cdist/lib/cdist/path.py

import os
import sys
import tempfile

# Hardcoded paths usually not changable
REMOTE_BASE_DIR                 = "/var/lib/cdist"
REMOTE_CONF_DIR                 = os.path.join(REMOTE_BASE_DIR, "conf")
REMOTE_OBJECT_DIR               = os.path.join(REMOTE_BASE_DIR, "object")
REMOTE_TYPE_DIR                 = os.path.join(REMOTE_CONF_DIR, "type")
REMOTE_GLOBAL_EXPLORER_DIR      = os.path.join(REMOTE_CONF_DIR, "explorer")

CODE_HEADER                     = "#!/bin/sh -e\n"
DOT_CDIST                       = ".cdist"
TYPE_PREFIX                     = "__"

def file_to_list(filename):
    """Return list from \n seperated file"""
    if os.path.isfile(filename):
        file_fd = open(filename, "r")
        lines = file_fd.readlines()
        file_fd.close()

        # Remove \n from all lines
        lines = map(lambda s: s.strip(), lines)
    else:
        lines = []

    return lines

# FIXME: self.run_or_fail needs to be elsewhere!
# Exec?

class Path:
    """Class that handles path related configurations"""

    def __init__(self, target_host, base_dir=None):
        # Base and Temp Base 
        if base_dir:
            self.base_dir = base_dir
        else:
            self.base_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), os.pardir, os.pardir))

        self.temp_dir = tempfile.mkdtemp()

        self.conf_dir               = os.path.join(self.base_dir, "conf")
        self.cache_base_dir         = os.path.join(self.base_dir, "cache")
        self.cache_dir              = os.path.join(self.cache_base_dir, target_host)
        self.global_explorer_dir    = os.path.join(self.conf_dir, "explorer")
        self.lib_dir                = os.path.join(self.base_dir, "lib")
        self.manifest_dir           = os.path.join(self.conf_dir, "manifest")
        self.type_base_dir          = os.path.join(self.conf_dir, "type")

        self.out_dir = os.path.join(self.temp_dir, "out")
        os.mkdir(self.out_dir)

        self.global_explorer_out_dir = os.path.join(self.out_dir, "explorer")
        os.mkdir(self.global_explorer_out_dir)

        self.object_base_dir = os.path.join(self.out_dir, "object")

        # Setup binary directory + contents
        self.bin_dir = os.path.join(self.out_dir, "bin")
        os.mkdir(self.bin_dir)
        self.link_type_to_emulator()

        # List of type explorers transferred
        self.type_explorers_transferred = {}

        # objects
        self.objects_prepared = []

        self.remote_user = remote_user

        # Mostly static, but can be overwritten on user demand
        if initial_manifest:
            self.initial_manifest = initial_manifest
        else:
            self.initial_manifest = os.path.join(self.manifest_dir, "init")

    def cleanup(self):
        # Do not use in __del__:
        # http://docs.python.org/reference/datamodel.html#customization
        # "other globals referenced by the __del__() method may already have been deleted 
        # or in the process of being torn down (e.g. the import machinery shutting down)"
        #
        log.debug("Saving" + self.temp_dir + "to " + self.cache_dir)
        # Remove previous cache
        if os.path.exists(self.cache_dir):
            shutil.rmtree(self.cache_dir)
        shutil.move(self.temp_dir, self.cache_dir)


    def remote_mkdir(self, directory):
        """Create directory on remote side"""
        self.run_or_fail(["mkdir", "-p", directory], remote=True)

    def remote_cat(filename):
        """Use cat on the remote side for output"""
        self.run_or_fail(["cat", filename], remote=True)

    def remove_remote_dir(self, destination):
        self.run_or_fail(["rm", "-rf",  destination], remote=True)

    def transfer_dir(self, source, destination):
        """Transfer directory and previously delete the remote destination"""
        self.remove_remote_dir(destination)
        self.run_or_fail(["scp", "-qr", source, 
                                self.remote_user + "@" + 
                                self.target_host + ":" + 
                                destination])

    def transfer_file(self, source, destination):
        """Transfer file"""
        self.run_or_fail(["scp", "-q", source, 
                                self.remote_user + "@" +
                                self.target_host + ":" +
                                destination])

    def global_explorer_output_path(self, explorer):
        """Returns path of the output for a global explorer"""
        return os.path.join(self.global_explorer_out_dir, explorer)

    def type_explorer_output_dir(self, cdist_object):
        """Returns and creates dir of the output for a type explorer"""
        dir = os.path.join(self.object_dir(cdist_object), "explorer")
        if not os.path.isdir(dir):
            os.mkdir(dir)

        return dir

    def remote_global_explorer_path(self, explorer):
        """Returns path to the remote explorer"""
        return os.path.join(REMOTE_GLOBAL_EXPLORER_DIR, explorer)

    def list_global_explorers(self):
        """Return list of available explorers"""
        return os.listdir(self.global_explorer_dir)

    def list_type_explorers(self, type):
        """Return list of available explorers for a specific type"""
        dir = self.type_dir(type, "explorer")
        if os.path.isdir(dir):
            list = os.listdir(dir)
        else:
            list = []

        log.debug("Explorers for %s in %s: %s", type, dir, list)

        return list

    def list_types(self):
        return os.listdir(self.type_base_dir)

    def list_object_paths(self, starting_point):
        """Return list of paths of existing objects"""
        object_paths = []

        for content in os.listdir(starting_point):
            full_path = os.path.join(starting_point, content)
            if os.path.isdir(full_path):
                object_paths.extend(self.list_object_paths(starting_point = full_path))

            # Directory contains .cdist -> is an object
            if content == DOT_CDIST:
                object_paths.append(starting_point)

        return object_paths

    # FIXME
    def get_type_from_object(self, cdist_object):
        """Returns the first part (i.e. type) of an object"""
        return cdist_object.split(os.sep)[0]

    def get_object_id_from_object(self, cdist_object):
        """Returns everything but the first part (i.e. object_id) of an object"""
        return os.sep.join(cdist_object.split(os.sep)[1:])

    def object_dir(self, cdist_object):
        """Returns the full path to the object (including .cdist)"""
        return os.path.join(self.object_base_dir, cdist_object, DOT_CDIST)

    def remote_object_dir(self, cdist_object):
        """Returns the remote full path to the object (including .cdist)"""
        return os.path.join(REMOTE_OBJECT_DIR, cdist_object, DOT_CDIST)

    def object_parameter_dir(self, cdist_object):
        """Returns the dir to the object parameter"""
        return os.path.join(self.object_dir(cdist_object), "parameter")

    def remote_object_parameter_dir(self, cdist_object):
        """Returns the remote dir to the object parameter"""
        return os.path.join(self.remote_object_dir(cdist_object), "parameter")

    def object_code_paths(self, cdist_object):
        """Return paths to code scripts of object"""
        return [os.path.join(self.object_dir(cdist_object), "code-local"),
                  os.path.join(self.object_dir(cdist_object), "code-remote")]

    def list_objects(self):
        """Return list of existing objects"""

        objects = []
        if os.path.isdir(self.object_base_dir):
            object_paths = self.list_object_paths(self.object_base_dir)

            for path in object_paths:
                objects.append(os.path.relpath(path, self.object_base_dir))

        return objects

    def type_dir(self, type, *args):
        """Return directory the type"""
        return os.path.join(self.type_base_dir, type, *args)

    def remote_type_explorer_dir(self, type):
        """Return remote directory that holds the explorers of a type"""
        return os.path.join(REMOTE_TYPE_DIR, type, "explorer")

    def transfer_object_parameter(self, cdist_object):
        """Transfer the object parameter to the remote destination"""
        # Create base path before using mkdir -p
        self.remote_mkdir(self.remote_object_parameter_dir(cdist_object))

        # Synchronise parameter dir afterwards
        self.transfer_dir(self.object_parameter_dir(cdist_object), 
                                self.remote_object_parameter_dir(cdist_object))

    def transfer_global_explorers(self):
        """Transfer the global explorers"""
        self.remote_mkdir(REMOTE_GLOBAL_EXPLORER_DIR)
        self.transfer_dir(self.global_explorer_dir, REMOTE_GLOBAL_EXPLORER_DIR)

    def transfer_type_explorers(self, type):
        """Transfer explorers of a type, but only once"""
        if type in self.type_explorers_transferred:
            log.debug("Skipping retransfer for explorers of %s", type)
            return
        else:
            # Do not retransfer
            self.type_explorers_transferred[type] = 1

        src = self.type_dir(type, "explorer")
        remote_base = os.path.join(REMOTE_TYPE_DIR, type)
        dst = self.remote_type_explorer_dir(type)

        # Only continue, if there is at least the directory
        if os.path.isdir(src):
            # Ensure that the path exists
            self.remote_mkdir(remote_base)
            self.transfer_dir(src, dst)


    def link_type_to_emulator(self):
        """Link type names to cdist-type-emulator"""
        source = os.path.abspath(sys.argv[0])
        for type in self.list_types():
            destination = os.path.join(self.bin_dir, type)
            log.debug("Linking %s to %s", source, destination)
            os.symlink(source, destination)