This project is part of the Pyrustic Open Ecosystem.
Sometimes you need to know when the content of a data collection has changed.
Probed is a library that exposes three classes: ProbedDict, ProbedList and ProbedSet.
These classes are containers like the built-in Python containers (dict, list, set) which they subclass but with not a twist but two twists:
- be notified when the content of your data collection changes (if you wish to be notified);
- being able to put a probe into data collection to do more than just be notified.
Let's write a script to see Probed in action:
# script.py
from probed import ProbedList
def on_change(context):
msg = "\nThe {} operation changed the {} collection\n{}"
print(msg.format(context.operation, context.container, context.collection))
plist = ProbedList(on_change=on_change)
plist.append("hi")
plist.insert(1, "friend")Let's run the script:
$ python3 script.py
The append operation changed the list collection
['hi']
The insert operation changed the list collection
['hi', 'friend']Now, let's discover what the probe feature does and how to use it:
# script.py
from probed import ProbedSet
def probe(context):
# this probe will lower strings added to the collection
# also, the object None isn't allowed in the collection
if context.operation == "add":
if context.item is None:
context = None
else:
context.item = context.item.lower()
return context
pset = ProbedSet(probe=probe)
# add items
pset.add("RED")
pset.add(None)
pset.add("Green")
# print
print(pset) # {'red', 'green'}In the last script, the probe was used to control the items added to the data collection.
All operations that change the contents of the built-in containers are covered by probed.
Read the modules documentation !
The Shared data exchange and persistence library uses Probed to implement the autosave feature !
Discover Shared !
Probed is cross platform and versions under 1.0.0 will be considered Beta at best. It is built on Ubuntu with Python 3.8 and should work on Python 3.5 or newer.
$ pip install probed$ pip install probed --upgrade --upgrade-strategy eager