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Append to a json array multiple times in Python

I want to write a code in python to create a sample JSON file in a by duplicating the objects 'array' object x number of times to create a large file with the required format using an existing smaller JSON file.
smaller JSON sample file:
{"item":"book1","price":"10.00","array"[{"object1":"var1","object2":"var2"}]}
output file:
{"item":"book1","price":"10.00","array"[{"object1":"var1","object2":"var2"},{"object1":"var1","object2":"var2"},{"object1":"var1","object2":"var2"},......]}
I have tried this but I can figure out how to just duplicate the objects in the array:
result = ''
x = 2
with open("test.json", "r") as infile:
for i in range(x):
infile.seek(0)
result += infile.read() + ','
with open("merged.json", "w") as outfile:
outfile.writelines(result)
which gives me this:
{"item":"book1","price":"10.00","array"[{"object1":"var1","object2":"var2"}]},{"item":"book1","price":"10.00","array"[{"object1":"var1","object2":"var2"}]}

You can use json and do something like this.
import json
myfile='test.json'
with open(myfile) as jfile:
data=json.loads(jfile.read())
x=5 #x can be how many duplicates you want to make
data['array']=data['array']*x
with open(myfile,'w') as jfile:
json.dumps(data,jfile)

Using values from .txt file in python code

I'm kinda lost on how to use constant values from an external .txt file in my python file
File.txt:
email=value1
phone=value2
name=value3
And I want to use these values on my python file.
I have tried to do this:
Data = open('file.txt', 'r')
data1= Data.read(email)
print(data1)
But it isn't working as expected, expected output is "Value1". But I get an error, and if I only do Data.read() I am getting:
email=value1
phone=value2
name=value3
How would I get each value separately to use them in my python code?

I'm not sure exactly what are you looking for, but here's something that might help you:
# Open the file for read
Data = open('file.txt', 'r')
# Reading the data from file
data1 = {}
for line in Data.readlines():
key, val = line.strip().split("=") # strip() removes "\n" at the end of each line
data1[key] = val # Placing key,val in dictionary
# Using the data
email = data1['email']
# Don't forget to close the file
Data.close()

Try this:
with open('file.txt', 'r') as file:
data1 = dict(zip([i.strip().split('=') for i in file.readlines() if i]))
print(data1['email'])
Output:
value1

Extracted from #U12-Forward, working and tried to describe what we are doing:
with open('test.txt', 'r') as f:
data = dict([i.split('=') for i in f.read().splitlines()])
print(data["email"]) # value1
print(data['phone']) # value2
What we are doing is, using f.read() reading file and splitting the f.read() into list from linebreak(\n) and looping through that list and again splitting those each lines with = and making list and then at last dict.
If it is harder for you to understand then you can split these lines like this, made easier to understand:
with open('test.txt', 'r') as f:
read=f.read()
data={}
for i in read.splitlines():
x=i.split("=")
data.update(dict([x]))
print(data["email"]) # value1
print(data['phone']) # value2
Additionally:
You can use,change and do anything after this:
data["email"]="test#.."
print(data["email"]) # test#..
email=data["email"]
# Now you can use this email variable as your python variable.

How to parse dictionary syntaxed string to dictionary object

I have a file syntaxed in a way that ressembles a Dictionary as follows:
{YEARS:5}
{GROUPS:[1,2]}
{SAVE_FILE:{USE:1,NAME:CustomCalendar.ics}}
{SAVE_ONLINE:{USE:1,NAME:Custom Calendar,EMAIL:an.email#something.com,PASSWORD:AcompLExP#ssw0rd}}
{COURSES:[BTC,CIT,CQN,OSA,PRJCQN,PRJIOT,PILS,SPO,SHS1]}
I would like to find a way to parse each individual line into a dictionary as it is written. The difficulty I have is that some of these lines contain a dictionary as their value.
I am capable of taking the single lines and converting them to actual dictionaries but I am having an issue when working with the other lines.
Here is the code I have so far:
def get_config(filename=):
with open(filename, encoding="utf8") as config:
years = config.read().split()[0]
print(parse_line(years))
def parse_line(input_line):
input_line = input_line.strip("{}")
input_line = input_line.split(":")
return {input_line[i]: input_line[i + 1] for i in range(0, len(input_line), 2)}
If at all possible, I'd love to be able to deal with any line within a single function and hopefully deal with more than two nested dictionaries.
Thanks in advance!

If your file would contain valid JSON format, it would be an easy task to read the file and convert your data structures to dictionaries.
To give an example, consider having the following line of text in a file text.txt:
{"SAVE_ONLINE":{"USE":1,"NAME":"Custom Calendar","EMAIL":"an.email#something.com","PASSWORD":"AcompLExP#ssw0rd"}}
Please note, that the only difference are the quotes " around strings.
You can easily parse the line to a dictionary structure with:
import json
with open('text.txt', 'r') as f:
d = json.loads(f.read())
Output
print(d)
# {'SAVE_ONLINE': {'USE': 1, 'NAME': 'Custom Calendar', 'EMAIL': 'an.email#something.com', 'PASSWORD': 'AcompLExP#ssw0rd'}}

Accessing items in a dump of dictionary objects in Python

I have a strange dataset from our customer. It is a .json file but inside it looks like below
{"a":"aaa","b":"bbb","text":"hello"}
{"a":"aaa","b":"bbb","text":"hi"}
{"a":"aaa","b":"bbb","text":"hihi"}
As you notice, this is just a dump of dictionary objects. It is neither a list (no [] and comma seperator between objects) nor a proper JSON although the file extension is .json. So I am really confused about how to read this file.
All I care about is reading all the text keys from each of the dictionary objects.

This "strange dataset" is actually an existing format that builds upon JSON, called JSONL.
As #user655321 said, you can parse each line. Here's a more complete example with the complete dataset available in the list of dicts dataset:
import json
dataset = []
with open("my_file.json") as file:
for line in file:
dataset.append(json.loads(line))

In [51]: [json.loads(i)["text"] for i in open("file.json").readlines()]
Out[51]: ['hello', 'hi', 'hihi']
Use list comprehension, it's easier

You can read it line by line and convert the lines to JSON objects and extract the needed data text in your case.
You can do something as follows:
import json
lines = open("file.txt").readlines()
for line in lines:
dictionary = json.loads(line)
print(dictionary["text"])

Since it's not a single JSON file, you can read in the input line by line and deserialize them independently:
import json
with open('my_file.json') as fh:
for line in fh:
json_obj = json.loads(line)
keys = json_obj.keys() # eg, 'a', 'b', 'text'
text_val = json_obj['text'] # eg, 'hello', 'hi', or 'hihi'

How about splitting the content by \n then using json to load each dictionary? something like:
import json
with open(your_file) as f:
data = f.read()
my_dicts = []
for line in data.split():
my_dicts.append(json.loads(line))

import ast
with open('my_file.json') as fh:
for line in fh:
try:
dict_data = ast.literal_eval(line)
assert isinstance(dict_data,dict)
### Process Dictionary Data here or append to list to convert to list of dicts
except (SyntaxError, ValueError, AssertionError):
print('ERROR - {} is not a dictionary'.format(line))

How to set Chrome flags using terminal in Mac? [duplicate]

I'm trying to create a function that would add entries to a json file. Eventually, I want a file that looks like
[{"name" = "name1", "url" = "url1"}, {"name" = "name2", "url" = "url2"}]
etc. This is what I have:
def add(args):
with open(DATA_FILENAME, mode='r', encoding='utf-8') as feedsjson:
feeds = json.load(feedsjson)
with open(DATA_FILENAME, mode='w', encoding='utf-8') as feedsjson:
entry = {}
entry['name'] = args.name
entry['url'] = args.url
json.dump(entry, feedsjson)
This does create an entry such as {"name"="some name", "url"="some url"}. But, if I use this add function again, with different name and url, the first one gets overwritten. What do I need to do to get a second (third...) entry appended to the first one?
EDIT: The first answers and comments to this question have pointed out the obvious fact that I am not using feeds in the write block. I don't see how to do that, though. For example, the following apparently will not do:
with open(DATA_FILENAME, mode='a+', encoding='utf-8') as feedsjson:
feeds = json.load(feedsjson)
entry = {}
entry['name'] = args.name
entry['url'] = args.url
json.dump(entry, feeds)

json might not be the best choice for on-disk formats; The trouble it has with appending data is a good example of why this might be. Specifically, json objects have a syntax that means the whole object must be read and parsed in order to understand any part of it.
Fortunately, there are lots of other options. A particularly simple one is CSV; which is supported well by python's standard library. The biggest downside is that it only works well for text; it requires additional action on the part of the programmer to convert the values to numbers or other formats, if needed.
Another option which does not have this limitation is to use a sqlite database, which also has built-in support in python. This would probably be a bigger departure from the code you already have, but it more naturally supports the 'modify a little bit' model you are apparently trying to build.

You probably want to use a JSON list instead of a dictionary as the toplevel element.
So, initialize the file with an empty list:
with open(DATA_FILENAME, mode='w', encoding='utf-8') as f:
json.dump([], f)
Then, you can append new entries to this list:
with open(DATA_FILENAME, mode='w', encoding='utf-8') as feedsjson:
entry = {'name': args.name, 'url': args.url}
feeds.append(entry)
json.dump(feeds, feedsjson)
Note that this will be slow to execute because you will rewrite the full contents of the file every time you call add. If you are calling it in a loop, consider adding all the feeds to a list in advance, then writing the list out in one go.

Append entry to the file contents if file exists, otherwise append the entry to an empty list and write in in the file:
a = []
if not os.path.isfile(fname):
a.append(entry)
with open(fname, mode='w') as f:
f.write(json.dumps(a, indent=2))
else:
with open(fname) as feedsjson:
feeds = json.load(feedsjson)
feeds.append(entry)
with open(fname, mode='w') as f:
f.write(json.dumps(feeds, indent=2))

Using a instead of w should let you update the file instead of creating a new one/overwriting everything in the existing file.
See this answer for a difference in the modes.

One possible solution is do the concatenation manually, here is some useful
code:
import json
def append_to_json(_dict,path):
with open(path, 'ab+') as f:
f.seek(0,2) #Go to the end of file
if f.tell() == 0 : #Check if file is empty
f.write(json.dumps([_dict]).encode()) #If empty, write an array
else :
f.seek(-1,2)
f.truncate() #Remove the last character, open the array
f.write(' , '.encode()) #Write the separator
f.write(json.dumps(_dict).encode()) #Dump the dictionary
f.write(']'.encode()) #Close the array
You should be careful when editing the file outside the script not add any spacing at the end.

this, work for me :
with open('file.json', 'a') as outfile:
outfile.write(json.dumps(data))
outfile.write(",")
outfile.close()

I have some code which is similar, but does not rewrite the entire contents each time. This is meant to run periodically and append a JSON entry at the end of an array.
If the file doesn't exist yet, it creates it and dumps the JSON into an array. If the file has already been created, it goes to the end, replaces the ] with a , drops the new JSON object in, and then closes it up again with another ]
# Append JSON object to output file JSON array
fname = "somefile.txt"
if os.path.isfile(fname):
# File exists
with open(fname, 'a+') as outfile:
outfile.seek(-1, os.SEEK_END)
outfile.truncate()
outfile.write(',')
json.dump(data_dict, outfile)
outfile.write(']')
else:
# Create file
with open(fname, 'w') as outfile:
array = []
array.append(data_dict)
json.dump(array, outfile)

You aren't ever writing anything to do with the data you read in. Do you want to be adding the data structure in feeds to the new one you're creating?
Or perhaps you want to open the file in append mode open(filename, 'a') and then add your string, by writing the string produced by json.dumps instead of using json.dump - but nneonneo points out that this would be invalid json.

import jsonlines
object1 = {
"name": "name1",
"url": "url1"
}
object2 = {
"name": "name2",
"url": "url2"
}
# filename.jsonl is the name of the file
with jsonlines.open("filename.jsonl", "a") as writer: # for writing
writer.write(object1)
writer.write(object2)
with jsonlines.open('filename.jsonl') as reader: # for reading
for obj in reader:
print(obj)
visit for more info https://jsonlines.readthedocs.io/en/latest/

You can simply import the data from the source file, read it, and save what you want to append to a variable. Then open the destination file, assign the list data inside to a new variable (presumably this will all be valid JSON), then use the 'append' function on this list variable and append the first variable to it. Viola, you have appended to the JSON list. Now just overwrite your destination file with the newly appended list (as JSON).
The 'a' mode in your 'open' function will not work here because it will just tack everything on to the end of the file, which will make it non-valid JSON format.

let's say you have the following dicts
d1 = {'a': 'apple'}
d2 = {'b': 'banana'}
d3 = {'c': 'carrot'}
you can turn this into a combined json like this:
master_json = str(json.dumps(d1))[:-1]+', '+str(json.dumps(d2))[1:-1]+', '+str(json.dumps(d3))[1:]
therefore, code to append to a json file will look like below:
dict_list = [d1, d2, d3]
for i, d in enumerate(d_list):
if i == 0:
#first dict
start = str(json.dumps(d))[:-1]
with open(str_file_name, mode='w') as f:
f.write(start)
else:
with open(str_file_name, mode='a') as f:
if i != (len(dict_list) - 1):
#middle dicts
mid = ','+str(json.dumps(d))[1:-1]
f.write(mid)
else:
#last dict
end = ','+str(json.dumps(d))[1:]
f.write(end)