Add validate_augeas function

1 files changed, 70 insertions, 0 deletions

diff --git a/lib/puppet/parser/functions/validate_augeas.rb b/lib/puppet/parser/functions/validate_augeas.rb
new file mode 100644
index 0000000..01a2e91
--- /dev/null
+++ b/lib/puppet/parser/functions/validate_augeas.rb
@@ -0,0 +1,70 @@
+module Puppet::Parser::Functions
+  newfunction(:validate_augeas, :doc => <<-'ENDHEREDOC') do |args|
+    Perform validation of a string using an Augeas lens
+    The first argument of this function should be a string to
+    test, and the second argument should be the name of the Augeas lens to use.
+    If Augeas fails to parse the string with the lens, the compilation will
+    abort with a parse error.
+
+    A third argument can be specified, listing paths which should
+    not be found in the file. The `$file` variable points to the location
+    of the temporary file being tested in the Augeas tree.
+
+    For example, if you want to make sure your passwd content never contains
+    a user `foo`, you could write:
+
+        validate_augeas($passwdcontent, 'Passwd.lns', ['$file/foo'])
+
+    Or if you wanted to ensure that no users used the '/bin/barsh' shell,
+    you could use:
+    
+        validate_augeas($passwdcontent, 'Passwd.lns', ['$file/*[shell="/bin/barsh"]']
+
+    If a fourth argument is specified, this will be the error message raised and
+    seen by the user.
+
+    A helpful error message can be returned like this:
+
+        validate_augeas($sudoerscontent, 'Sudoers.lns', [], 'Failed to validate sudoers content with Augeas')
+
+    ENDHEREDOC
+    if (args.length < 2) or (args.length > 4) then
+      raise Puppet::ParseError, ("validate_augeas(): wrong number of arguments (#{args.length}; must be 2, 3, or 4)")
+    end
+
+    msg = args[3] || "validate_augeas(): Failed to validate content against #{args[1].inspect}"
+
+    require 'augeas'
+    aug = Augeas::open(nil, nil, Augeas::NO_MODL_AUTOLOAD)
+
+    content = args[0]
+
+    # Test content in a temporary file
+    tmpfile = Tempfile.new("validate_augeas")
+    tmpfile.write(content)
+    tmpfile.close
+
+    # Check for syntax
+    lens = args[1]
+    aug.transform(
+      :lens => lens,
+      :name => 'Validate_augeas',
+      :incl => tmpfile.path
+    )
+    aug.load!
+
+    unless aug.match("/augeas/files#{tmpfile.path}//error").empty?
+      error = aug.get("/augeas/files#{tmpfile.path}//error/message")
+      msg += " with error: #{error}"
+      raise Puppet::ParseError, (msg)
+    end
+
+    # Launch unit tests
+    tests = args[2] || []
+    aug.defvar('file', "/files#{tmpfile.path}")
+    tests.each do |t|
+      msg += " testing path #{t}"
+      raise Puppet::ParseError, (msg) unless aug.match(t).empty?
+    end
+  end
+end