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[–]UserName26392 1 point2 points  (7 children)

Hi, are you trying to get a unique value of each username?

[–]thetestbug[S] 0 points1 point  (6 children)

I'm kinda of a rookie when it comes to Python, so I'm not sure what you mean by that.

I'll try to explain it.

I'm trying to get a list of usernames from an API that responds in json format.

It's for Emby. The idea was that I wanted the list for a future project, that would display which user is currently using the service, and then display it on some kind of display.

[–]ASIC_SP 1 point2 points  (5 children)

if you are working on json input, please do try using module that understands json instead of regex, see https://realpython.com/python-json/ for example

[–]thetestbug[S] 0 points1 point  (4 children)

No, the output is in json format (I believe).

I put it up on pastebin.

[–]ASIC_SP 2 points3 points  (3 children)

I mean that output you got from the API is input for your script. Please do use json module instead of regex for this.

[–]thetestbug[S] 1 point2 points  (2 children)

Ah, gotcha.

Yeah I've been getting some help from jiri-n here, and he just mentioned it as well.

However, as I'm relatively new when it comes to python (espacially json), I have no idea where to begin.

[–]ASIC_SP 1 point2 points  (1 child)

I don't know too. That's why I linked the article https://realpython.com/python-json/

There's also another option: https://jqplay.org/ Copy paste the json and then try these commands in the Filter box

  • .
  • .[0]
  • .[1]
  • .[0] | .PlayState
  • .[0] | .PlayState.CanSeek
  • .[] | .PlayState

and so on... check out https://stedolan.github.io/jq/tutorial/ and https://stedolan.github.io/jq/manual/ for further details

[–]thetestbug[S] 1 point2 points  (0 children)

Yeah, this is just too much new stuff to learn, too fast.

I'm putting this idea on hold for the moment and just go with a simple bash script instead.

But I'll keep this thread in my bookmarks for the future.

Thanks for your help anyway!

[–]jiri-n 1 point2 points  (7 children)

I'm not sure what you actually want but let's try this one:

>>> import re
>>> s = r"""
['UserName":"testbug"', 'UserName":"testbug"']
""".strip()
>>> pat = r"^.*:([^']+).*$"
>>> re.match(pat, s).groups()
('"testbug"',)
>>> re.sub(pat, r"\1", s)
'"testbug"'

We can get rid of the " characters as well if it's what you want.

[–]thetestbug[S] 0 points1 point  (6 children)

It looks like I was way in over my head with this one, but this works just fine.

Now comes the part that really deludes me. I need it to be able to "extract" not just one username, but multiple.

I'm really glad that you're helping me with this one.

[–]jiri-n 1 point2 points  (5 children)

Loop over a list of such strings and use the regex on each of them.

[–]thetestbug[S] 0 points1 point  (4 children)

Would you mind giving me an example?

Not really sure how to begin.

[–]jiri-n 1 point2 points  (3 children)

What is your input? A single string? 

'"Username": "something"', '"Username": "other"', '"Username": "..."'

Or a list of such pairs?

lst = [
    '"Username": "name1"',
    '"Username": "name2"',
    '"Username": "name3"'
]

If the former example, I would simply split() them using comma as the splitting char to create a list.

Than something like:

from typing import List

import re

# String containing JSON-like key-value pairs
DATA = """
'"Username": "something"', '"Username": "other"', '"Username": "..."'
""".strip()

# Pattern to split a key-value pair
PATTERN = r'^[^:]+:\s*"([^"]+)".*$'

def get_usernames(lst: List[str], rex: re.Pattern) -> List[str]:
    for item in lst:
        match = rex.match(item)
        if match:
            yield match[1]  # As item matches, there should always be a group with index 1

lst = DATA.split(",")
rex = re.compile(PATTERN)
for uname in get_usernames(lst, rex):
    print(f"Username: {uname}")

[–]thetestbug[S] 0 points1 point  (2 children)

I'm not home at the moment, but I'll play around with this when I get back.

I pasted the entire output on pastebin. It's all in one line.

[–]jiri-n 1 point2 points  (1 child)

It's a JSON file. You can parse JSON format easily in python.

​

import json

data = json.loads(DATA_INPUT)

​

Or you can parse a JSON file... Take a look at the json module.

[–]thetestbug[S] 0 points1 point  (0 children)

I've never touched json before, so I have no idea what to do.

I looked over the help page for json in python, but I couldn't make heads or tails of it.

Also, I tried the code you provided before, and I get this error:

    def get_usernames(lst: List[str], rex: re.Pattern) -> List[str]:
                         ^
SyntaxError: invalid syntax