Coredumps from json parsing on chat branch

[leto]

I seem to be getting coredumps very often now on my chat branch. It is not clear what RPC or whatever is causing it:

RPC: "getinfo" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"getinfo\"}"
Timer timeout!
Sent ping,  23  bytes
RPC: "z_getoperationstatus" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"z_getoperationstatus\"}"
Websocket received msg:  "{\n    \"ping\": \"ping\"\n}\n"
processMessage message
Timer timeout!
Sent ping,  23  bytes
Websocket received msg:  "{\n    \"ping\": \"ping\"\n}\n"
processMessage message
RPC: "getinfo" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"getinfo\"}"
RPC: "z_getoperationstatus" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"z_getoperationstatus\"}"
RPC: "getinfo" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"getinfo\"}"
RPC: "z_getoperationstatus" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"z_getoperationstatus\"}"
RPC: "getinfo" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"getinfo\"}"
RPC: "z_getoperationstatus" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"z_getoperationstatus\"}"
RPC: "getinfo" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"getinfo\"}"
RPC: "z_getoperationstatus" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"z_getoperationstatus\"}"
RPC: "getinfo" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"getinfo\"}"
RPC: "z_getoperationstatus" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"z_getoperationstatus\"}"
RPC: "getinfo" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"getinfo\"}"
"{\"error\":{\"code\":-5,\"message\":\"Invalid or non-wallet transaction id\"},\"id\":\"gettx\",\"result\":null}"
"Error transferring http://127.0.0.1:18031 - server replied: Internal Server Error"
"{\"error\":{\"code\":-5,\"message\":\"Invalid or non-wallet transaction id\"},\"id\":\"gettx\",\"result\":null}"
"Error transferring http://127.0.0.1:18031 - server replied: Internal Server Error"
Timer timeout!
Sent ping,  23  bytes
RPC: "z_getoperationstatus" "{\"id\":\"42\",\"jsonrpc\":\"1.0\",\"method\":\"z_getoperationstatus\"}"
Websocket received msg:  "{\n    \"ping\": \"ping\"\n}\n"
processMessage message
"{\"error\":{\"code\":-5,\"message\":\"Invalid or non-wallet transaction id\"},\"id\":\"gettx\",\"result\":null}"
"Error transferring http://127.0.0.1:18031 - server replied: Internal Server Error"
Timer timeout!
Sent ping,  23  bytes
Websocket received msg:  "{\n    \"ping\": \"ping\"\n}\n"
processMessage message
terminate called after throwing an instance of 'nlohmann::detail::type_error'
  what():  [json.exception.type_error.302] type must be number, but is null
Aborted (core dumped)

[leto]

Full backtrace from the coredump shows the culprit: https://gist.github.com/leto/2891b5384125d783dc6e710199796d39

#11 0x00000000004908d0 in RPC::refreshReceivedZTrans(QList<QString>):......
    at src/rpc.cpp:512

We likely need to catch exceptions from our JSON library but nothing is there to catch it, so an exception from JSON parsing bubbles all the way up to the main call stack.

[leto]

We now use QT json lib on master, so we will merge that in and get new bugz soon