jsonata-cli

Command Line Interface (CLI) for JSONata.

JSONata is JSON query and transformation language. It's inspired by the location 'path' semantics of XPath. JSONata allows sophisticated queries to be expressed in a compact and intuitive notation.

More about JSONata and it's capabilities can be find at it's Getting started or Github project page.

Getting Started

Installation

npm install -g jsonata-cli

Usage

To get basic usage information run the following command:

jsonata-cli -h [--help]

Display the current version of the application:

jsonata-cli -v [--version]

Query JSON file

The command to query data from the JSON type file the command should be in the following format.

jsonata-cli <query-expression> -f [--file] <JSON-file>

Where:

• query-expression - represent the JSONata location path syntax similar to XPath
• JSON-file - a file in JSON format

For the syntax of a query expression consult the JSONata Documentation.

Examples:

# list the scripts from package.json
jsonata-cli 'scripts' -f package.json

# count the number of dependencies
jsonata-cli '$sum($keys(dependencies))' -f package.json

Query JSON string

In the similar fashion to querying the file in JSON format the querying the JSON string can be performed:

jsonata-cli <query-expression> <JSON-string>

• query-expression - represent the JSONata location path syntax similar to XPath
• JSON-string - a string in JSON format

Examples:

# this query will return Address element
jsonata-cli 'Address' '{"FirstName": "Fred", "Surname": "Smith", "Age": 28, "Address": { "Street": "Hursley Park", "City": "Winchester", "Postcode": "SO21 2JN"} }'

# this query will return: Fred from Winchester
jsonata-cli 'FirstName & " from " & Address.City ' '{"FirstName": "Fred", "Surname": "Smith", "Age": 28, "Address": { "Street": "Hursley Park", "City": "Winchester", "Postcode": "SO21 2JN"} }'

# returns the list of emails of type "work": [ '[email protected]', '[email protected]' ]
jsonata-cli 'Email[type="work"].address' '{ "Email": [{"type": "work","address": ["[email protected]", "[email protected]"]},{"type": "home","address": ["[email protected]", "[email protected]"]}] }'

The real power derive from using the pipe (|).

The following example will print the date of The Sant Joan holiday in Spain for the year 2022 from a result of a public Public Holiday API call.

curl https://date.nager.at/api/v3/publicholidays/2022/ES | xargs -0 -I %% jsonata-cli '$[localName="Sant Joan"].date' %%

Development

Clone the repository

git clone https://github.com/rubystream/jsonata-cli

If you plan to contribute to this project please read the CONTRIBUTING file first.

Run tests

npm test