Python program to convert URL Parameters to Dictionary items

Given URL Parameters string, convert to dictionary items.

Input : test_str = ‘gfg=4&is=5’ 
Output : {‘gfg’: [‘4’], ‘is’: [‘5’]} 
Explanation : gfg’s value is 4.

Input : test_str = ‘gfg=4’ 
Output : {‘gfg’: [‘4’]} 
Explanation : gfg’s value is 4 as param. 

Method #1 : Using urllib.parse.parse_qs()

This is default inbuilt function which performs this task, it parses and the keys are formed from LHS of “=” and return list of values that are in RHS values for the parameters. Thus, import external urllib.parse(), to enable this to work.

Python3

# import module
import urllib.parse

# initializing string
test_str = 'gfg=4&is=5&best=yes'

# printing original string
print("The original string is : " + str(test_str))

# parse_qs gets the Dictionary and value list
res = urllib.parse.parse_qs(test_str)

# printing result
print("The parsed URL Params : " + str(res))

OutputThe original string is : gfg=4&is=5&best=yes The parsed URL Params : {‘gfg’: [‘4’], ‘is’: [‘5’], ‘best’: [‘yes’]}

Method #2 : Using findall() + setdefault()

In this, we get all the parameters using findall(), and then assign keys and values using setdefault() and loop.

Python3

import re

# initializing string
test_str = 'gfg=4&is=5&best=yes'

# printing original string
print("The original string is : " + str(test_str))

# getting all params
params = re.findall(r'([^=&]+)=([^=&]+)', test_str)

# assigning keys with values
res = dict()
for key, val in params:

    res.setdefault(key, []).append(val)

# printing result
print("The parsed URL Params : " + str(res))

OutputThe original string is : gfg=4&is=5&best=yes The parsed URL Params : {‘gfg’: [‘4’], ‘is’: [‘5’], ‘best’: [‘yes’]}

Method #3 : Using split()

Python3

#python program to convert
#URL parameters to dictionary items
# initializing string
test_str = 'gfg=4&is=5&best=yes'

# printing original string
print("The original string is : " + str(test_str))

# getting all params
res = dict()
x=test_str.split("&")
for i in x:
    a,b=i.split("=")
    # assigning keys with values
    res[a]=[b]
# printing result
print("The parsed URL Params : " + str(res))

Output

The original string is : gfg=4&is=5&best=yes
The parsed URL Params : {'gfg': ['4'], 'is': ['5'], 'best': ['yes']}

Method #4 : Using setdefault()

Approach

Using dictionary.setdefault() method

Algorithm

1. Split the input string into a list of key-value pairs using the split() method with the ‘&’ delimiter.
2. Create an empty dictionary to store the key-value pairs.
3. Iterate over the list of key-value pairs and split each item on the basis of ‘=’.
4. Add the key-value pairs to the dictionary using the setdefault() method. If the key does not exist, create a new key in the dictionary and initialize its value to an empty list. Then, append the value to this list.

Python3

# Python program to convert URL Parameters to Dictionary items

test_str = 'gfg=4&is=5'

# split the string on the basis of '&' and create a list of key-value pairs
temp_list = test_str.split('&')

# create an empty dictionary
res_dict = {}

# iterate over the key-value pairs and add them to the dictionary
for item in temp_list:
    key, val = item.split('=')  # split each item of the list on the basis of '='
    res_dict.setdefault(key, []).append(val)  # add key-value pair to dictionary

print(res_dict)

Output

{'gfg': ['4'], 'is': ['5']}

Time complexity: O(N) depends on the length of the input string and the number of key-value pairs in it. The split() method and the setdefault() method take linear time in the number of key-value pairs. where N is the number of key-value pairs in the input string.

Auxiliary Space: O(N),  depends on the number of key-value pairs in the input string. We create a dictionary to store the key-value pairs, and each key can have a list of values. where N is the number of key-value pairs in the input string.