Use the Config tool to change a target's configuration database.

Functions supported include: inspect a tree, read/write values, and import/export entire tree sections.

Usage

config [OPTIONS]

config get <tree path> [--format=json]

Read a value.

config set <tree path> <new value> [<type>]

Write a value.

config move <node path> <new name>

Move a node.

config copy <node path> <new name>

Copy a node.

config delete <tree path>

Delete a node.

config clear <tree path>

Clear a node. Or create a new empty node if it didn't previously exist.

config import <tree path> <file path> [--format=json]

Import config data.

config export <tree path> <file path> [--format=json]

Export config data.

config list

List all config trees.

config rmtree <tree name>

Delete a tree.

config help

Display help.

Options

<tree path>

Path to the tree and node to configure.

<tree name>

Is the name of a tree in the system, but without a path.

<file path>

Path to the file for import/export.

<new value>

String value to write to the config tree.

<type>

Optional, must be bool, int, float, or string. If tool, must be true or false. If unspecified, default type is string.

--format=json

For imports, then properly formatted JSON will be expected. For exports, then the data will be generated as well. It is also possible to specify JSON for the get sub-command.

Tree Paths

A tree path is specified similar to a *nix path. With the beginning slash being optional.

For example:

  @c /a/path/to/somewhere
or
  @c a/path/to/somewhere

The configTree supports multiple trees, a default tree is assigned per user. If the config tool is run as root, then alternative trees can be specified in the path by entering a tree name, then a colon and the value path.

Here's an example using the tree named 'foo' instead of the default tree:

 @c foo:/a/path/to/somewhere

Tree Location

The trees themselves are stored in the file system at:

/legato/systems/current/configTree

The configTree cycles through the extensions, .rock, .paper, and .scissors to differentiate between versions of the tree file. The base file name is the same as the tree.

A listing for /legato/systems/current/configTree where the system tree and the user trees are foo and bar looks like this:

# ls /legato/systems/current/config/ -l
total 32
-rw------- 1 user user  3456 May 12 11:02 bar.rock
-rw------- 1 user user  3456 May  9 11:04 foo.scissors
-rw------- 1 user user 21037 May  9 11:04 system.paper

The system, or root user, has its own tree; each application has a separate tree.

Config Code Samples

To dump a tree, run this to get the default tree for the current user:

config get /

Note: if running as root config get / will return the System Tree

Or to get a specific tree:

# config get foo:/
/
  helloWorld/
    greeted<bool> == true
    ignored<bool> == false

The config tool can also read and write individual values. You can read the value of greeted like this:

# config get /helloWorld/greeted
true

If you want to see everything under helloWorld:

# config get /helloWorld
helloWorld/
  greeted<bool> == true
  ignored<bool> == false

If you want to change the value of ignored:

# config set /helloWorld/ignored true bool

You can check it by running:

# config get /helloWorld/ignored
true

If the config tool is listing a tree, it will display the node name and a / if the current node has children (except for the root node, as the root node does not have a name.)

For leaf nodes, the config tool will display the value type in angle brackets, <>, as well as its name and actual value:

/
  testValues/
    aBoolValue<bool> == true
    aStringValue<string> == This is some text I saved.
    anIntValue<int> == 1024
    afloatValue<float> == 10.24

The tool is designed to be easily used in external scripts. The howToUpgradeAppConfigTree is a good example of using the config tool to backup and restore an app's config tool