config

This package implements a basic configuration file parser language which provides a structure similar to what you would find on Microsoft Windows INI files.

The configuration file consists of sections, led by a "[section]" header and followed by "name: value" entries; "name=value" is also accepted. Note that leading whitespace is removed from values. The optional values can contain format strings which refer to other values in the same section, or values in a special DEFAULT section. Additional defaults can be provided on initialization and retrieval. Comments are indicated by ";" or "#"; a comment may begin anywhere on a line, including on the same line after parameters or section declarations.

For example:

[My Section]
foodir: %(dir)s/whatever
dir=foo

would resolve the "%(dir)s" to the value of "dir" (foo in this case). All reference expansions are done on demand.

The functionality and workflow is loosely based on the configparser package of the Python Standard Library.

Installation

go get github.com/revel/config

Operating instructions

Given a sample configuration file:

[DEFAULT]
host: www.example.com
protocol: http://
base-url: %(protocol)s%(host)s

[service-1]
url: %(base-url)s/some/path
delegation: on
maxclients: 200 # do not set this higher
comments: This is a multi-line
	entry	# And this is a comment

To read this configuration file, do:

c, _ := config.ReadDefault("config.cfg")

c.String("service-1", "url")
// result is string "http://www.example.com/some/path"

c.Int("service-1", "maxclients")
// result is int 200

c.Bool("service-1", "delegation")
// result is bool true

c.String("service-1", "comments")
// result is string "This is a multi-line\nentry"

Note the support for unfolding variables (such as %(base-url)s), which are read from the special (reserved) section name [DEFAULT].

A new configuration file can also be created with:

c := config.NewDefault()
c.AddSection("Section")
c.AddOption("Section", "option", "value")
c.WriteFile("config.cfg", 0644, "A header for this file")

This results in the file:

# A header for this file

[Section]
option: value

Note that sections, options and values are all case-sensitive.

License

The source files are distributed under the Mozilla Public License, version 2.0, unless otherwise noted.
Please read the FAQ if you have further questions regarding the license.