How to merge multiple json files into one file in python

Question

I want to merge multiple json files into one file in python. The thing that I want to do is if there are several .json files like:

# temp1.json
[{'num':'1', 'item':'smartphone','data':'2019-01-01'},
{'num':'2', 'item':'smartphone','data':'2019-01-02'},
{'num':'3', 'item':'smartphone','data':'2019-01-03'},
{'num':'4', 'item':'smartphone','data':'2019-01-04'}]

# temp2.json
[{'num':'5', 'item':'smartphone','data':'2019-01-05'},
{'num':'6', 'item':'smartphone','data':'2019-01-06'},
{'num':'7', 'item':'smartphone','data':'2019-01-07'}]

# temp3.json
[{'num':'8', 'item':'smartphone','data':'2019-01-08'},
{'num':'9', 'item':'smartphone','data':'2019-01-09'},
{'num':'10', 'item':'smartphone','data':'2019-01-10'},
{'num':'11', 'item':'smartphone','data':'2019-01-11'},
{'num':'12', 'item':'smartphone','data':'2019-01-12'}]

The result.json files I want to get should look like:

# result.json
[{'num':'1', 'item':'smartphone','data':'2019-01-01'},
{'num':'2', 'item':'smartphone','data':'2019-01-02'},
{'num':'3', 'item':'smartphone','data':'2019-01-03'},
{'num':'4', 'item':'smartphone','data':'2019-01-04'},
{'num':'5', 'item':'smartphone','data':'2019-01-05'},
{'num':'6', 'item':'smartphone','data':'2019-01-06'},
{'num':'7', 'item':'smartphone','data':'2019-01-07'},
{'num':'8', 'item':'smartphone','data':'2019-01-08'},
{'num':'9', 'item':'smartphone','data':'2019-01-09'},
{'num':'10', 'item':'smartphone','data':'2019-01-10'},
{'num':'11', 'item':'smartphone','data':'2019-01-11'},
{'num':'12', 'item':'smartphone','data':'2019-01-12'}]

The result.json files I got is:

# result.json
[[{'num':'1', 'item':'smartphone','data':'2019-01-01'},
{'num':'2', 'item':'smartphone','data':'2019-01-02'},
{'num':'3', 'item':'smartphone','data':'2019-01-03'},
{'num':'4', 'item':'smartphone','data':'2019-01-04'}],
[{'num':'5', 'item':'smartphone','data':'2019-01-05'},
{'num':'6', 'item':'smartphone','data':'2019-01-06'},
{'num':'7', 'item':'smartphone','data':'2019-01-07'}],
[{'num':'8', 'item':'smartphone','data':'2019-01-08'},
{'num':'9', 'item':'smartphone','data':'2019-01-09'},
{'num':'10', 'item':'smartphone','data':'2019-01-10'},
{'num':'11', 'item':'smartphone','data':'2019-01-11'},
{'num':'12', 'item':'smartphone','data':'2019-01-12'}]]

I used the code to merge .json files from here and changed it very slightly like below:

files=['my.json','files.json',...,'name.json']

def merge_JsonFiles(filename):
    result = list()
    for f1 in filename:
        with open(f1, 'r') as infile:
            result.append(json.load(infile))

    with open('counseling3.json', 'w') as output_file:
        json.dump(result, output_file)

merge_JsonFiles(files)

I already read several related questions, but there is no answer I need. Can anyone help me?

Answer 1

You should use extend instead of append. It will add the items of the passed list to result instead of a new list:

files=['my.json','files.json',...,'name.json']

def merge_JsonFiles(filename):
    result = list()
    for f1 in filename:
        with open(f1, 'r') as infile:
            result.extend(json.load(infile))

    with open('counseling3.json', 'w') as output_file:
        json.dump(result, output_file)

merge_JsonFiles(files)

Answer 2

import json
import pandas as pd

with open('example1.json') as f1:               # open the file
    data1 = json.load(f1)

with open('example2.json') as f2:                # open the file       
    data2 = json.load(f2)
    
df1 = pd.DataFrame([data1])                      # Creating DataFrames
df2 = pd.DataFrame([data2])                      # Creating DataFrames

MergeJson = pd.concat([df1, df2], axis=1)         # Concat DataFrames

MergeJson.to_json("MergeJsonDemo.json")          # Writing Json

Answer 3

files=['my.json','files.json',...,'name.json']

with open('merged_file_name.json', "w") as outfile:
   outfile.write('{}'.format('\n'.join([open(f, "r").read() for f in files])))