Augeas

Create a new Augeas instance and return it.

Use root as the filesystem root. If root is nil, use the value of the environment variable AUGEAS_ROOT. If that doesn’t exist either, use “/”.

loadpath is a colon-spearated list of directories that modules should be searched in. This is in addition to the standard load path and the directories in AUGEAS_LENS_LIB

flags is a bitmask (see enum aug_flags)

When a block is given, the Augeas instance is passed as the only argument into the block and closed when the block exits. In that case, the return value of the block is the return value of open. With no block, the Augeas instance is returned.

# File lib/augeas.rb, line 47
def self.open(root = nil, loadpath = nil, flags = NONE, &block)
    aug = open3(root, loadpath, flags)
    if block_given?
        begin
            rv = yield aug
            return rv
        ensure
            aug.close
        end
    else
        return aug
    end
end

Clear the path, i.e. make its value nil

# File lib/augeas.rb, line 76
def clear(path)
    set_internal(path, nil)
end

Clear all transforms under /augeas/load. If load is called right after this, there will be no files under /files

# File lib/augeas.rb, line 95
def clear_transforms
    rm("/augeas/load/*")
end

Clear multiple nodes values in one operation. Find or create a node matching sub by interpreting sub as a path expression relative to each node matching base. If sub is ‘.’, the nodes matching base will be modified.

# File lib/augeas.rb, line 83
def clearm(base, sub)
    setm(base, sub, nil)
end

Get path expression context (from /augeas/context)

# File lib/augeas.rb, line 138
def context
  get('/augeas/context')
end

Set path expression context to path (in /augeas/context)

# File lib/augeas.rb, line 133
def context=(path)
  set_internal('/augeas/context', path)
end

The same as load, but raises Augeas::Error if loading fails

# File lib/augeas.rb, line 128
def load!
    raise Augeas::Error unless load
end

The same as save, but raises Augeas::Error if saving fails

# File lib/augeas.rb, line 123
def save!
    raise Augeas::Error unless save
end

Set one or multiple elemens to path. Multiple elements are mainly sensible with a path like …/array, since this will append all elements.

# File lib/augeas.rb, line 64
def set(path, *values)
    values.flatten.each { |v| set_internal(path, v) }
end

The same as set, but raises Augeas::Error if setting fails

# File lib/augeas.rb, line 69
def set!(path, *values)
    values.flatten.each do |v|
        raise Augeas::Error unless set_internal(path, v)
    end
end

Create the path with empty value if it doesn’t exist

# File lib/augeas.rb, line 88
def touch(path)
    set_internal(path, nil) if match(path).empty?
end

Add a transform under /augeas/load

The HASH can contain the following entries

• :lens - the name of the lens to use

• :name - a unique name; use the module name of the LENS when omitted

• :incl - a list of glob patterns for the files to transform

• :excl - a list of the glob patterns to remove from the list that matches :INCL

# File lib/augeas.rb, line 106
def transform(hash)
    lens = hash[:lens]
    name = hash[:name]
    incl = hash[:incl]
    excl = hash[:excl]
    raise ArgumentError, "No lens specified" unless lens
    raise ArgumentError, "No files to include" unless incl
    lens = "#{lens}.lns" unless lens.include? '.'
    name = lens.split(".")[0].sub("@", "") unless name

    xfm = "/augeas/load/#{name}/"
    set(xfm + "lens", lens)
    set(xfm + "incl[last()+1]", incl)
    set(xfm + "excl[last()+1]", excl) if excl
end