NAME
Config::Model::Loader - Load serialized data into config tree
VERSION
version 2.154
SYNOPSIS
use Config::Model;
# define configuration tree object
my $model = Config::Model->new;
$model->create_config_class(
name => "Foo",
element => [
[qw/foo bar/] => {
type => 'leaf',
value_type => 'string'
},
]
);
$model ->create_config_class (
name => "MyClass",
element => [
[qw/foo bar/] => {
type => 'leaf',
value_type => 'string'
},
hash_of_nodes => {
type => 'hash', # hash id
index_type => 'string',
cargo => {
type => 'node',
config_class_name => 'Foo'
},
},
[qw/lista listb/] => {
type => 'list',
cargo => {type => 'leaf',
value_type => 'string'
}
},
],
) ;
my $inst = $model->instance(root_class_name => 'MyClass' );
my $root = $inst->config_root ;
# put data
my $steps = 'foo=FOO hash_of_nodes:fr foo=bonjour -
hash_of_nodes:en foo=hello
! lista=foo,bar lista:2=baz
listb:0=foo listb:1=baz';
$root->load( steps => $steps );
my $s = $root->fetch_element_value('foo'); # => is 'FOO'
$s = $root->grab_value('hash_of_nodes:en foo'); # => is 'hello'
$s = $root->grab_value('lista:1'); # => is 'bar'
$s = $root->grab_value('lista:2'); # => is 'baz'
# delete some data
$root->load( steps => 'lista~2' );
$s = $root->grab_value('lista:2'); # => is undef
# append some data
$root->load( steps => q!hash_of_nodes:en foo.=" world"! );
$s = $root->grab_value('hash_of_nodes:en foo'); # => is 'hello world'
DESCRIPTION
This module is used directly by Config::Model::Node to load serialized configuration data into the configuration tree.
Serialized data can be written by the user or produced by Config::Model::Dumper while dumping data from a configuration tree.
CONSTRUCTOR
new
The constructor should be used only by Config::Model::Node.
Parameters:
- start_node
-
node ref of the root of the tree (of sub-root) to start the load from. Stored as a weak reference.
load string syntax
The string is made of the following items (also called actions
) separated by spaces. These actions can be divided in 4 groups:
navigation: moving up and down the configuration tree.
list and hash operation: select, add or delete hash or list item (also known as
id
items)leaf operation: select, modify or delecte leaf value
annotation: modify or delete configuration annotation (aka comment)
navigation
- -
-
Go up one node
- !
-
Go to the root node of the configuration tree.
- xxx
-
Go down using
xxx
element. (Fornode
type element) - /xxx
-
Go up until the element
xxx
is found. This search can be combined with one of the command specified below, e.g/a_string="foo bar"
list and hash operation
- xxx:yy
-
Go down using
xxx
element and idyy
(Forhash
orlist
element withnode
cargo_type). Literal\n
are replaced by real\n
(LF in Unix). - xxx:.foreach_match(yy) or xxx:~yy
-
Go down using
xxx
element and loop over the ids that match the regex specified byyy
. (Forhash
).For instance, with
OpenSsh
model, you could doHost:~"/.*.debian.org/" user='foo-guest'
to set "foo-user" users for all your debian accounts.
The leading and trailing '/' may be omitted. Be sure to surround the regexp with double quote if space are embedded in the regex.
Note that the loop ends when the load command goes above the element where the loop is executed. For instance, the instruction below tries to execute
DX=BV
andint_v=9
for all elements ofstd_id
hash:std_id:~/^\w+$/ DX=Bv int_v=9
In the examples below only
DX=BV
is executed by the loop:std_id:~/^\w+$/ DX=Bv - int_v=9 std_id:~/^\w+$/ DX=Bv ! int_v=9
The loop is done on all elements of the hash when no value is passed after "
:~
" (mnemonic: an empty regexp matches any value). - xxx:.rm(yy) or xxx:-yy
-
Delete item referenced by
xxx
element and idyy
. For a list, this is equivalent tosplice xxx,yy,1
. This command does not go down in the tree (since it has just deleted the element). I.e. a '-
' is generally not needed afterwards. - xxx:.rm_value(yy) or xxx:-=yy
-
Remove the element whose value is
yy
. For list or hash of leaves. Does not not complain if the value to delete is not found. - xxx:..rm_match(yy) or xxx:-~/yy/
-
Remove the element whose value matches
yy
. For list or hash of leaves. Does not not complain if no value were deleted. - xxx:.substitute(/yy/zz/) or xxx:=~s/yy/zz/
-
Substitute a value with another. Perl switches can be used(e.g.
xxx:=~s/yy/zz/gi
) - xxx:<yy or xxx:.push(yy)
-
Push
yy
value onxxx
list - xxx:>yy or xxx:.unshift(yy)
-
Unshift
yy
value onxxx
list - xxx:@ or xxx:.sort
-
Sort the list
- xxx:.insert_at(yy,zz)
-
Insert
zz
value onxxx
list before indexyy
. - xxx:.insert_before(yy,zz)
-
Insert
zz
value onxxx
list before valueyy
. - xxx:.insert_before(/yy/,zz)
-
Insert
zz
value onxxx
list before value matchingyy
. - xxx:.insort(zz)
-
Insert
zz
value onxxx
list so that existing alphanumeric order is preserved. - xxx:.insort(zz)
-
For hash element containing nodes: creates a new hash element with
zz
key onxxx
hash so that existing alphanumeric order of keys is preserved. Note that all keys are sorted once this instruction is called. Following instructions are applied on the created element. I.e. putting key order aside,xxx:.insort(zz)
has the same effect asxxx:zz
instruction. - xxx:.insort(zz,vv)
-
For hash element containing leaves: creates a new hash element with
zz
key and assing valuevv
so that existing alphanumeric order of keys is preserved. Note that all keys are sorted once this instruction is called. Putting key order aside,xxx:.insort(zz,vv)
has the same effect asxxx:zz=vv
instruction. - xxx:.ensure(zz,...)
-
Ensure that list
xxx
contains valuezz
. If valuezz
is already stored inxxx
list, this function does nothing. In the other case, valuezz
is inserted in alphabetical order. This function accepts a list of values separated by a comma. - xxx:=z1,z2,z3
-
Set list element
xxx
to listz1,z2,z3
. Use,,
for undef values, and""
for empty values.I.e, for a list
('a',undef,'','c')
, usea,,"",c
. - xxx:yy=zz
-
For
hash
element containingleaf
cargo_type. Set the leaf identified by keyyy
to valuezz
.Using
xxx:~/yy/=zz
is also possible. - xxx:.copy(yy,zz)
-
copy item
yy
inzz
(hash or list). - xxx:.rename(yy,zz)
-
rename item
yy
inzz
(hash). - xxx:.move(yy,zz)
-
Alias to rename.
- xxx:.json("path/to/file.json/foo/bar")
-
Store
bar
content in array or hash. This should be used to store hash or list of values.You may store deep data structure. In this case, make sure that the structure of the loaded data matches the structure of the model. This won't happen by chance.
- xxx:.clear
-
Clear the hash or list.
leaf operation
- xxx=zz
-
Set element
xxx
to valueyy
. load also accepts to set elements with a quoted string. (Forleaf
element) Literal\n
are replaced by real\n
(LF in Unix). Literal\\
are replaced by\
.For instance
foo="a quoted string"
orfoo="\"bar\" and \"baz\""
. - xxx=~s/foo/bar/
-
Apply the substitution to the value of xxx.
s/foo/bar/
is the standard Perls
substitution pattern.Patterns with white spaces must be surrounded by quotes:
xxx=~"s/foo bar/bar baz/"
Perl pattern modifiers are accepted
xxx=~s/FOO/bar/i
- xxx~
-
Undef element
xxx
- xxx.=zzz
-
Appends
zzz
value to current value (valid forleaf
elements). - xxx=.file(yyy)
-
Store the content of file
yyy
in elementxxx
.Store STDIn in value xxx when
yyy
is '-'. - xxx=.json(path/to/data.json/foo/bar)
-
Open file
data.json
and store value from JSON data extracted withfoo/bar
subpath.For instance, if
data.json
contains:{ "foo": { "bar": 42 } }
The instruction
baz=.json(data.json/foo/bar)
stores42
inbaz
element. - xxx=.yaml(path/to/data.yaml/0/foo/bar)
-
Open file
data.yaml
and store value from YAML data extracted with0/foo/bar
subpath.Since a YAML file can contain several documents (separated by
---
lines, the subpath must begin with a number to select the document containing the required value.For instance, if
data.yaml
contains:--- foo: bar: 42
The instruction
baz=.yaml(data.yaml/0/foo/bar)
stores42
inbaz
element. - xxx=.env(yyy)
-
Store the content of environment variable
yyy
in elementxxx
.
annotation
- xxx#zzz or xxx:yyy#zzz
-
Element annotation. Can be quoted or not quoted. Note that annotations are always placed at the end of an action item.
I.e.
foo#comment
,foo:bar#comment
orfoo:bar=baz#comment
are valid.foo#comment:bar
is not valid.
Quotes
You can surround indexes and values with single or double quotes. E.g.:
a_string='"foo" and "bar"'
Single quotes were added in version 2.153.
Examples
You can use cme to modify configuration with cme modify
command.
For instance, if Config::Model::Ssh is installed, you can run:
cme modify ssh 'ControlMaster=auto ControlPath="~/.ssh/master-%r@%n:%p"'
To delete Host *
entry:
cme modify ssh 'Host:-"*"'
To specify 2 Host
with a single command:
cme modify ssh 'Host:"foo* bar*" ForwardX11=yes HostName="foo.com" - Host:baz HostName="baz.com"'
Note the '-
' used to go up one node before "Host:baz
". In this case, "up one node" leads to the "root node", so "!
" could also be used instead of "-
":
cme modify ssh 'Host:"foo* bar*" ForwardX11=yes HostName="foo.com" ! Host:baz HostName="baz.com"'
Let's modify now the host name of using a .org
domain instead of .com
. The :~
operator uses a regexp to loop over several Host entries:
cme modify ssh 'Host:~/ba[rz]/ HostName=~s/.com$/.org/'
Now that ssh config is mucked up with dummy entries, let's clean up:
cme modify ssh 'Host:-"baz" Host:-"foo* bar*"'
Methods
load
Load data into the node tree (from the node passed with node
) and fill values as we go following the instructions passed with steps
. (steps
can also be an array ref).
Parameters are:
- steps (or step)
-
A string or an array ref containing the steps to load. See "load string syntax" in above for a description of the string.
- check
-
Whether to check values while loading. Either
yes
(default),no
orskip
. Bad values are discarded whencheck
is set toskip
. - caller_is_root
-
Change the target of the
!
command: when set, the!
command go to caller node instead of going to root node. (default is false)
AUTHOR
Dominique Dumont, (ddumont at cpan dot org)
SEE ALSO
Config::Model,Config::Model::Node,Config::Model::Dumper
AUTHOR
Dominique Dumont
COPYRIGHT AND LICENSE
This software is Copyright (c) 2005-2022 by Dominique Dumont.
This is free software, licensed under:
The GNU Lesser General Public License, Version 2.1, February 1999