Finding Values in Python json.loads Dictionary - json

I'm working with a REST API that returns data in the following format:
{
"id": "2902cbad6da44459ad05abd1305eed14",
"displayName": "",
"sourceHost": "dev01.test.lan",
"sourceIP": "192.168.145.1",
"messagesPerSecond": 0,
"messages": 2733,
"size": 292062,
"archiveSize": 0,
"dates": [
{
"date": 1624921200000,
"messages": 279,
"size": 29753,
"archiveSize": 0
},
{
"date": 1625007600000,
"messages": 401,
"size": 42902,
"archiveSize": 0
}
]
}
I'm using json.loads to successfully pull the data from the API, and I now need to search for a particular "date:" value and read the corresponding "messages", "size" and "archiveSize" values.
I'm trying to use the "if-in" method to find the value I'm interested in, for example:
response = requests.request("GET", apiQuery, headers=headers, data=payload)
json_response = json.loads(response.text)
test = 2733
if test in json_response.values():
print(f"Yes, value: '{test}' exist in dictionary")
else:
print(f"No, value: '{test}' does not exist in dictionary")
This works fine for any value in the top section of the JSON return, but it never finds any values in the "dates" sub-branches.
I have two questions, firstly, how do I find the target "date" value? Secondly, once I find that "sub-branch" what would be the best way to extract the three values I need?
Thanks.

from json import load
def list_dates_whose_message_count_equals(dates=None, message_count=0):
return list(filter(
lambda date: date.get("messages") == message_count, dates
))
def main():
json_ = {}
with open("values.json", "r") as fp:
json_ = load(fp)
print(list_dates_whose_message_count_equals(json_["dates"], message_count=279))
print(list_dates_whose_message_count_equals(json_["dates"], message_count=401))
if __name__ == "__main__":
main()
Returns this
[{'date': 1624921200000, 'messages': 279, 'size': 29753, 'archiveSize': 0}]
[{'date': 1625007600000, 'messages': 401, 'size': 42902, 'archiveSize': 0}]

Related

json_normalize does not read all data

I have a json file that I want to flatten and retrieve all the information into a pandas dataframe. The json file looks like this:
jsonstr = {
"calculation": {
"id": "3k3k3k3kwk3kwk",
"Id": 23,
"submissionDate": 1622428064679,
"serverVersion": "3.3.5.6.r",
"tag": [
{
"code": "qq4059331155113278",
"manual": {
"location": {
"x": 26.5717,
"y": 59.4313,
"z": 0.0,
"floor": 0
},
"timestamp": 1599486138000
},
"device": null,
"measurements": [
{
"Address": "D_333",
"subcell": "",
"frequency": 14.0,
"dfId": 0
},
{
"trxAddress": "D_334",
"subcell": "",
"frequency": 11.0,
"dfId": 0
}]
}]
}
}
Now, as usual, I do the following. I thought that this would return all the "fields", including id, Id, submissionDate and so on
import os, json
import pandas as pd
import numpy as np
import glob
pd.set_option('display.max_columns', None)
file = './Testjson.json'
#file = './jsondumps/ff80818178f93bd90179ab51781e1c95.json'
with open(file) as json_string:
jsonstr = json.load(json_string)
labels = pd.json_normalize(jsonstr, record_path=['calculation','tag'])
But in fact, it returns:
code device \
0 qq4059331155113278 None
measurements manual.location.x \
0 [{'Address': 'D_333', 'subcell': '', 'frequenc... 26.5717
manual.location.y manual.location.z manual.location.floor \
0 59.4313 0.0 0
manual.timestamp
0 1599486138000
and trying the following
labels = pd.json_normalize(jsonstr, record_path=['calculation','tag'], meta=['id', 'Id'])
returns an error:
KeyError: 'id'
which makes sense. But What am I doing wrong to begin with? Why can I not get all the fields under calculation since they are in the path?
Greatful for any insights!
Your syntax is slightly off on the meta argument. id and Id are at the end of the dataframe.
If you are looking to flatten the entire json, look into flatten_json. It's a pretty good library to use with nested json.
pd.json_normalize(jsonstr, record_path=['calculation','tag'], meta=[['calculation','id'],['calculation','Id']])
code device measurements manual.location.x manual.location.y manual.location.z manual.location.floor manual.timestamp calculation.id calculation.Id
0 qq4059331155113278 null [{'Address': 'D_333', 'subcell': '', 'frequenc... 26.5717 59.4313 0.0 0 1599486138000 3k3k3k3kwk3kwk 23

Flatten JSON data to individual columns

I am working upon Twitter streaming data and I am having an output like this:
"data": {
"author_id": "1318123716522479616",
"created_at": "2020-11-05T04:18:21.000Z",
"entities": {
"hashtags": [
{
"end": 107,
"start": 86,
"tag": "MilliHesaplarYanyana"
}
],
"mentions": [
{
"end": 15,
"start": 3,
"username": "MilliTaakip"
}
]
},
"id": "1324204381177323520",
"lang": "tr",
"text": "RT #MilliTaakip: Milli hesaplar\u0131m\u0131z\u0131n g\u00fc\u00e7lenmesi i\u00e7in\nCumhurba\u015fkan\u0131m\u0131z\u0131n talimat\u0131yla,\n#MilliHesaplarYanyana \u00e7al\u0131\u015fmas\u0131n\u0131 destekliyoruz;\n\n\ud83c\uddf9\ud83c\uddf7\u2026"
}
}
I want to extract specific information like the hashtags from this data and store them in my database.
I tried using multiple ways like json.normalize ,flatten_json but it does not work. I get the following as my output
here's my code:
def connect_to_endpoint(url, headers):
response = requests.request("GET", url, headers=headers, stream=True, params=payload)
print(response.status_code)
for response_line in response.iter_lines():
if response_line:
# print(ndjson.dumps(json_response["data"]["text"], indent=4, sort_keys=True))
conn = psycopg2.connect(database="tweetData", user="postgres", password="pass", host="localhost", port="5432")
cur = conn.cursor()
# cc
try:
data = json.loads(response_line.decode('utf-8'))
index = 0
#for created at
var2 = json.loads(response_line.decode('utf-8'))["data"]["text"]
# define a list of keywords
keywords = ('biden', 'election', 'trump','stocks')
if any(keyword in var2.lower() for keyword in keywords):
df= pd.json_normalize(data)
dffinal=pd.DataFrame(df)
engine = create_engine('postgresql+psycopg2://postgres:root#localhost:5432/tweetData')
dffinal.to_sql("new-tweets", engine,if_exists='append',dtype = {'relevant_column':sqlalchemy.types.JSON})
print("loaded")
else:
print("none")
conn.commit()
index += 1
cur.close()
except IOError as io:
print("ERROR!")
if response.status_code != 200:
raise Exception(
"Request returned an error: {} {}".format(
response.status_code, response.text
)
)
Please advise on how should I proceed and what errors I have in my approach
EDIT:
Every time I try to retrieve the tweet data, in case there is no entities or no hashtags in the tweet data, it sends an error saying Key Error: 'entities'
In PostgreSQL you could use
SELECT value ->> 'tag'
FROM jsonb_array_elements(your_json #> '{data,entities,hashtags}') AS x(value);
to extract the tags.

Join nested JSON dataframe and another dataframe

I am trying to join a dataframe1 generated by the JSON with dataframe2 using the field order_id, then assign the "status" from dataframe2 to the "status" of dataframe1. Anyone knows how to do this. Many thanks for your help.
dataframe1
[{
"client_id": 1,
"name": "Test01",
"olist": [{
"order_id": 10000,
"order_dt_tm": "2012-12-01",
"status": "" <== use "status" from dataframe2 to populate this field
},
{
"order_id": 10000,
"order_dt_tm": "2012-12-01",
"status": ""
}
]
},
{
"client_id": 2,
"name": "Test02",
"olist": [{
"order_id": 10002,
"order_dt_tm": "2012-12-01",
"status": ""
},
{
"order_id": 10003,
"order_dt_tm": "2012-12-01",
"status": ""
}
]
}
]
dataframe2
order_id status
10002 "Delivered"
10001 "Ordered"
Here is your raw dataset as a json string:
d = """[{
"client_id": 1,
"name": "Test01",
"olist": [{
"order_id": 10000,
"order_dt_tm": "2012-12-01",
"status": ""
},
{
"order_id": 10000,
"order_dt_tm": "2012-12-01",
"status": ""
}
]
},
{
"client_id": 2,
"name": "Test02",
"olist": [{
"order_id": 10002,
"order_dt_tm": "2012-12-01",
"status": ""
},
{
"order_id": 10003,
"order_dt_tm": "2012-12-01",
"status": ""
}
]
}
]"""
Firstly, I would load it as json:
import json
data = json.loads(d)
Then, I would turn it into a Pandas dataframe, notice that I remove status field as it will be populated by the join step :
df1 = pd.json_normalize(data, 'olist')[['order_id', 'order_dt_tm']]
Then, from the second dataframe sample, I would do a left join using merge function:
data = {'order_id':[10002, 10001],'status':['Delivered', 'Ordered']}
df2 = pd.DataFrame(data)
result = df1.merge(df2, on='order_id', how='left')
Good luck
UPDATE
# JSON to Dataframe
df1 = pd.json_normalize(data)
# Sub JSON to dataframe
df1['sub_df'] = df1['olist'].apply(lambda x: pd.json_normalize(x).drop('status', axis=1))
# Build second dataframe
data2 = {'order_id':[10002, 10001],'status':['Delivered', 'Ordered']}
df2 = pd.DataFrame(data2)
# Populates status in sub dataframes
df1['sub_df'] = df1['sub_df'].apply(lambda x: x.merge(df2, on='order_id', how='left').fillna(''))
# Sub dataframes back to JSON
def back_to_json_str(df):
# turns a df back to string json
return str(df.to_json(orient="records", indent=4))
df1['olist'] = df1['sub_df'].apply(lambda x: back_to_json_str(x))
# Global DF back to JSON string
parsed = str(df1.drop('sub_df', axis=1).to_json(orient="records", indent=4))
parsed = parsed.replace(r'\n', '\n')
parsed = parsed.replace(r'\"', '\"')
# Print result
print(parsed)
UPDATE 2
here is a way to add index colum to a dataframe:
df1['index'] = [e for e in range(df1.shape[0])]
This is my code assigning title values from a dataframe back to the JSON object. The assignment operation takes a bit time if the number records in the JSON object is 100000. Anyone knows how to improve the performance of this code. Many thanks.
import json
import random
import pandas as pd
import pydash as _
data = [{"pid":1,"name":"Test1","title":""},{"pid":2,"name":"Test2","title":""}] # 5000 records
# dataframe1
df = pd.json_normalize(data)
# dataframe2
pid = [x for x in range(1, 5000)]
title_set = ["Boss", "CEO", "CFO", "PMO", "Team Lead"]
titles = [title_set[random.randrange(0, 5)] for x in range(1, 5000)]
df2 = pd.DataFrame({'pid': pid, 'title': titles})
#left join dataframe1 and dataframe2
df3 = df.merge(df2, on='pid', how='left')
#assign title values from dataframe back to the json object
for row in df3.iterrows():
idx = _.find_index(data, lambda x: x['pid'] == row[1]['pid'])
data[idx]['title'] = row[1]['title_y']
print(data)

AttributeError: 'list' object has no attribute 'get'?

This is the script
def validate_record_schema(record):
device = record.get('Payload', {})
manual_added= device.get('ManualAdded', None)
location = device.get('Location', None)
if isinstance(manual_added, dict) and isinstance(location, dict):
if 'Value' in manual_added and 'Value' in location:
return False
return isinstance(manual_added, bool) and isinstance(location, str)
print([validate_record_schema(r) for r in data])
This is json data
data = [{
"Id": "12",
"Type": "DevicePropertyChangedEvent",
"Payload": [{
"DeviceType": "producttype",
"DeviceId": 2,
"IsFast": false,
"Payload": {
"DeviceInstanceId": 2,
"IsResetNeeded": false,
"ProductType": "product",
"Product": {
"Family": "home"
},
"Device": {
"DeviceFirmwareUpdate": {
"DeviceUpdateStatus": null,
"DeviceUpdateInProgress": null,
"DeviceUpdateProgress": null,
"LastDeviceUpdateId": null
},
"ManualAdded": {
"value":false
},
"Name": {
"Value": "Jigital60asew",
"IsUnique": true
},
"State": null,
"Location": {
"value":"bangalore"
},
"Serial": null,
"Version": "2.0.1.100"
}
}
}]
}]
For the line device = device.get('ManualAdded', None), I am getting the following error: AttributeError: 'list' object has no attribute 'get'.
please have a look and help me to solve this issue
Where i am doing mistake...
How can i fix this error?
Please help me to solve this issue
You are having problems tracking types as you traverse data. One trick is to add prints along the way for debug to see what is going on. For instance, that top "Payload" object is a list of dict, not a single dict. The list implies that you can have more than one device descriptor so I wrote a sample that checks all of them and returns False if it finds something wrong along the way. you will likely need to update this according to your validation rules, but this will get you started.
def validate_record_schema(record):
"""Validate that the 0 or more Payload dicts in record
use proper types"""
err_path = "root"
try:
for device in record.get('Payload', []):
payload = device.get('Payload', None)
if payload is None:
# its okay to have device without payload?
continue
device = payload["Device"]
if not isinstance(device["ManualAdded"]["value"], bool):
return False
if not isinstance(device["Location"]["value"], str):
return False
except KeyError as e:
print("missing key")
return False
return True
As the error suggests, you can't .get() on a list. To get the Location and ManualAdded field, you could use:
manual_added = record.get('Payload')[0].get('Payload').get('Device').get('ManualAdded')
location = record.get('Payload')[0].get('Payload').get('Device').get('Location')
So your function would become:
def validate_record_schema(record):
manual_added = record.get('Payload')[0].get('Payload').get('Device').get('ManualAdded')
location = record.get('Payload')[0].get('Payload').get('Device').get('Location')
if isinstance(manual_added, dict) and isinstance(location, dict):
if 'Value' in manual_added and 'Value' in location:
return False
return isinstance(manual_added, bool) and isinstance(location, str)
Note that this would set location to
{
"value":"bangalore"
}
and manual_added to
{
"value":false
}

How to Get JSON values Python

Learning Days
Code to the get the data in JSON Format
#...
cursor.execute("SELECT * FROM user")
response = {
"version": "5.2",
"user_type": "online",
"user": list(cursor),
}
response = json.dumps(response, sort_keys=False, indent=4, separators=(',', ': '))
print(response)
# ...
This produces output as
{
"version": "5.2",
"user_type": "online",
"user":
[
{
"name": "John",
"id": 50
},
{
"name": "Mark",
"id": 57
}
]
}
print(response["user"]) - TypeError: string indices must be integers
How do i access the values in JSON
json.dumps return a string, need a small conversion something like this, not sure is this the exact method to do
Solution:
response = JSONEncoder().encode(response )
response = JSONDecoder().decode(response )
response = json.loads(response )
print(response['user'[0]['id'])