What is Swush

Overview

Swush (pronounce s-woo-sh) is a simple data exchange language that is designed to be easy for people to read and manipulate (unlike XML, which is designed to be difficult for both people and for machines)
A Swush file can be as simple as a key:value list, or a complex nested structure.

Specification

Before I get into details, here is a sample swush file:
The following is an example of a swush file with all of the above elements:

@swush 1.0 utf-8

server{
	connector{
		/*
			multiline
			comment
		 */
		protocol : http // singleline comment
		port : 8080		# singleline comment
		host : localhost
		admin_emails {
			root@localhost
			john@dawg.com
		}
	}

	log{
		output{
			file : /var/log/server.log
			format : %t%s
		}
	}

	contact{
		name: "Omry Yadan"
		email: john@dawg.com
	}
}

Swush ignores whitespaces, unless they are inside a quoted string.
Each node is a list of Swush elements, each element can one of:

Each node is a list of Swush elements, each element can be:

  1. a key-value pair, for example, this the following line key is format and the value is %s%t :
    format:%s%t
  2. a String, for example, the following node is named drinks and contains 3 string elements:
    drinks{ Coffee Tea “Bloody marry” }
  3. a name followed by a swush node inside curly brackets, for example – the following swush node is named server, and contains a key:value pair:
    server{
    host:localhost
    }

A swush file must begin with an header line:

@swush 1.0 [encoding]

where encoding is optional and is the encoding of the file (default is utf-8)

Comments

Swush supports two types of comments:

  1. C Multiline comments
  2. C++/Bash style single line comments

Some examples:

	/* a multil
	line
	comment */
	// Single line comment
	# Another single line comment
	key:value # Trailing single line comment

Selectors

Swush implementation supports a simple selector language that allow the user to easily access nested nodes.
for example, given supposed we have the following swush file:

@swush 1.0
addressbook{
	entry{
		name: "John dog"
		email: dog@john.com
	}

	entry{
		name: "Jane bitch"
		email: jane@bitch.org
	}
}

the following selector will select the two entries:
addressbook.entry

an empty selector matches all the nodes in the root of the file.
in the future, it’s possible that the selectors language will become more powerful.

Java Implementation

Usage example:

java -jar swush-x.y.jar swush.file selector

Programmatic usage example:

public class Example
{
	public static void main(String[] args) throws SwushException, IOException
	{
		// You can construct a swush object in several ways:

		// by parsing a file
		Swush fromFile = new Swush(new File("test-data/test1/file.swush"));

		// straight from a string
		Swush fromString = Swush.fromString("swush:rocks node{a:b}");

		// programatically
		Swush root = Swush.node("node1");
		root.addPair("key","value");
		Swush node2 = root.addNode("node2");
		node2.addPair("key", "value1");
		node2.addPair("key", "value2");
		node2.addArray("array", "a", "b", "c");

		// This will select the two key-value nodes and the array node in node2:
		List selected = root.select("node2.key");

		// Selects the first key in node2
		Swush first = root.selectFirst("node2.key");

		// Selects the value of the first node2.key element ("value1")
		String value = root.selectProperty("node2.key");
	}
}

You can download swush from here.

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