I have big size of json file to parse with python, however it's incomplete (i.e., missing parentheses in the end). The json file consist of one big json object which contains json objects inside. All json object in outer json object is complete, just finishing parenthese are missing.
for example, its structure is like this.
{bigger_json_head:value, another_key:[{small_complete_json1},{small_complete_json2}, ...,{small_complete_json_n},
So final "]}" are missing. however, each small json forms a single row so when I tried to print each line of the json file I have, I get each json object as a single string.
so I've tried to use:
with open("file.json","r",encoding="UTF-8") as f:
for line in f.readlines()
line_arr.append(line)
I expected to have a list with line of json object as its element
and then I tried below after the process:
for json_line in line_arr:
try:
json_str = json.loads(json_line)
print(json_str)
except json.decoder.JSONDecodeError:
continue
I expected from this code block, except first and last string, this code would print json string to console. However, it printed nothing and just got decode error.
Is there anyone who solved similar problem? please help. Thank you
If the faulty json file only miss the final "]}", then you can actually fix it before parse it.
Here is an example code to illustrate:
with open("file.json","r",encoding="UTF-8") as f:
faulty_json_str = f.read()
fixed_json_str = faulty_json_str + ']}'
json_obj = json.loads(fixed_json_str)
Related
As I know json.loads() take string as input, so I don't know why below code doesn't work.
import json
fileref = open("olympics.txt", "r").readline() # the output is str
print(fileref)
print(type(fileref))
d = json.loads(fileref)
Error:
ExternalError: SyntaxError: Unexpected token N in JSON at position 0 on line 8
Thank you!
Thats because fileref is not a syntactically valid JSON string. Unless you know the first line of the file is supposed to be a JSON object then I'm assuming the entire file is a JSON object (which is common). You can use the json.load function to read in a file https://docs.python.org/2/library/json.html.
Or you could store the file into a string and then use loads like
content = ""
with open("file.txt","r") as f:
for line in f:
content += line
json.loads(content)
EDIT: I do not know you're file structure, I am just assuming that its a JSON file (i.e its all JSON). If that is the case then what I mentioned would be accurate. Otherwise the error you are seeing is because the string being parsed is not valid JSON.
This question might have been asked many times but I am still unable to understand how to use json file. I use json.dump(data, filename). While dumping I get unnecessary {} at the end of the file. So json.load(data) gives me below error.
simplejson.scanner.JSONDecodeError: Extra data: line 1 column 1865 - line 1 column 1867 (char 1864 - 1866)
I read that there is no way to load a first or second dictionary. I have also read that there is a separater which can be used with json dump but I see no use here. Should I be using encoding, decoding here?
My json.dump file:
{
"deployCI2": ["094fd196-20f0-4e8d-b946-f74a56d2f319", "6a1ce382-98c6-4058-a929-95a7d2415fd0"],
"deployCI3": ["c8fff661-4482-4908-b722-4fac0227a8b0", "929cf1fa-3fa6-4f95-8464-d58e5490f4cf"],
"deployCI4": ["9f8ffa3c-460d-43a9-8113-58e891340e1b", "6e535e92-4da2-4228-a6ab-c8fc8d31adcd", "8e26a35e-7fb9-43b3-8026-d1283f7b678c", "f40e5c29-b4df-4cfb-9d7f-3bcc9c4dcf9f"],
"HeenaStackABC": [], "HeenaStackABC-DISK_VM1-mm55lkkvccej": ["cc2a89a2-3b27-4f88-af09-b3b0b1301056"]
}{}
Edited: I think the code is doing something here.
with open('stackList.json', 'a') as f:
for stack in stacks:
try:
hlist = hc.resources.list(stack_id=stack.id)
vlist = [o.physical_resource_id for o in hlist if o.resource_type =='OS::Cinder::Volume']
myDict[stack.stack_name] = vlist
except heatclient.exc.HTTPBadRequest as e:
pass
json.dump(myDict,f)
I edited the code like below. I hope this is valid. It removed the last braces
if len(myDict) != 0:
json.dump(myDict, f)
Your problem is here :
with open('stackList.json', 'a') as f:
You're opening the file in 'append' mode, so each time the code is executed it appends the dump to your file. The result you complain about comes from this and mydict being empty on the second run.
You either have to open the file in "w" ("write") mode which will overwrite the existing content (you can eventually create a new dump file for each call) or switch to the "jsonline" format (but your file will NOT be a valid json file anymore and any code reading it will have to know to parse it as jsonlines)
I'm using twitter's API to download raw tweets so I can play with them. The iterator loop they gave in the example looks something like this (I added an if condition to run the loop n times, not shown here):
iterator = twitter_stream.statuses.sample()
for tweet in iterator:
print (json.dumps(tweet))
break
These commands output the entire JSON object in the correct format.
To extract the "text" item from the raw tweet json object, I tried using the .get("text") operator on the
txts = []
for tweet in iterator:
txts.append((json.dumps(tweet)).get("text"))
break
print (txts)
But I get an error saying "AttributeError: 'str' object has no attribute 'get'"
So I searched around and found a solution where they wrote all the outputs from json.dumps(tweet) to a file, use json.loads(jsonfile) to a variable, and tried to use the .get("text") operator on it to load the text:
fl = open("ipjson.json", "a")
for tweet in iterator:
fl.write(json.dumps(tweet))
break
fl.flush()
decode = json.loads(fl)
for item in decode:
txt = item.get("text")
txts.append(txt)
print (txts)
But this gives me another error saying "TypeError: the JSON object must be str, not 'TextIOWrapper'"
What am I doing wrong? Is there a better/easier way to extract text from a raw tweet JSON object?
For the first example you don't need JSON you can just do:
txts = []
for status in statuses:
txts.append(status.text)
For the second example you're handling the JSON incorrectly. You should instead do:
txts = []
for status in statuses:
txts.append(json.dumps(status))
with open('ipjson.json','w') as fou:
json.dump(txts,fou)
And to read it back in:
with open('ipjson.json','r') as fin:
txts = json.load(fin)
for txt in txts:
print(json.loads(txt)['text'])
Please note that when you're writing and reading the JSON you use dump and load but with the individual JSON objects you're using dumps and loads.
JSON files require recursive scanning,
https://stackoverflow.com/a/42855667/3342050
or known locations within the structure.
After you get your dict, list, & entries, you parse through for specific values:
https://stackoverflow.com/a/42860573/3342050
This is entirely dependent upon what data is returned,
because keys will be unique to that structure.
I have a file containing in each row a JSON object, which means that the whole file is not a valid JSON, but only each row by itself is.
What I'm trying to do is to iterate through the file and convert each row into a JSON and then print the values, simple because only each row by itself is a valid JSON.
The file looks like this:
{json object 1}
{json object 2}
{json object 3}
{json object 4}
each JSON object looks like this:
{"event":"Session","properties":{"time":1423353612,"duration":33}}
The code I'm trying to run with no success is the following:
import simplejson as json
with open("sessions.json", "r") as f:
for line in f:
j=json.JSONEncoder().encode(line)
print j['event']['time']
print j['event']['duration']
I'm getting the following error:
TypeError: string indices must be integers, not str
Any ideas why?
Thanks!
You're calling the wrong thing. Converting from a JSON string to a Python object is decoding, not encoding. And in any case, it's better to use the top-level functions in the json module, rather than the underlying classes themselves.
for line in f:
j = json.loads(line)
Edit
Given the structure you show, j['event'] is the string "Session" and it does not have a sub-property time. Looks like you mean j['properties']['time'].
I am downloading Json files from an API, I use the following code to write the JSON. Each item the loop gives me a JSON file. I need to save it and extract entities from the appended JSON file using a loop.
for item in style_ls:
dat = get_json(api, item)
specs_dict[item] = dat
with open("specs_append.txt", "a") as myfile:
json.dump(dat, myfile)
myfile.close()
print item
with open ("specs_data.txt", "w") as my file:
json.dump(spec_dict, myfile)
myfile.close()
I know that I cannot get a valid JSON format from the specs_append.txt, but I can get one from the specs_data.txt. I am doing the first one just because my program needs atleast 3-4 days to complete and there are high chances that my system may shutdown. So is there anyway I can do this efficiently ?
If not is there anyway I can extract it from specs_append.txt <{JSON}{JSON}> format (which is not a valid JSON format)?
If not should I write specs_dict to a txt file every time in the loop, so that even if program gets terminated i can start if from that point in loop and still get a valid json format?
I suggest several possible solutions.
One solution is to write custom code to slurp in the input file. I would suggest putting a special line before each JSON object in the file, such as: ###
Then you could write code like this:
import json
def json_get_objects(f):
temp = ''
line = next(f) # pull first line
assert line == SPECIAL_LINE
for line in f:
if line != SPECIAL_LINE:
temp += line
else:
# found special marker, temp now contains a complete JSON object
j = json.loads(temp)
yield j
temp = ''
# after loop done, yield up last JSON object
if temp:
j = json.loads(temp)
yield j
with open("specs_data.txt", "r") as f:
for j in json_get_objects(f):
pass # do something with JSON object j
Two notes on this. First, I am simply appending to a string over and over; this used to be a very slow way to do this in Python, so if you are using a very old version of Python, don't do it this way unless your JSON objects are very small. Second, I wrote code to split the input and yield up JSON objects one at a time, but you could also use a guaranteed-unique string, slurp in all the data with a single call to f.read() and then split on your guaranteed-unique string using the str.split() method function.
Another solution would be to write the whole file as a valid JSON list of valid JSON objects. Write the file like this:
{"mylist":[
# first JSON object, followed by a comma
# second JSON object, followed by a comma
# third JSON object
]}
This would require your file appending code to open the file with writing permission, and seek to the last ] in the file before writing a comma plus newline, then the new JSON object on the end, and then finally writing ]} to close out the file. If you do it this way, you can use json.loads() to slurp the whole thing in and have a list of JSON objects.
Finally, I suggest that maybe you should just use a database. Use SQLite or something and just throw the JSON strings in to a table. If you choose this, I suggest using an ORM to make your life simple, rather than writing SQL commands by hand.
Personally, I favor the first suggestion: write in a special line like ###, then have custom code to split the input on those marks and then get the JSON objects.
EDIT: Okay, the first suggestion was sort of assuming that the JSON was formatted for human readability, with a bunch of short lines:
{
"foo": 0,
"bar": 1,
"baz": 2
}
But it's all run together as one big long line:
{"foo":0,"bar":1,"baz":2}
Here are three ways to fix this.
0) write a newline before the ### and after it, like so:
###
{"foo":0,"bar":1,"baz":2}
###
{"foo":0,"bar":1,"baz":2}
Then each input line will alternately be ### or a complete JSON object.
1) As long as SPECIAL_LINE is completely unique (never appears inside a string in the JSON) you can do this:
with open("specs_data.txt", "r") as f:
temp = f.read() # read entire file contents
lst = temp.split(SPECIAL_LINE)
json_objects = [json.loads(x) for x in lst]
for j in json_objects:
pass # do something with JSON object j
The .split() method function can split up the temp string into JSON objects for you.
2) If you are certain that each JSON object will never have a newline character inside it, you could simply write JSON objects to the file, one after another, putting a newline after each; then assume that each line is a JSON object:
import json
def json_get_objects(f):
for line in f:
if line.strip():
yield json.loads(line)
with open("specs_data.txt", "r") as f:
for j in json_get_objects(f):
pass # do something with JSON object j
I like the simplicity of option (2), but I like the reliability of option (0). If a newline ever got written in as part of a JSON object, option (0) would still work, but option (2) would error.
Again, you can also simply use an actual database (SQLite) with an ORM and let the database worry about the details.
Good luck.
Append json data to a dict on every loop.
In the end dump this dict as a json and write it to a file.
For getting you an idea for appending data to dict:
>>> d1 = {'suku':12}
>>> t1 = {'suku1':212}
>>> d1.update(t1)
>>> d1
{'suku1': 212, 'suku': 12}