We are going to start with a simple todo cli application with a straight-forward implementation.
The source of this code comes from Geeks for Geeks.
Starting Code
import sys
import datetime
def help():
sa = """Usage :-
$ ./todo add "todo item" # Add a new todo
$ ./todo ls # Show remaining todos
$ ./todo del NUMBER # Delete a todo
$ ./todo done NUMBER # Complete a todo
$ ./todo help # Show usage
$ ./todo report # Statistics"""
sys.stdout.buffer.write(sa.encode('utf8'))
def add(s):
f = open('todo.txt', 'a')
f.write(s)
f.write("\n")
f.close()
s = '"'+s+'"'
print(f"Added todo: {s}")
def ls():
try:
nec()
l = len(d)
k = l
for i in d:
sys.stdout.buffer.write(f"[{l}] {d[l]}".encode('utf8'))
sys.stdout.buffer.write("\n".encode('utf8'))
l = l-1
except Exception as e:
raise e
def deL(no):
try:
no = int(no)
nec()
with open("todo.txt", "r+") as f:
lines = f.readlines()
f.seek(0)
for i in lines:
if i.strip('\n') != d[no]:
f.write(i)
f.truncate()
print(f"Deleted todo #{no}")
except Exception as e:
print(f"Error: todo #{no} does not exist. Nothing deleted.")
def done(no):
try:
nec()
no = int(no)
f = open('done.txt', 'a')
st = 'x '+str(datetime.datetime.today()).split()[0]+' '+d[no]
f.write(st)
f.write("\n")
f.close()
print(f"Marked todo #{no} as done.")
with open("todo.txt", "r+") as f:
lines = f.readlines()
f.seek(0)
for i in lines:
if i.strip('\n') != d[no]:
f.write(i)
f.truncate()
except:
print(f"Error: todo #{no} does not exist.")
def report():
nec()
try:
nf = open('done.txt', 'r')
c = 1
for line in nf:
line = line.strip('\n')
don.update({c: line})
c = c+1
print(
f'{str(datetime.datetime.today()).split()[0]} Pending : {len(d)} Completed : {len(don)}')
except:
print(
f'{str(datetime.datetime.today()).split()[0]} Pending : {len(d)} Completed : {len(don)}')
def nec():
try:
f = open('todo.txt', 'r')
c = 1
for line in f:
line = line.strip('\n')
d.update({c: line})
c = c+1
except:
sys.stdout.buffer.write("There are no pending todos!".encode('utf8'))
if __name__ == '__main__':
try:
d = {}
don = {}
args = sys.argv
if(args[1] == 'del'):
args[1] = 'deL'
if(args[1] == 'add' and len(args[2:]) == 0):
sys.stdout.buffer.write(
"Error: Missing todo string. Nothing added!".encode('utf8'))
elif(args[1] == 'done' and len(args[2:]) == 0):
sys.stdout.buffer.write(
"Error: Missing NUMBER for marking todo as done.".encode('utf8'))
elif(args[1] == 'deL' and len(args[2:]) == 0):
sys.stdout.buffer.write(
"Error: Missing NUMBER for deleting todo.".encode('utf8'))
else:
globals()[args[1]](*args[2:])
except Exception as e:
s = """Usage :-
$ ./todo add "todo item" # Add a new todo
$ ./todo ls # Show remaining todos
$ ./todo del NUMBER # Delete a todo
$ ./todo done NUMBER # Complete a todo
$ ./todo help # Show usage
$ ./todo report # Statistics"""
sys.stdout.buffer.write(s.encode('utf8'))
This app uses the name todo, but we will start with this file in todo.py to try to replicate a beginner's script. If you would like to use this simply as todo, you will have to add an interpreter shebang and make the file executable.
#!/usr/bin/env python3
chmod a+x ./todo
Feel free to do this if you would like, but we are going to take a simpler approach. Instead, we will move forward with todo.py.
Make this a Poetry project
To turn this into a poetry project, we need to move this from a file to a directory.
First we make the directory.
mkdir todo-app
Then we move our python file in the new directory.
mv todo.py todo-app/todo.py
Now we navigate to the directory.
cd todo-app
Initialize the new poetry project.
poetry init
# This command will guide you through creating your pyproject.toml config.
# Package name [todo-app]:
# Version [0.1.0]:
# Description []:
# Author [Ian Johnson <tacoda@hey.com>, n to skip]:
# License []:
# Compatible Python versions [^3.12]:
# Would you like to define your main dependencies interactively? (yes/no) [yes] no
# Would you like to define your development dependencies interactively? (yes/no) [yes] no
# Generated file
# [tool.poetry]
# name = "todo-app"
# version = "0.1.0"
# description = ""
# authors = ["Ian Johnson <tacoda@hey.com>"]
# readme = "README.md"
# [tool.poetry.dependencies]
# python = "^3.12"
# [build-system]
# requires = ["poetry-core"]
# build-backend = "poetry.core.masonry.api"
# Do you confirm generation? (yes/no) [yes]
Here, I accept most of the defaults. Enter or Return will accept the default for each of these prompts. The default value is given in square brackets at the end of a prompty. I specifically chose not to define my dependencies interatively to work through it.
Run the Project
We can run commands in the virtual environment set up by poetry on a one-by-one basis by using the run subcommand.
poetry run python todo.py
# Creating virtualenv todo-app-7hL1Y5Tc-py3.12 in /Users/ianjohnson/Library/Caches/pypoetry/virtualenvs
# Usage :-
# $ ./todo add "todo item" # Add a new todo
# $ ./todo ls # Show remaining todos
# $ ./todo del NUMBER # Delete a todo
# $ ./todo done NUMBER # Complete a todo
# $ ./todo help # Show usage
# $ ./todo report # Statistics
Run a Shell
In addition to running commands one at a time, we can enter a virual environment shell to interact with our project in a more familiar way.
poetry shell
# Spawning shell within /Users/ianjohnson/Library/Caches/pypoetry/virtualenvs/todo-app-7hL1Y5Tc-py3.12
python todo.py
# Usage :-
# $ ./todo add "todo item" # Add a new todo
# $ ./todo ls # Show remaining todos
# $ ./todo del NUMBER # Delete a todo
# $ ./todo done NUMBER # Complete a todo
# $ ./todo help # Show usage
# $ ./todo report # Statistics
Great! We have now wrapped our script inside Poetry. In addition to our todo.py script, we now have a pyproject.toml file that was generated by Poetry.
Key Takeaways
- Wrap Python scripts with Poetry using
init - Poetry uses a
pyproject.tomlfile - Run commands using
run - Enter a virtual environment shell using
shell
Top comments (0)