The synchronizer's work is done from the network proxy's main loop.
A minor problem with the old synchronizer was that it considered itself
out of date if the network was out of date. This was too generic: the
network can have pending requests unrelated to the synchronizer. This
resulted in the synchronizer often unnecessarily flipping the wallet
between up-to-date and not-up-to-date, and causing unnecessary calls
to wallet.save_transactions(). This was observable when opening the
network dialog box: frequently just opening it would cause a wallet
status change and transaction flush, simply because the network dialog
sends a get_parameters() request. This rework of the synchronizer does
not have that issue.
This is somewhat cleaner as the proxy's pipe and network setup
was awkwardly interleaved. It also means network's constructor
is free to use both; currently some code is working around the
fact that the response queue doesn't exist in the constructor.
We store it in the config object instead of in the blockchain object.
The blockchain object now refers to its config, and calls refresh_height() to update it.
The network objects also refer to the config rather than the blockchain.
This is the first of many small steps to untangle the verifier from stored state and so
permit the history tab to work in offline mode. The refactoring will simultaneously clean
up a lot of accumulated cruft.
Neil Booth
ThomasV
Tafelpoot