Debugging Smart Contracts

Debugging Smart Contracts is a critical part of development.

This repo contains examples to demonstrate how a developer might approach debugging a Smart Contract using the Dryrun endpoint

Make sure you have the sandbox installed and running locally

Documentation to help understanding the tools available is here

Contracts

• contracts/application.py - Beaker PyTeal Application
• contracts/artifacts/approval.teal - The approval program generated from the Beaker application
• contracts/artifacts/clear.teal - The clear program generated from the Beaker application
• contracts/artifacts/contract.json - The ARC4 ABI Contract specification from the Beaker application
• contracts/artifacts/DebugMe.json - The Beaker Application specification from the Beaker application

Usage

Setup

Clone this repo down

git clone git@github.com:algorand-devrel/debugging.git
cd debugging

Create a python virtual environment and install beaker-pyteal so we can rebuild the beaker application

$ python -m venv .venv
$ source .venv/bin/activate
(.venv)$ pip install beaker-pyteal

Python SDK

If using python, keep the virtual environment sourced and cd into the python directory then run the file main.py

(.venv)$ cd py
(.venv)$ python main.py

Proceed to debugging

JS SDK

If using the JS SDK, cd into the js directory and install the required modules

cd js
npm install

Then run the demo program

npm run demo

Proceed to debugging

Go SDK

go get
go run ./*.go

Goal/Tealdbg

When using the goal and tealdbg process each step is contained within its own file. You may debug the step by specifying an argument after the script e.g. ./0_deploy debug. Note this uses sandbox by default, but if you have a node running locally modify the code to remove the variable SB.

$ cd sh
$ ./0_deploy.sh
$ ./0_deploy.sh debug
$ ./1_bootstrap.sh
$ ./1_bootstrap.sh debug
$ ./2_transfer.sh
$ ./2_transfer.sh debug
$ ./3_withdraw.sh
$ ./3_withdraw.sh debug

Debugging

If you need to modify the contract logic, make sure the virtualenv is active and run:

(.venv)$ cd contracts
(.venv)$ python application.py

This will overwrite the teal programs and contract json file.

Follow this algorithm to debug:

While Broken:

    Create a transaction group
    
    Execute it

    If broken: 
        Create DryrunRequest object using SDK method

        Send DryrunRequest to algod

        Parse DryrunResponse object

        Print Stack Trace

        Inspect it

        Try a fixing something

happy hacking :)