.header", header.get('bits'))

            try:
                assert prev_hash == header.get('prev_block_hash')
                #assert bits == header.get('bits')
                #assert int('0x'+_hash,16) < target
            except Exception:
                return False

            prev_header = header

        return True

[mr_burdell]

I've previously got KGW working with vertcoin, but it's quite slow due to the way KGW works (perhaps someone else could figure out how to speed up the code).

See here: https://github.com/wozz/electrum-vert/blob/master/lib/blockchain.py#L284

I assume you'll need to modify quite a bit of code to get this working correctly.

[mr_burdell]

BTW, your "security hole" is basically disabling SPV completely.

[temple]

BTW, your "security hole" is basically disabling SPV completely.

I tried to make it working at least.

But may I know the SPV , is it stands for simple payment verfication?
If I block those part. what's the major impact for it?

double spending?
or attacking?

[temple]

I guess it kind out of ability to finish all the coding.

Wish someone able to do it with a small cash as the following link:
https://www.freelancer.com/projects/Linux-Python/Implement-electrum-wallet-for-Templecoin.html


If someone could do the best job with lower bid.
I would offer additional TPC$200 as bounty for this job done.


-Temple

[temple]

ok I finally figure 2 things:


1. there so many SCAM on the freelancer. if don't post a good amount of offer, I guess all of SCAM.


2. I finally figure the solution myself. and have upload to github. if anyone interesting. other VertCoin implementation. I use a pretty silly way.
directly porting C++ to python, with similar variables. easy to understand, but not optimized yet.

https://github.com/9cat/electrum-tpc/blob/kgw/lib/blockchain.py#L300