Power outage resulted in server error on restart (blank config.json, steps taken to recover)

[kdmukai]

My setup: Running specter-desktop on a Raspi4 via supervisord for auto restarts. Using the "Multiple Users" feature to keep different wallets more separated so I don't accidentally mix funds.

Power went out last night. Accessing today via browser just returns a server error.

The ~/.specter/config.json is blank. So is the .bkp. I delete both and restart specter-desktop.

A new, usable config.json is generated but watching the logs it's saying it can't load any of my wallets: Couldn't load wallet xxxxx into core.Silently ignored! RPC error: Request error: Wallet specterac151d0eb190f435/xxxxx not found.

Ah, that specter UID is brand new, courtesy of the new config.json. So I find my previous UID by looking at the my bitcoin node's wallet dir (~/.bitcoin/wallet). The specter wallets are "specter***" where that's the UID appended. I edit the specter config.json and change the UID back to what it had been. Restart specter-desktop.

Good, specter logs no longer complain and bitcoin node logs show that the wallets are loaded.

But I need to reinitialize the "Multiple Users" setting to restore access. Once I do so specter immediately picks up my user accounts. And I'm now I'm good.

Documenting all this here since there were some non-obvious steps.

Remaining work:

• No clue right now how the config.json AND its backup got wiped out.
• Need more bulletproofing around persistence.py; its json errors are what caused the server errors (though thankfully the stack trace made it pretty obvious what the problem was). If I don't get around to submitting a fix, should be a relatively easy one for someone to tackle.

  File "/home/kdmukai/.virtualenvs/specter-desktop-env/lib/python3.7/site-packages/cryptoadvance/specter/persistence.py", line 37, in read_json_file
  content = json.load(f)
  File "/usr/lib/python3.7/json/__init__.py", line 296, in load
  parse_constant=parse_constant, object_pairs_hook=object_pairs_hook, **kw)
  File "/usr/lib/python3.7/json/__init__.py", line 348, in loads
  return _default_decoder.decode(s)
  File "/usr/lib/python3.7/json/decoder.py", line 337, in decode
  obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python3.7/json/decoder.py", line 355, in raw_decode
  raise JSONDecodeError("Expecting value", s, err.value) from None
  json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

[ghost]

+1 - Just went through a similar experience on Specter 1.0.0 via getumbrel.com.

Lost power last night, and received a 500 Server Error this morning when attempting to access Specter.

Upon debugging, this error looks due to Specter attempting to load config.json even though it's contents had managed to have been wiped. The backup file was also empty. I deleted the files and let Specter recreate it on startup. Afterwards, I could see the Specter dashboard. My devices but the only wallet was gone. I had to create a new wallet from the JSON file located in the backup.zip I saved. After scanning the blockchain, things appeared to be working.

• The first issue appears to be that Specter is not actually prepared for a case when config.json file is empty. A specific exception should be thrown when that file is empty, instead of attempting to parse it as valid JSON.
• The second issue is what to do when that file is indeed empty. I suspect it is possible to auto-heal the file and reconnect it to the wallets and devices JSON, which appears 100% in tact even after entering this broken state.
• The third issue might be uncovered by asking why the config file is emptied in the first place? Why can devices auto-recover themselves but wallets must be manually healed?