How to Find a Particular JSON Value by Key

How to find a particular JSON value by key?

My approach to this problem would be different.

As JSON doesn't allow depth first search, so convert the json to a Python Object, feed it to an XML decoder and then extract the Node you are intending to search

from xml.dom.minidom import parseString
import json        
def bar(somejson, key):
    def val(node):
        # Searches for the next Element Node containing Value
        e = node.nextSibling
        while e and e.nodeType != e.ELEMENT_NODE:
            e = e.nextSibling
        return (e.getElementsByTagName('string')[0].firstChild.nodeValue if e 
                else None)
    # parse the JSON as XML
    foo_dom = parseString(xmlrpclib.dumps((json.loads(somejson),)))
    # and then search all the name tags which are P1's
    # and use the val user function to get the value
    return [val(node) for node in foo_dom.getElementsByTagName('name') 
            if node.firstChild.nodeValue in key]

bar(foo, 'P1')
[u'cccc', u'aaa', u'ss']
bar(foo, ('P1','P2'))
[u'cccc', u'cccc', u'aaa', u'ss']

How to search JSON object and extract the key/value pair?

Simply when you have the key and you need the value, you have to do this:

>>> dictionary['key']
'value'

In your case:

if item == 'name':
    print(item['name'])

Anyway you can simply omitt the if statement this way:

for item in elements:
    print(item['name'])

Find key by value in python3 json

data = {
    "1":
    {"name": "Jason"},
    "2":
    {"name": "Alex"}
}

name = 'Jason'

for key in d:
    if (d[key]['name'] == name):
        print(key) ## output 1

or in more Pythonic way:

for key, value in data.items():
    if name == value['name']:
        print(key)

Finding all JSON keys with a certain name in python

Use the following code, if there are only unique items:

def create_db(data, find, other):
    db = {}
    def recurse(data):
        if isinstance(data, list):
            for elem in data:
                recurse(elem)
        elif isinstance(data, dict):
            if find in data:
                db[data[other]] = data[find]      
            for k, v in data.items():
                recurse(v)
    recurse(data)
    return db

>>> create_db(data, 'price', 'name')
{'Apple': 3, 'Banana': 2, 'Pear': 4, 'Pineapple': 4, 'cucumber': 3, 'onion': 2}

Else:

def create_db(data, find, other):
    db = {}
    ctr = {}
    def recurse(data):
        if isinstance(data, list):
            for elem in data:
                recurse(elem)
        elif isinstance(data, dict):
            if find in data:
                if data[other] in ctr:
                    ctr[data[other]] = str(int(ctr[data[other]] or '1') + 1)
                else:
                    ctr[data[other]] = ''
                key = data[other] + ctr[data[other]]
                db[key] = data[find]      
            for k, v in data.items():
                recurse(v)
    recurse(data)
    return db

For example, if data had two Apples:

data = {'status': 'success',
 'data': {'top_products': {'products': [{'price': 3, 'name': 'Apple'},
    {'price': 4, 'name': 'Apple'},
    {'price': 2, 'name': 'Banana'}]}}}

# Second approach will add a serial number to each duplicate item
>>> create_db(data, 'price', 'name')
{'Apple': 3, 'Apple2': 4, 'Banana': 2}

For easier access in case of duplicates, you can create a nested dict:

def create_db(data, find, other):
    db = {}
    def recurse(data):
        if isinstance(data, list):
            for elem in data:
                recurse(elem)
        elif isinstance(data, dict):
            if find in data:
                if data[other] in db:
                    if isinstance(db[data[other]], dict):
                        db[data[other]][len(db[data[other]]) + 1] = data[other]
                    else:
                        db[data[other]] = {0: db.pop(data[other]), 1: data[find]}
                else:
                    db[data[other]] = data[find]      
            for k, v in data.items():
                recurse(v)
    recurse(data)
    return db

# For the data in above approach:
>>> create_db(data, 'price', 'name')
{'Apple': {0: 3, 1: 4}, 'Banana': 2}

C# find JSON value based only on Key name through multiple levels of array

You could also use linq and filter the JProperty collection based on JProperty.Name. For example

var result = JObject.Parse(jsonString)
                    .DescendantsAndSelf()
                    .OfType<JProperty>()
                    .Single(x=>x.Name.Equals("terminalSize"))
                    .Value;

How to retrieve an specific value from a JSON involving multiple key value pairs using Javascript array

Ok, so here is a hack. You can use Array as an Object and insert any key you want. You can apply forEach to it and bind keys with properties like below.

var dictionary = [{"key":"Math","value":"20"},{"key":"History","value":"10"},{"key":"Chemistry","value":"12"}]
dictionary.forEach(function(item) {  dictionary[item.key] = item;});
console.log(dictionary["History"].value);

Find the value of key from JSON

If you have a grep that can do Perl compatible regular expressions (PCRE):

$ grep -Po '"id": *\K"[^"]*"' infile.json
"4dCYd4W9i6gHQHvd"

• -P enables PCRE
• -o retains nothing but the match
• "id": * matches "id" and an arbitrary amount of spaces
• \K throws away everything to its left ("variable size positive look-behind")
• "[^"]*" matches two quotes and all the non-quotes between them

If your grep can't do that, you an use

$ grep -o '"id": *"[^"]*"' infile.json | grep -o '"[^"]*"$'
"4dCYd4W9i6gHQHvd"

This uses grep twice. The result of the first command is "id": "4dCYd4W9i6gHQHvd"; the second command removes everything but a pair of quotes and the non-quotes between them, anchored at the end of the string ($).

But, as pointed out, you shouldn't use grep for this, but a tool that can parse JSON – for example jq:

$ jq '.data.id' infile.json
"4dCYd4W9i6gHQHvd"

This is just a simple filter for the id key in the data object. To get rid of the double quotes, you can use the -r ("raw output") option:

$ jq -r '.data.id' infile.json
4dCYd4W9i6gHQHvd

jq can also neatly pretty print your JSON:

$ jq . infile.json
{
  "data": {
    "name": "test",
    "id": "4dCYd4W9i6gHQHvd",
    "domains": [
      "www.test.domain.com",
      "test.domain.com"
    ],
    "serverid": "bbBdbbHF8PajW221",
    "ssl": null,
    "runtime": "php5.6",
    "sysuserid": "4gm4K3lUerbSPfxz",
    "datecreated": 1474597357
  },
  "actionid": "WXVAAHQDCSILMYTV"
}

How to parse json to get all values of a specific key within an array?

You cannot do contents[:]["name"] since contents is a list is a dictionary with integer indexes, and you cannot access an element from it using a string name.

To fix that, you would want to iterate over the list and get the value for key name for each item

import json
contents = []

try:
    with open("./simple.json", 'r') as f:
        contents = json.load(f)
except Exception as e:
    print(e)

li = [item.get('name') for item in contents]
print(li)

The output will be

['Bulbasaur', 'Ivysaur']

How to select specific key/value of an object in json via python

You can use list comprehension and dict like this:

device_disco["device"] =[dict(username=k1["username"],password=k1["password"],ip=k1["ip"]) for k1 in 
device_disco["device"]]

jsonData = json.dumps(device_disco)
print (jsonData)

in your code:

import requests
import json

#API request details
url = 'api url'
data = '{"service":"ssh", "user_id":"0", "action":"read_by_user", 
"user":"D2", "keyword":"NULL"}'
headers = {"Content-Type": "application/json"}

#Making http request
response = requests.post(url,data=data,headers=headers,verify=False)
print(response)

#Json string
json_disco = response.text
print(type(json_disco))
print(json_disco)

#Decode response.json() method to a python dictionary and use the data
device_disco = response.json()
print(type(device_disco))
print(device_disco)
device_disco["device"] =[dict(username=k1["username"],password=k1["password"],ip=k1["ip"]) for k1 in 
device_disco["device"]]

jsonData = json.dumps(device_disco)

with open('devices.json', 'w') as fp:
json.dump(jsonData, fp, indent=4, sort_keys=True)

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