在python中匹配正则表达式并返回键

Question

I have a nested dictionary and I have a trouble matching a regular expression with values in dictionary. I need to iterate through values in dictionary and return a key where regex has matched in value.

I have nested dictionary like this:

    user_info = { 'user1': {'name': 'Aby',
                    'surname': 'Clark',
                    'description': 'Hi contact me by phone +1 548 5455 55 
                     or facebook.com/aby.clark'},
          'user2': {'name': 'Marta',
                     'surname': 'Bishop',
                     'description': 'Nice to meet you text me'},
           'user3': {'name': 'Janice',
                     'surname': 'Valinise',
                     'description': 'You can contact me by phone +1 457 
                      555667'},
           'user4': {'name': 'Helen',
                     'surname': 'Bush',
                     'description': 'You can contact me by phone +1 778 
                      65422'},
           'user5': {'name': 'Janice',
                     'surname': 'Valinise',
                     'description': 'You can contact me by phone +1 457 
                      5342327 or email janval@yahoo.com'}}

So I need to iterate through values of dictionary with regex and find a match and return back a key where is match happened.

A first problem I have faced is extracting a values from nested dictionary, but I solved this through:

   for key in user_info.keys():
       for values in user_info[key].values():
           print(values)

And this getting back a values from nested dictionary. So is there a way to iterate through this values with regex as it will find a match and return back a key where match is happened.

I tried the following:

 for key in user_info.keys():
     for values in user_info.[key].values():

         #this regex match the email
         email = re.compile(r'(^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+$)'.format(pattern), re.IGNORECASE|re.MULTILINE) 
         match = re.match(email)

         if match is not None:
             print ("No values.")

      if found: 
         return match

Am I doing something wrong? I am wrestling with this question for a week... Could you please tell me what's wrong and give a tips how to solve this #!4fd... please. Thank you!

PS And yep I didn't found the similar issue on stackoverflow and google. I've tried.

Answer 1

You can try using search instead of the match function in the next way:

for key in user_info.keys():
    for values in user_info[key].values():
        email = re.search(r'([a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+)+', values)
        if email != None:
            print(key)

This code will print all the keys with the matched inner value.

Notice that in the code you have tried you didn't use values at all.

Answer 2

Looks like you want to extract the emails from the JSON values while also returning the matched key. Here are 2 solutions. The first one is similar to yours and the second one is generalized to any JSON with arbitrary levels.

1. Two for loops

import re

user_info = {
  "user1": {
    "name": "Aby",
    "surname": "Clark",
    "description": "Hi contact me by phone +1 548 5455 55or facebook.com/aby.clark"
  },
  "user2": {
    "name": "Marta",
    "surname": "Bishop",
    "description": "Nice to meet you text me"
  },
  "user3": {
    "name": "Janice",
    "surname": "Valinise",
    "description": "You can contact me by phone +1 457 555667"
  },
  "user4": {
    "name": "Helen",
    "surname": "Bush",
    "description": "You can contact me by phone +1 778 65422"
  },
  "user5": {
    "name": "Janice",
    "surname": "Valinise",
    "description": "You can contact me by phone +1 457 5342327 or email janval@yahoo.com",
  }
}

matches = []
for user, info in user_info.items():
    for key, value in info.items():
        emails = re.findall("([a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+)", value)
        if emails:
          matches.append((f'{user}.{key}', emails))

print(matches)
# -> [('user5.description', ['janval@yahoo.com'])]

2. The recursive approach for arbitrary JSON

import re

user_info = {
  "user1": {
    "name": "Aby",
    "surname": "Clark",
    "description": "Hi contact me by phone +1 548 5455 55or janval@yahoo.com",
    "friends": [
      {
        "name": "Aby",
        "surname": "Clark",
        "description": "Hi contact me by phone +1 548 5455 55or janval@yahoo.com",
      }
    ]
  }
}

def traverse(obj, keys = []):
  if isinstance(obj, str):
    emails = re.findall("([a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+)", obj)
    return [('.'.join(keys), emails)] if emails else []
  if isinstance(obj, dict):
    return [match for key, value in obj.items() for match in traverse(value, [*keys, key])]
  if isinstance(obj, list):
    return [match for i, value in enumerate(obj) for match in traverse(value, [*keys, str(i)])] 
  return []

print(traverse(user_info, []))
# -> [('user1.description', ['janval@yahoo.com']), ('user1.friends.0.description', ['janval@yahoo.com'])]