How to dump data into Json file
*as can see in the below python code I am trying the dump data in Json file so but I am struggling to do it in python code *
import time
import json
import os
def long_function(name):
cache_path = 'cache.json'
if not os.path.isfile(cache_path):
with open(cache_path, 't') as json_file:
cache_file_data = [name]
jsondump(cache_file_data, json_file)
else:
with open(cache_path, 'r') as json_file:
cache_file_data = json.load(json_file)
if name in cache_file_data:
print("Name already exist")
return name
else:
cache_file_data.append(name)
for e in range(5):
time.sleep(1)
print(e+1)
with open(cache_path, 'w') as json_file:
jsondump(cache_file_data, json_file)
print("New Name added in cache")
return name
print(long_function('nitu'))
so please resolve my problem......please help me
import json
# JSON data:
x = '{ "organization":"New_holn",
"city":"Noida",
"country":"India"}'
# python object to be appended
y = {"pin":117845}
# parsing JSON string:
z = json.loads(x)
# appending the data
z.update(y)
# the result is a JSON string:
print(json.dumps(z))
This is nothing but follow this pattern and your so your code error is ..you are not defined file mode correctly in if condition
with open (cache_path. "t") as json_file:
Instead of
with open (cache_path. "w") as json_file:
And second thing is you are not doing dump data
I am currently using the following code to convert a large CSV file to a JSON file.
import csv
import json
def csv_to_json(csvFilePath, jsonFilePath):
jsonArray = []
with open(csvFilePath, encoding='utf-8') as csvf:
csvReader = csv.DictReader(csvf)
for row in csvReader:
jsonArray.append(row)
with open(jsonFilePath, 'w', encoding='utf-8') as jsonf:
jsonString = json.dumps(jsonArray, indent=4)
jsonf.write(jsonString)
csvFilePath = r'test_data.csv'
jsonFilePath = r'test_data.json'
csv_to_json(csvFilePath, jsonFilePath)
This code works fine and I am able to convert the CSV to JSON without any issues. However, as the CSV file contains 600,000+ rows and hence as many items in my JSON, it has become very difficult to manage the JSON file.
I would like to modify my above code such that for every 5000 rows of the CSV, the data is written into a new JSON file. Ideally, I would be having 120 (600,000/5000) JSON files in this case.
How can I do the same?
Split up your read\write methods and add a simple threshold:
JSON_ENTRIES_THRESHOLD = 5000 # modify to whatever you see suitable
def write_json(json_array, filename):
with open(filename, 'w', encoding='utf-8') as jsonf:
json.dump(json_array, jsonf) # note the usage of .dump directly to a file descriptor
def csv_to_json(csvFilePath, jsonFilePath):
jsonArray = []
with open(csvFilePath, encoding='utf-8') as csvf:
csvReader = csv.DictReader(csvf)
filename_index = 0
for row in csvReader:
jsonArray.append(row)
if len(jsonArray) >= JSON_ENTRIES_THRESHOLD:
# if we reached the treshold, write out
write_json(jsonArray, f"jsonFilePath-{filename_index}.json")
filename_index += 1
jsonArray = []
# Finally, write out the remainder
write_json(jsonArray, f"jsonFilePath-{filename_index}.json")
I'm attempting to convert yelps data set that is in JSON to a csv format. The new csv file that is created is empty.
I've tried different ways to iterate through the JSON but they all give me a zero bytes file.
The json file looks like this:
{"business_id":"1SWheh84yJXfytovILXOAQ","name":"Arizona Biltmore Golf Club","address":"2818 E Camino Acequia Drive","city":"Phoenix","state":"AZ","postal_code":"85016","latitude":33.5221425,"longitude":-112.0184807,"stars":3.0,"review_count":5,"is_open":0,"attributes":{"GoodForKids":"False"},"categories":"Golf, Active Life","hours":null}
import json
import csv
infile = open("business.json","r")
outfile = open("business2.csv","w")
data = json.load(infile)
infile.close()
out = csv.writer(outfile)
out.writerow(data[0].keys())
for row in data:
out.writerow(row.values())
I get an "extra data" message when the code runs. The new business2 csv file is empty and the size is zero bytes.
if you JSON has only one row.. then try this
infile = open("business.json","r")
outfile = open("business2.csv","w")
data = json.load(infile)
infile.close()
out = csv.writer(outfile)
#print(data.keys())
out.writerow(data.keys())
out.writerow(data.values())
Hi Please try the below code, by using with command the file access will automatically get closed when the control moves out of scope of with
infile = open("business.json","r")
outfile = open("business2.csv","w")
data = json.load(infile)
infile.close()
headers = list(data.keys())
values = list(data.values())
with open("business2.csv","w") as outfile:
out = csv.writer(outfile)
out.writerow(headers)
out.writerow(values)
You need to use with to close file.
import json
import csv
infile = open("business.json","r")
data = json.load(infile)
infile.close()
with open("business2.csv","w") as outfile:
out = csv.writer(outfile)
out.writerow(list(data.keys()))
out.writerow(list(data.values()))
Here's my code, really simple stuff...
import csv
import json
csvfile = open('file.csv', 'r')
jsonfile = open('file.json', 'w')
fieldnames = ("FirstName","LastName","IDNumber","Message")
reader = csv.DictReader( csvfile, fieldnames)
out = json.dumps( [ row for row in reader ] )
jsonfile.write(out)
Declare some field names, the reader uses CSV to read the file, and the filed names to dump the file to a JSON format. Here's the problem...
Each record in the CSV file is on a different row. I want the JSON output to be the same way. The problem is it dumps it all on one giant, long line.
I've tried using something like for line in csvfile: and then running my code below that with reader = csv.DictReader( line, fieldnames) which loops through each line, but it does the entire file on one line, then loops through the entire file on another line... continues until it runs out of lines.
Any suggestions for correcting this?
Edit: To clarify, currently I have: (every record on line 1)
[{"FirstName":"John","LastName":"Doe","IDNumber":"123","Message":"None"},{"FirstName":"George","LastName":"Washington","IDNumber":"001","Message":"Something"}]
What I'm looking for: (2 records on 2 lines)
{"FirstName":"John","LastName":"Doe","IDNumber":"123","Message":"None"}
{"FirstName":"George","LastName":"Washington","IDNumber":"001","Message":"Something"}
Not each individual field indented/on a separate line, but each record on it's own line.
Some sample input.
"John","Doe","001","Message1"
"George","Washington","002","Message2"
The problem with your desired output is that it is not valid json document,; it's a stream of json documents!
That's okay, if its what you need, but that means that for each document you want in your output, you'll have to call json.dumps.
Since the newline you want separating your documents is not contained in those documents, you're on the hook for supplying it yourself. So we just need to pull the loop out of the call to json.dump and interpose newlines for each document written.
import csv
import json
csvfile = open('file.csv', 'r')
jsonfile = open('file.json', 'w')
fieldnames = ("FirstName","LastName","IDNumber","Message")
reader = csv.DictReader( csvfile, fieldnames)
for row in reader:
json.dump(row, jsonfile)
jsonfile.write('\n')
You can use Pandas DataFrame to achieve this, with the following Example:
import pandas as pd
csv_file = pd.DataFrame(pd.read_csv("path/to/file.csv", sep = ",", header = 0, index_col = False))
csv_file.to_json("/path/to/new/file.json", orient = "records", date_format = "epoch", double_precision = 10, force_ascii = True, date_unit = "ms", default_handler = None)
import csv
import json
file = 'csv_file_name.csv'
json_file = 'output_file_name.json'
#Read CSV File
def read_CSV(file, json_file):
csv_rows = []
with open(file) as csvfile:
reader = csv.DictReader(csvfile)
field = reader.fieldnames
for row in reader:
csv_rows.extend([{field[i]:row[field[i]] for i in range(len(field))}])
convert_write_json(csv_rows, json_file)
#Convert csv data into json
def convert_write_json(data, json_file):
with open(json_file, "w") as f:
f.write(json.dumps(data, sort_keys=False, indent=4, separators=(',', ': '))) #for pretty
f.write(json.dumps(data))
read_CSV(file,json_file)
Documentation of json.dumps()
I took #SingleNegationElimination's response and simplified it into a three-liner that can be used in a pipeline:
import csv
import json
import sys
for row in csv.DictReader(sys.stdin):
json.dump(row, sys.stdout)
sys.stdout.write('\n')
You can try this
import csvmapper
# how does the object look
mapper = csvmapper.DictMapper([
[
{ 'name' : 'FirstName'},
{ 'name' : 'LastName' },
{ 'name' : 'IDNumber', 'type':'int' },
{ 'name' : 'Messages' }
]
])
# parser instance
parser = csvmapper.CSVParser('sample.csv', mapper)
# conversion service
converter = csvmapper.JSONConverter(parser)
print converter.doConvert(pretty=True)
Edit:
Simpler approach
import csvmapper
fields = ('FirstName', 'LastName', 'IDNumber', 'Messages')
parser = CSVParser('sample.csv', csvmapper.FieldMapper(fields))
converter = csvmapper.JSONConverter(parser)
print converter.doConvert(pretty=True)
I see this is old but I needed the code from SingleNegationElimination however I had issue with the data containing non utf-8 characters. These appeared in fields I was not overly concerned with so I chose to ignore them. However that took some effort. I am new to python so with some trial and error I got it to work. The code is a copy of SingleNegationElimination with the extra handling of utf-8. I tried to do it with https://docs.python.org/2.7/library/csv.html but in the end gave up. The below code worked.
import csv, json
csvfile = open('file.csv', 'r')
jsonfile = open('file.json', 'w')
fieldnames = ("Scope","Comment","OOS Code","In RMF","Code","Status","Name","Sub Code","CAT","LOB","Description","Owner","Manager","Platform Owner")
reader = csv.DictReader(csvfile , fieldnames)
code = ''
for row in reader:
try:
print('+' + row['Code'])
for key in row:
row[key] = row[key].decode('utf-8', 'ignore').encode('utf-8')
json.dump(row, jsonfile)
jsonfile.write('\n')
except:
print('-' + row['Code'])
raise
Add the indent parameter to json.dumps
data = {'this': ['has', 'some', 'things'],
'in': {'it': 'with', 'some': 'more'}}
print(json.dumps(data, indent=4))
Also note that, you can simply use json.dump with the open jsonfile:
json.dump(data, jsonfile)
Use pandas and the json library:
import pandas as pd
import json
filepath = "inputfile.csv"
output_path = "outputfile.json"
df = pd.read_csv(filepath)
# Create a multiline json
json_list = json.loads(df.to_json(orient = "records"))
with open(output_path, 'w') as f:
for item in json_list:
f.write("%s\n" % item)
How about using Pandas to read the csv file into a DataFrame (pd.read_csv), then manipulating the columns if you want (dropping them or updating values) and finally converting the DataFrame back to JSON (pd.DataFrame.to_json).
Note: I haven't checked how efficient this will be but this is definitely one of the easiest ways to manipulate and convert a large csv to json.
As slight improvement to #MONTYHS answer, iterating through a tup of fieldnames:
import csv
import json
csvfilename = 'filename.csv'
jsonfilename = csvfilename.split('.')[0] + '.json'
csvfile = open(csvfilename, 'r')
jsonfile = open(jsonfilename, 'w')
reader = csv.DictReader(csvfile)
fieldnames = ('FirstName', 'LastName', 'IDNumber', 'Message')
output = []
for each in reader:
row = {}
for field in fieldnames:
row[field] = each[field]
output.append(row)
json.dump(output, jsonfile, indent=2, sort_keys=True)
def read():
noOfElem = 200 # no of data you want to import
csv_file_name = "hashtag_donaldtrump.csv" # csv file name
json_file_name = "hashtag_donaldtrump.json" # json file name
with open(csv_file_name, mode='r') as csv_file:
csv_reader = csv.DictReader(csv_file)
with open(json_file_name, 'w') as json_file:
i = 0
json_file.write("[")
for row in csv_reader:
i = i + 1
if i == noOfElem:
json_file.write("]")
return
json_file.write(json.dumps(row))
if i != noOfElem - 1:
json_file.write(",")
Change the above three parameter, everything will be done.
import csv
import json
csvfile = csv.DictReader('filename.csv', 'r'))
output =[]
for each in csvfile:
row ={}
row['FirstName'] = each['FirstName']
row['LastName'] = each['LastName']
row['IDNumber'] = each ['IDNumber']
row['Message'] = each['Message']
output.append(row)
json.dump(output,open('filename.json','w'),indent=4,sort_keys=False)