What is JSON?
JSON (JavaScript Object Notation) is a compact, text based format for computers to exchange data. The official Internet media type for JSON is application/json, and the JSON filename extension is .json
JSON is built on two structures:
A collection of name/value pairs
An ordered list of values.
JSON take these forms: objects, array, value, string, number
Object
Unordered set of name/value pairs. Begins with { and ends with }. Each name is followed by : (colon) The name/value pairs are separated by , (comma).
Array
Ordered collection of values. Begins with [ and ends with ]. Values are separated by , (comma).
Value
Can be a string in double quotes, number, or true or false or null, or an object or an array.
String
A sequence of zero or more Unicode characters, wrapped in double quotes, using backslash escapes.
Number
Integer, long, float
The following example shows the JSON representation of an object that describes a person:
{ "firstName": "John", "lastName": "Smith", "age": 25, "address": { "streetAddress": "21 2nd Street", "city": "New York", "state": "NY", "postalCode": "10021" }, "phoneNumber": [ { "type": "home", "number": "212 555-1234" }, { "type": "fax", "number": "646 555-4567" } ] }
JSON data structures map directly to Python data types, so this is a powerful tool for directly accessing data without having to write any XML parsing code. JSON is once loaded into Python just like a dictionary.