# Convert string to duration

I found myself wanting to convert a string to a duration (int), for some configuration.

Something you can call like this:

``````string_to_duration("1d", target="days")
string_to_duration("1d", target="hours")
string_to_duration("3m", target="hours")
string_to_duration("3m", target="minutes")
``````

The code :

``````from typing import Literal

def string_to_duration(value: str, target: Literal["days", "hours", "minutes"]):
"""Convert a string to a number of hours, days or minutes"""
num = int("".join(filter(str.isdigit, value)))

# It's not possible to convert from a smaller unit to a greater one:
# - hours and minutes cannot be converted to days
# - minutes cannot be converted to hours
if (target == "days" and ("h" in value or "m" in value.replace("mo", ""))) or (
target == "hours" and "m" in value.replace("mo", "")
):
msg = (
"Durations cannot be converted from a smaller to a greater unit. "
f"(trying to convert '{value}' to {target})"
)
raise ValueError(msg, value)

# Consider we're converting to minutes, do the eventual multiplication at the end.
if "h" in value:
num = num * 60
elif "d" in value:
num = num * 60 * 24
elif "w" in value:
num = num * 60 * 24 * 7
elif "mo" in value:
num = num * 60 * 24 * 30  # considers 30d in a month
elif "y" in value:
num = num * 60 * 24 * 365
elif "m" in value:
num = num
else:
raise ValueError("Invalid duration value", value)

if target == "hours":
num = num / 60
elif target == "days":
num = num / 60 / 24

return num
``````

#python, #conversion - Posté dans la catégorie code