Api Docs

Implement backup, verify, restore for bun.

class bun.backup.Bun(ctx, timestamp)

Backup path(s) based on configuration.

backup(target)

Foreach target spec, backup the specified paths (if they exist). :param target: a list of one or more target spec names

check(directory)

Foreach tarball in directory verify check sums

Parameters:directory – directory containing tarballs to validate checksums of.

check_sum(spec_name)

return a shell command to create the specified checksum of the created tarball. :param spec_name: use this as the start of the tarball name :return: the checksum pipeline command to create the checksum file

compress(output='-')

Generate the (optional) compress command as part of the backup pipeline :param output: optionally specify the output directly - defaults to stdout (‘-‘) :return: the compress command

only_existing(paths)

Return a list of elements from paths which exist on the filesystem (respects start_dir).

paths(target)

generator which yields the list of paths to process :param target: specifies the list of spec sets to return :return: (yield) a tuple: the (spec_name, path(s) list) to be backed up

pipeline(spec_name, paths)

return a shell command to backup the directory tree at path :param spec_name: use this as the start of the tarball name :param paths: list of paths to backup in one go :return: the tar pipeline command to tar’up the directory tree under path

pretend(target)

As per backup, but don’t check if paths exist, and only echo the tar command (not run it) :param target: is a list of one or more target spec names

redirect(spec_name, extra_suffix='')

Generates the shell output redirect to create a tarball (or checksum of that tarball) :param spec_name: unique name prefix for a tarball/checksum file :param extra_suffix: optional suffix to add to the generated redirect/path :return: a redirect to path string suitable to store the generated tarball

restore(location, target)

extract the tarballs belonging to target in bun.backup_dir to location :param location: is the point where the tarballs will be extracted to :param target: is the spec name of the target(s) to extract

tar(paths, output='-')

Generate a tar command :param paths: list of paths to backup in one go :param output: optionally specify the output directly - defaults to stdout (‘-‘) :return: the tar command

tarball(spec_name, extra_suffix='')

Return the full path name of a tarball (or checksum of that tarball) based on spec_name :param spec_name: unique name prefix for a tarball/checksum file :param extra_suffix: optional suffix to add to the generated path name :return: a (string) tarball file name (fully qualified)

verify(target)

Foreach tarball in the target spec(s) verify the check sums

Parameters:target – spec name to verify

Implements configuration discovery for bun

bun.config.add_packages(bun_config, directory)

if directory exists then merge all configuration into the bun_config dict

Parameters:

• bun_config – existing dict config to merge new config into
• directory – directory which holds config to merge

Returns:

merged dict of the original config plus config from directory

bun.config.settings()

generate a consolidated set of configuration for bun - if BUN_CONFIG_DIR is set then only read configuration from there; otherwise read config from the directory /etc/bun and the file /etc/oam/conf.d/bun.yaml (if it exists)

Returns:a dict holding bun configuration

bun.config.collection()

Return an invoke collection for bun

bun.config.config()

dump configuration in effect to the console

Parameters:ctx – invoke context

Implementation of builtin defaults for bun

DEFAULT_CONFIG = {
    'bun': {
        'backup_dir': '/backup',         # location we backup to
        'checksum': 'sha256sum',         # checksum program to use - leave empty for no checksum generation
        'compress': 'xz -9',             # compression command to use - leave empty for no compression; also see suffix
        'default': ['homes'],            # default 'spec set(s)' to backup; see: spec dict later on
        'nice': 'nice ionice -c3',       # nice'ness to use - leave empty for no nice'ness
        'suffix': 'xz',                  # add this suffix to the generated tarball; see compress program earlier
        'start_dir': '/',                # paths to backup are relative to this dir
        'tar_opts': [                    # options to pass to tar
            '--exclude-caches',
            '--exclude-vcs',
            '--exclude-vcs-ignores',
            '--one-file-system'
            ],
        'timespec': '%Y%m%d-%H%M%S',     # alt: '%Y%m%d'
        'spec': {                        # directory sets that can be backed up
            'homes': [                   # unique token to identify the set (the reserved token 'all' means all sets)
                'home',                  # list of directories/files to backup relative to the start_dir
                'root'
                ]
        }
    },
    'run': {                             # invoke default overrides
        'echo': True
    }
}

bun.defaults.settings()

Returns the unaltered default built-in configuration for bun

bun.defaults.defaults()

dump the default settings to the console :param ctx: :return:

Implement script entry point for bun.

class bun.main.BunConfig(overrides=None, defaults=None, system_prefix=None, user_prefix=None, project_location=None, runtime_path=None, lazy=False)

Specialisation of Config for bun.

class bun.main.BunProgram(version=None, namespace=None, name=None, binary=None, loader_class=None, executor_class=None, config_class=None)

Specialisation of Program for bun.