Is there a way to search for a string and copy text in front until it reaches a comma?

Question

I am new to python and wanted to store the recentAveragePrice inside a variable (from a string like this one)

{"assetStock":null,"sales":250694,"numberRemaining":null,"recentAveragePrice":731,"originalPrice":null,"priceDataPoints":[{"value":661,"date":"2022-08-11T05:00:00Z"},{"value":592,"date":"2022-08-10T05:00:00Z"},{"value":443,"date":"2022-08-09T05:00:00Z"}],"volumeDataPoints":[{"value":155,"date":"2022-08-11T05:00:00Z"},{"value":4595,"date":"2022-08-10T05:00:00Z"},{"value":12675,"date":"2022-08-09T05:00:00Z"},{"value":22179,"date":"2022-08-08T05:00:00Z"},{"value":15181,"date":"2022-08-07T05:00:00Z"},{"value":14541,"date":"2022-08-06T05:00:00Z"},{"value":15310,"date":"2022-08-05T05:00:00Z"},{"value":14146,"date":"2022-08-04T05:00:00Z"},{"value":13083,"date":"2022-08-03T05:00:00Z"},{"value":14460,"date":"2022-08-02T05:00:00Z"},{"value":16809,"date":"2022-08-01T05:00:00Z"},{"value":17571,"date":"2022-07-31T05:00:00Z"},{"value":23907,"date":"2022-07-30T05:00:00Z"},{"value":39007,"date":"2022-07-29T05:00:00Z"},{"value":38823,"date":"2022-07-28T05:00:00Z"}]}

My current solution is this:

var = sampleStr[78] + sampleStr[79] + sampleStr[80]

It works for the current string but if the recentAveragePrice was above 999 it would stop working and i was wondering if instead of getting a fixed number i could search for it inside the string.

Please share the full code you have tried with, otherwise we'll just be guessing. — Cow, Aug 11 '22 at 11:18
Are you certain on dealing with a string rather than a dictionary? — Jobo Fernandez, Aug 11 '22 at 11:21
Im having issues sharing the code but its in this replit page https://replit.com/@ShyMike/8-Bit-Collection-Profit#main.py — ShyMike, Aug 11 '22 at 11:21
I recommend that you look at the *requests* module and, in particular, the json() function that's available in a requests.get() response object. That will give you a dictionary which will allow you straightforward access to the relevant key. Top tip: Don't try to process JSON as a string. Convert to a Python dictionary first. Rewrite as JSON if necessary — DarkKnight, Aug 11 '22 at 11:39

score 1 · Answer 1 · answered Aug 11 '22 at 11:19

Since this is json you should just be able to parse it and access recentAveragePrice:

import json
sample_string = '''{"assetStock":null,"sales":250694,"numberRemaining":null,"recentAveragePrice":731,"originalPrice":null,"priceDataPoints":[{"value":661,"date":"2022-08-11T05:00:00Z"},{"value":592,"date":"2022-08-10T05:00:00Z"},{"value":443,"date":"2022-08-09T05:00:00Z"}],"volumeDataPoints":[{"value":155,"date":"2022-08-11T05:00:00Z"},{"value":4595,"date":"2022-08-10T05:00:00Z"},{"value":12675,"date":"2022-08-09T05:00:00Z"},{"value":22179,"date":"2022-08-08T05:00:00Z"},{"value":15181,"date":"2022-08-07T05:00:00Z"},{"value":14541,"date":"2022-08-06T05:00:00Z"},{"value":15310,"date":"2022-08-05T05:00:00Z"},{"value":14146,"date":"2022-08-04T05:00:00Z"},{"value":13083,"date":"2022-08-03T05:00:00Z"},{"value":14460,"date":"2022-08-02T05:00:00Z"},{"value":16809,"date":"2022-08-01T05:00:00Z"},{"value":17571,"date":"2022-07-31T05:00:00Z"},{"value":23907,"date":"2022-07-30T05:00:00Z"},{"value":39007,"date":"2022-07-29T05:00:00Z"},{"value":38823,"date":"2022-07-28T05:00:00Z"}]}'''

data = json.loads(sample_string)
recent_price = data['recentAveragePrice']
print(recent_price)

outputs:

score 1 · Accepted Answer · answered Aug 11 '22 at 11:43

Your replit code shows that you're acquiring JSON data from some website. Here's an example based on the URL that you're using. It shows how you check the response status, acquire the JSON data as a Python dictionary then print a value associated with a particular key. If the key is missing, it will print None:

import requests

(r := requests.get('https://economy.roblox.com/v1/assets/10159617728/resale-data')).raise_for_status()

jdata = r.json()

print(jdata.get('recentAveragePrice'))

Output:

score 0 · Answer 3 · answered Aug 11 '22 at 11:34

Your data is in a popular format called JSON (JavaScript Object Notation). It's commonly used to exchange data between different systems like a server and a client, or a Python program and JavaScript program.

Now Python doesn't use JSON per-se, but it has a data type called a dictionary that behaves very similarly to JSON. You can access elements of a dictionary as simply as:

print(my_dictionary["recentAveragePrice"])

Python has a built-in library meant specifically to handle JSON data, and it includes a function called loads() that can convert a string into a Python dictionary. We'll use that.

Finally, putting all that together, here is a more robust program to help parse your string and pick out the data you need. Dictionaries can do a lot more cool stuff, so make sure you take a look at the links above.

# import the JSON library
# specifically, we import the `loads()` function, which will convert a JSON string into a Python object
from json import loads

# let's store your string in a variable
original_string = """
{"assetStock":null,"sales":250694,"numberRemaining":null,"recentAveragePrice":731,"originalPrice":null,"priceDataPoints":[{"value":661,"date":"2022-08-11T05:00:00Z"},{"value":592,"date":"2022-08-10T05:00:00Z"},{"value":443,"date":"2022-08-09T05:00:00Z"}],"volumeDataPoints":[{"value":155,"date":"2022-08-11T05:00:00Z"},{"value":4595,"date":"2022-08-10T05:00:00Z"},{"value":12675,"date":"2022-08-09T05:00:00Z"},{"value":22179,"date":"2022-08-08T05:00:00Z"},{"value":15181,"date":"2022-08-07T05:00:00Z"},{"value":14541,"date":"2022-08-06T05:00:00Z"},{"value":15310,"date":"2022-08-05T05:00:00Z"},{"value":14146,"date":"2022-08-04T05:00:00Z"},{"value":13083,"date":"2022-08-03T05:00:00Z"},{"value":14460,"date":"2022-08-02T05:00:00Z"},{"value":16809,"date":"2022-08-01T05:00:00Z"},{"value":17571,"date":"2022-07-31T05:00:00Z"},{"value":23907,"date":"2022-07-30T05:00:00Z"},{"value":39007,"date":"2022-07-29T05:00:00Z"},{"value":38823,"date":"2022-07-28T05:00:00Z"}]}
"""

# convert the string into a dictionary object
dictionary_object = loads(original_string)

# access the element you need
print(dictionary_object["recentAveragePrice"])

Output upon running this program:

$ python exp.py 
731

Is there a way to search for a string and copy text in front until it reaches a comma?

3 Answers3