AssertionError: assert len(string) == curve.baselen, (len(string), curve.baselen)

[ztnark]

I get the following error after running:

./bin/sync_wallets

Traceback (most recent call last):
  File "./client.py", line 137, in <module>
    main(docopt(__doc__, version='tinychain client 0.1'))
  File "./client.py", line 37, in main
    t.init_wallet(args.get('--wallet')))
  File "/Users/jeffkrantz/Apps/sandbox/tinychain/tinychain.py", line 1068, in init_wallet
    f.read(), curve=ecdsa.SECP256k1)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/ecdsa/keys.py", line 149, in from_string
    assert len(string) == curve.baselen, (len(string), curve.baselen)
AssertionError: (33, 32)

[jamesob]

Yeah, I've actually seen this sporadically in local development too. Given our pretty direct usage of ecdsa, I wonder if it's a problem there? The extent of what we do with the key bytes is a file(..., 'wb').write(), so I'm not sure where things could be going awry.

[jamesob]

At any rate, the easy workaround is to restart the containers which causes new wallet generation (as you've probably figured out). Would like to get to the bottom of this, though.

[jamesob]

Unable to reproduce locally, so I'm betting this has something to do with container -> host issues.

In [6]: def check_key():
   ...:     with open('/tmp/foo', 'wb') as f:
   ...:         f.write(ecdsa.SigningKey.generate(curve=ecdsa.SECP256k1).to_string())
   ...:     with open('/tmp/foo', 'rb') as f: 
   ...:         assert len(f.read()) == 32
   ...:         
   ...:         

In [7]: for i in range(10000):
   ...:     check_key()
   ...:     
   ...:     

[jamesob]

We could probably use binascii to encode/decode the on-disk private key to avoid this.

i have the same issue running on osx. renaming wallet1.dat and wallet2.dat and restarting the containers doesn't seem to help. it generates new wallets but spits out the same assert error.

[DerekRay]

We could use
docker cp Node2ID:/wallet.dat ./wallet2.dat
to replace
docker-compose exec node2 cat wallet.dat > wallet2.dat
This error may be caused by docker.

[DerekRay]

Just like this:
vim ./bin/sync_wallets

#!/bin/bash

docker-compose exec node1 cat wallet.dat > wallet1.dat
echo "Synced node1's wallet:"
./client.py balance --wallet wallet1.dat
echo

node2id=$(docker ps | grep 'node2' | awk '{print $1}')
docker cp ${node2id}:/wallet.dat ./wallet2.dat
echo "Synced node2's wallet:"
./client.py balance --wallet wallet2.dat