sdressler / plpgsql-pydebug

A Python PL/pgSQL CLI debugger

PL/pgSQL PyDebug

This is a CLI debugger for PL/pgSQL. It is in its early stages and rather archaic. It does make use of the pldbgapi extension for PostgreSQL. You can typically install it from the main PG repository.

Usage

1. Checkout from GitHub
2. Install requirements: pip3 install -r requirements.txt
3. Ensure you have the pldbgapi extension installed (it will warn you if not)
4. Start a debug session: ./run.py --dsn <dsn>. The <dsn> is the complete connection string to your running PostgreSQL instance.
5. Start to debug a PL/pgSQL function by calling run <function call> (see below).

Shortcomings aka the list of shame

• Output could be prettier / more readable.
• Not everything tested.
• Error handling might be incomplete, it could bail out and leave connections open.
• source, brset commands do not yet work with other functions than the active target functions. In other words: you can use them only on functions which do not call other functions respectively you can step into them but not show their source or set breakpoints.
• Not all commands from pldbgapi implemented.

Commands aka the list of fame

Currently, the following commands are available. There is no extensive syntax checking as of now, so you'll maybe run into trouble here and there.

• run <function call> starts debugging, ensure that <function call> is complete with all arguments, i.e. like run example_function_1(2).
• stop stops debugging.
• continue causes the execution to proceed to the next breakpoint.
• vars displays all variables of the current frame.
• si step-into, step into a function call, stop at the next executable instruction/breakpoint.
• so step-over, step over a function call, stop at the next executable instruction/breakpoint.
• source show the source of the current target function. Does not yet take into account that you could have nested functions.
• stack show the current stack.
• brshow show all active breakpoints.
• brset <line> set a breakpoint in the current target function at the given line. Caution: does not work with nested functions yet.
• exit exits the debugger.