Python - JSON

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Python JSON(JavaScript Object Notation Serializer)

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Purpose: 

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-Encode Python objects as JSON strings, and decode JSON strings into Python objects.

-JSON is a syntax for storing and exchanging data.

-JSON is text, written with JavaScript object notation.

Uses:

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-JSON (JavaScript Object Notation) is a lightweight data-interchange format

-The JSON format is often used for serializing and transmitting structured data over a network connection.

-It is used primarily to transmit data between a server and web application(client), serving as an alternative to XML.

-It is easy for humans to read and write. 

-It is easy for machines to parse and generate. 

-It is based on a subset of the JavaScript Programming Language, Standard ECMA

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You can convert Python objects of the following types, into JSON strings:

dict, list, tuple, string, int, float, True, False, None

Difference between XML and JSON:

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-Both JSON and XML can be used to receive data from a web server.

-JSON is a Data Oriented , XML is a Document Oriented

-JSON Support arrays, XML Not support array

-JSON less secured, XML more Secured

JSON Example:

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{"employees":[

    { "firstName":"Jahab", "lastName":"Deen" },

    { "firstName":"Anna", "lastName":"Smith" },

    { "firstName":"Peter", "lastName":"Jones" }

]}

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XML Example:

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<employees>

    <employee>

        <firstName>Jahab</firstName> <lastName>Deen</lastName>

    </employee>

    <employee>

        <firstName>Anna</firstName> <lastName>Smith</lastName>

    </employee>

    <employee>

        <firstName>Peter</firstName> <lastName>Jones</lastName>

    </employee>

</employees>   

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#Program 1: Convert from JSON to Python

import json

# some JSON:

x =  '{ "name":"Jahab", "age":30, "city":"Trichy"}'

# parse x:

y = json.loads(x)

# the result is a Python dictionary:

print(y["name"])

print(y["age"])

print(y["city"])

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#Program 2: Convert from Python to JSON

import json

# a Python object (dict):

x = {

  "name": "Jahab",

  "age": 30,

  "city": "Trichy"

}

# convert into JSON:

y = json.dumps(x)

# the result is a JSON string:

print(y)

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Note:

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1) json.dumps(x, indent=4)   - Format the result

2) json.dumps(x, indent=4, separators=(". ", " = ")) - Separators

3) json.dumps(x, indent=4, sort_keys=True)   - Order the result

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#Program 3: Convert from Python to JSON

import json

print(json.dumps({"name": "Jahab", "age": 30}))

print(json.dumps(["apple", "bananas"]))

print(json.dumps(("apple", "bananas")))

print(json.dumps("hello"))

print(json.dumps(42))

print(json.dumps(31.76))

print(json.dumps(True))

print(json.dumps(False))

print(json.dumps(None))

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