Config::JSON - A JSON based config file system.
version 1.5202
use Config::JSON;
my $config = Config::JSON->create($pathToFile);
my $config = Config::JSON->new($pathToFile);
my $config = Config::JSON->new(pathToFile=>$pathToFile);
my $element = $config->get($directive);
$config->set($directive,$value);
$config->delete($directive);
$config->deleteFromHash($directive, $key);
$config->deleteFromArray($directive, $value);
$config->addToHash($directive, $key, $value);
$config->addToArray($directive, $value);
my $path = $config->pathToFile;
my $filename = $config->getFilename;
# config-file-type: JSON 1
{
"dsn" : "DBI:mysql:test",
"user" : "tester",
"password" : "xxxxxx",
# some colors to choose from
"colors" : [ "red", "green", "blue" ],
# some statistics
"stats" : {
"health" : 32,
"vitality" : 11
},
# including another file
"includes" : ["macros.conf"]
}
This package parses the config files written in JSON. It also does some non-JSON
stuff, like allowing for comments in the files.
If you want to see it in action, it is used as the config file system in WebGUI
<
http://www.webgui.org/>.
Why build yet another config file system? Well there are a number of reasons: We
used to use other config file parsers, but we kept running into limitations.
We already use JSON in our app, so using JSON to store config files means
using less memory because we already have the JSON parser in memory. In
addition, with JSON we can have any number of hierarchcal data structures
represented in the config file, whereas most config files will give you only
one level of hierarchy, if any at all. JSON parses faster than XML and YAML.
JSON is easier to read and edit than XML. Many other config file systems allow
you to read a config file, but they don't provide any mechanism or utilities
to write back to it. JSON is taint safe. JSON is easily parsed by languages
other than Perl when we need to do that.
You may of course access a directive called "foo", but since the
config is basically a hash you can traverse multiple elements of the hash when
specifying a directive name by simply delimiting each level with a slash, like
"foo/bar". For example you may:
my $vitality = $config->get("stats/vitality");
$config->set("stats/vitality", 15);
You may do this wherever you specify a directive name.
You can put comments in the config file as long as # is the first non-space
character on the line. However, if you use this API to write to the config
file, your comments will be eliminated.
There is a special directive called "includes", which is an array of
include files that may be brought in to the config. Even the files you include
can have an "includes" directive, so you can do hierarchical
includes.
Any directive in the main file will take precedence over the directives in the
includes. Likewise the files listed first in the "includes"
directive will have precedence over the files that come after it. When writing
to the files, the same precedence is followed.
If you're setting a new directive that doesn't currently exist, it will only be
written to the main file.
If a directive is deleted, it will be deleted from all files, including the
includes.
Adds a value to an array directive in the config file.
directive
The name of the array.
value
The value to add.
Inserts a value into an array immediately before another item. If that item
can't be found, inserts at the beginning on the array.
directive
The name of the array.
insertBefore
The value to search for and base the positioning on.
value
The value to insert.
Inserts a value into an array immediately after another item. If that item can't
be found, inserts at the end on the array.
directive
The name of the array.
insertAfter
The value to search for and base the positioning on.
value
The value to insert.
Adds a value to a hash directive in the config file.
NOTE: This is really
the same as $config->set("directive/key", $value);
directive
The name of the hash.
key
The key to add.
value
The value to add.
Constructor. Creates a new empty config file.
pathToFile
The path and filename of the file to create.
Deletes a key from the config file.
directive
The name of the directive to delete.
Deletes a value from an array directive in the config file.
directive
The name of the array.
value
The value to delete.
Delete a key from a hash directive in the config file.
NOTE: This is
really just the same as doing $config->delete("directive/key");
directive
The name of the hash.
key
The key to delete.
Returns the value of a particular directive from the config file.
directive
The name of the directive to return.
Returns the filename for this config.
Returns the filename and path for this config. May also be called as
"getFilePath" for backward campatibility sake.
Returns an array reference of Config::JSON objects that are files included by
this config. May also be called as "getIncludes" for backward
compatibility sake.
Constructor. Builds an object around a config file.
pathToFile
A string representing a path such as "/etc/my-cool-config.conf".
Creates a new or updates an existing directive in the config file.
directive
A directive name.
value
The value to set the paraemter to. Can be a scalar, hash reference, or array
reference.
Returns an array of key parts.
key
A key string. Could be 'foo' (simple key), 'foo/bar' (a multilevel key referring
to the bar key as a child of foo), or 'foo\/bar' (a simple key that contains a
slash in the key). Don't forget to double escape in your perl code if you have
a slash in your key parts like this:
$config->get('foo\\/bar');
Writes the file to the filesystem. Normally you'd never need to call this as
it's called automatically by the other methods when a change occurs.
- "Couldn't parse JSON in config file"
- This means that the config file does not appear to be
formatted properly as a JSON file. Common mistakes are missing commas or
trailing commas on the end of a list.
- "Cannot read config file"
- We couldn't read the config file. This usually means that
the path specified in the constructor is incorrect.
- "Can't write to config file"
- We couldn't write to the config file. This usually means
that the file system is full, or the that the file is write
protected.
JSON Moo List::Util Test::More Test::Deep
- Repository
- <http://github.com/plainblack/Config-JSON>
- Bug Reports
- <http://rt.cpan.org/Public/Dist/Display.html?Name=Config-JSON>
JT Smith <jt-at-plainblack-dot-com>
Config::JSON is Copyright 2009 Plain Black Corporation
(<
http://www.plainblack.com/>) and is licensed under the same terms as
Perl itself.