Previously, generally, in case of any error, commands would raise a generic "Exception()" and the CLI/RPC would convert that and return it as `str(e)`.
With this change, we now distinguish "user-facing exceptions" (e.g. "Password required" or "wallet not loaded") and "internal errors" (e.g. bugs).
- for "user-facing exceptions", the behaviour is unchanged
- for "internal errors", we now pass around the traceback (e.g. from daemon server to rpc client) and show it to the user (previously, assuming there was a daemon running, the user could only retrieve the exception from the log of that daemon). These errors use a new jsonrpc error code int (code 2).
As the logic only changes for "internal errors", I deem this change not to be compatibility-breaking.
----------
Examples follow.
Consider the following two commands:
```
@command('')
async def errorgood(self):
from electrum.util import UserFacingException
raise UserFacingException("heyheyhey")
@command('')
async def errorbad(self):
raise Exception("heyheyhey")
```
----------
(before change)
CLI with daemon:
```
$ ./run_electrum --testnet daemon -d
starting daemon (PID 9221)
$ ./run_electrum --testnet errorgood
heyheyhey
$ ./run_electrum --testnet errorbad
heyheyhey
$ ./run_electrum --testnet stop
Daemon stopped
```
CLI without daemon:
```
$ ./run_electrum --testnet -o errorgood
heyheyhey
$ ./run_electrum --testnet -o errorbad
heyheyhey
```
RPC:
```
$ curl --data-binary '{"id":"curltext","jsonrpc":"2.0","method":"errorgood","params":[]}' http://user:pass@127.0.0.1:7777
{"id": "curltext", "jsonrpc": "2.0", "error": {"code": 1, "message": "heyheyhey"}}
$ curl --data-binary '{"id":"curltext","jsonrpc":"2.0","method":"errorbad","params":[]}' http://user:pass@127.0.0.1:7777
{"id": "curltext", "jsonrpc": "2.0", "error": {"code": 1, "message": "heyheyhey"}}
```
----------
(after change)
CLI with daemon:
```
$ ./run_electrum --testnet daemon -d
starting daemon (PID 9254)
$ ./run_electrum --testnet errorgood
heyheyhey
$ ./run_electrum --testnet errorbad
(inside daemon): Traceback (most recent call last):
File "/home/user/wspace/electrum/electrum/daemon.py", line 254, in handle
response['result'] = await f(*params)
File "/home/user/wspace/electrum/electrum/daemon.py", line 361, in run_cmdline
result = await func(*args, **kwargs)
File "/home/user/wspace/electrum/electrum/commands.py", line 163, in func_wrapper
return await func(*args, **kwargs)
File "/home/user/wspace/electrum/electrum/commands.py", line 217, in errorbad
raise Exception("heyheyhey")
Exception: heyheyhey
internal error while executing RPC
$ ./run_electrum --testnet stop
Daemon stopped
```
CLI without daemon:
```
$ ./run_electrum --testnet -o errorgood
heyheyhey
$ ./run_electrum --testnet -o errorbad
0.78 | E | __main__ | error running command (without daemon)
Traceback (most recent call last):
File "/home/user/wspace/electrum/./run_electrum", line 534, in handle_cmd
result = fut.result()
File "/usr/lib/python3.10/concurrent/futures/_base.py", line 458, in result
return self.__get_result()
File "/usr/lib/python3.10/concurrent/futures/_base.py", line 403, in __get_result
raise self._exception
File "/home/user/wspace/electrum/./run_electrum", line 255, in run_offline_command
result = await func(*args, **kwargs)
File "/home/user/wspace/electrum/electrum/commands.py", line 163, in func_wrapper
return await func(*args, **kwargs)
File "/home/user/wspace/electrum/electrum/commands.py", line 217, in errorbad
raise Exception("heyheyhey")
Exception: heyheyhey
```
RPC:
```
$ curl --data-binary '{"id":"curltext","jsonrpc":"2.0","method":"errorgood","params":[]}' http://user:pass@127.0.0.1:7777
{"id": "curltext", "jsonrpc": "2.0", "error": {"code": 1, "message": "heyheyhey"}}
$ curl --data-binary '{"id":"curltext","jsonrpc":"2.0","method":"errorbad","params":[]}' http://user:pass@127.0.0.1:7777
{"id": "curltext", "jsonrpc": "2.0", "error": {"code": 2, "message": "internal error while executing RPC", "data": {"exception": "Exception('heyheyhey')", "traceback": "Traceback (most recent call last):\n File \"/home/user/wspace/electrum/electrum/daemon.py\", line 254, in handle\n response['result'] = await f(*params)\n File \"/home/user/wspace/electrum/electrum/commands.py\", line 163, in func_wrapper\n return await func(*args, **kwargs)\n File \"/home/user/wspace/electrum/electrum/commands.py\", line 217, in errorbad\n raise Exception(\"heyheyhey\")\nException: heyheyhey\n"}}}
```
Electrum - Lightweight Bitcoin client
Licence: MIT Licence
Author: Thomas Voegtlin
Language: Python (>= 3.8)
Homepage: https://electrum.org/
Getting started
(If you've come here looking to simply run Electrum, you may download it here.)
Electrum itself is pure Python, and so are most of the required dependencies, but not everything. The following sections describe how to run from source, but here is a TL;DR:
$ sudo apt-get install libsecp256k1-dev
$ python3 -m pip install --user ".[gui,crypto]"
Not pure-python dependencies
If you want to use the Qt interface, install the Qt dependencies:
$ sudo apt-get install python3-pyqt5
For elliptic curve operations, libsecp256k1 is a required dependency:
$ sudo apt-get install libsecp256k1-dev
Alternatively, when running from a cloned repository, a script is provided to build libsecp256k1 yourself:
$ sudo apt-get install automake libtool
$ ./contrib/make_libsecp256k1.sh
Due to the need for fast symmetric ciphers, cryptography is required. Install from your package manager (or from pip):
$ sudo apt-get install python3-cryptography
If you would like hardware wallet support, see this.
Running from tar.gz
If you downloaded the official package (tar.gz), you can run Electrum from its root directory without installing it on your system; all the pure python dependencies are included in the 'packages' directory. To run Electrum from its root directory, just do:
$ ./run_electrum
You can also install Electrum on your system, by running this command:
$ sudo apt-get install python3-setuptools python3-pip
$ python3 -m pip install --user .
This will download and install the Python dependencies used by
Electrum instead of using the 'packages' directory.
It will also place an executable named electrum in ~/.local/bin,
so make sure that is on your PATH variable.
Development version (git clone)
(For OS-specific instructions, see here for Windows, and for macOS)
Check out the code from GitHub:
$ git clone https://github.com/spesmilo/electrum.git
$ cd electrum
$ git submodule update --init
Run install (this should install dependencies):
$ python3 -m pip install --user -e .
Create translations (optional):
$ sudo apt-get install python3-requests gettext qttools5-dev-tools
$ ./contrib/pull_locale
Finally, to start Electrum:
$ ./run_electrum
Run tests
Run unit tests with pytest:
$ pytest electrum/tests -v
To run a single file, specify it directly like this:
$ pytest electrum/tests/test_bitcoin.py -v
Creating Binaries
Contributing
Any help testing the software, reporting or fixing bugs, reviewing pull requests and recent changes, writing tests, or helping with outstanding issues is very welcome. Implementing new features, or improving/refactoring the codebase, is of course also welcome, but to avoid wasted effort, especially for larger changes, we encourage discussing these on the issue tracker or IRC first.
Besides GitHub,
most communication about Electrum development happens on IRC, in the
#electrum channel on Libera Chat. The easiest way to participate on IRC is
with the web client, web.libera.chat.