sirosen/SALVE

#!/usr/bin/python

from __future__ import print_function

import os
import sys

import salve

from salve import paths
from salve.context import FileContext
from salve.exceptions import SALVEException
from salve.block import ManifestBlock
from salve.filesys import ConcreteFilesys


def run_on_manifest(root_manifest, args):
    """
    Given a manifest file, loads SALVEConfig, parses and expands the
    root manifest, then executes the actions defined by that manifest.

    Args:
        @root_manifest
        The manifest at the root of the manifest tree, and starting
        point for manifest execution.
        @args
        The options, as parsed from the commandline.
    """
    root_dir = paths.containing_dir(root_manifest)
    if args.directory and not args.v3_relpath:
        root_dir = os.path.abspath(args.directory)

    # root_block is a synthetic manifest block containing the root
    # manifest
    root_block = ManifestBlock(FileContext('no such file'),
                               source=root_manifest)
    root_block.expand_blocks(root_dir, args.v3_relpath)

    root_action = root_block.compile()
    root_action(ConcreteFilesys())


def main(args):
    """
    The main method of SALVE deployment. Runs the core program end-to-end.
    """
    try:
        run_on_manifest(args.manifest, args)
    except SALVEException as e:
        salve.logger.error(str(e.file_context) + ': ' + e.message)
        # Normally, sys.exit() is to be avoided, but main() is only
        # invoked if salve is running as a script, and we want to give
        # the right exit status for commandline usage
        sys.exit(1)