Pretty-Print JSON Data to a File using Python

问题

A project for class involves parsing Twitter JSON data. I'm getting the data and setting it to the file without much trouble, but it's all in one line. This is fine for the data manipulation I'm trying to do, but the file is ridiculously hard to read and I can't examine it very well, making the code writing for the data manipulation part very difficult.

Does anyone know how to do that from within Python (i.e. not using the command line tool, which I can't get to work)? Here's my code so far:

header, output = client.request(twitterRequest, method="GET", body=None,
                            headers=None, force_auth_header=True)

# now write output to a file
twitterDataFile = open("twitterData.json", "wb")
# magic happens here to make it pretty-printed
twitterDataFile.write(output)
twitterDataFile.close()

Note I appreciate people pointing me to simplejson documentation and such, but as I have stated, I have already looked at that and continue to need assistance. A truly helpful reply will be more detailed and explanatory than the examples found there. Thanks

Also: Trying this in the windows command line:

more twitterData.json | python -mjson.tool > twitterData-pretty.json

results in this:

Invalid control character at: line 1 column 65535 (char 65535)

I'd give you the data I'm using, but it's very large and you've already seen the code I used to make the file.

回答1:

header, output = client.request(twitterRequest, method="GET", body=None,
                            headers=None, force_auth_header=True)

# now write output to a file
twitterDataFile = open("twitterData.json", "w")
# magic happens here to make it pretty-printed
twitterDataFile.write(simplejson.dumps(simplejson.loads(output), indent=4, sort_keys=True))
twitterDataFile.close()

回答2:

You can parse the JSON, then output it again with indents like this:

import json
mydata = json.loads(output)
print json.dumps(mydata, indent=4)

See http://docs.python.org/library/json.html for more info.

回答3:

import json

with open("twitterdata.json", "w") as twitter_data_file:
    json.dump(output, twitter_data_file, indent=4, sort_keys=True)

You don't need json.dumps() if you don't want to parse the string later, just simply use json.dump(). It's faster too.

回答4:

You can use json module of python to pretty print.

>>> import json
>>> print json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4)
{
    "4": 5,
    "6": 7
}

So, in your case

>>> print json.dumps(json_output, indent=4)

回答5:

If you already have existing JSON files which you want to pretty format you could use this:

    with open('twitterdata.json', 'r+') as f:
        data = json.load(f)
        f.seek(0)
        json.dump(data, f, indent=4)
        f.truncate()

回答6:

If you are generating new *.json or modifying existing josn file the use "indent" parameter for pretty view json format.

import json
responseData = json.loads(output)
with open('twitterData.json','w') as twitterDataFile:    
    json.dump(responseData, twitterDataFile, indent=4)

回答7:

You could redirect a file to python and open using the tool and to read it use more.

The sample code will be,

cat filename.json | python -m json.tool | more

来源：https://stackoverflow.com/questions/9170288/pretty-print-json-data-to-a-file-using-python