from __future__ import absolute_import from __future__ import unicode_literals import codecs import logging import operator import os import sys from collections import namedtuple import six import yaml from ..const import COMPOSEFILE_VERSIONS from .errors import CircularReference from .errors import ComposeFileNotFound from .errors import ConfigurationError from .interpolation import interpolate_environment_variables from .sort_services import get_service_name_from_net from .sort_services import sort_service_dicts from .types import parse_extra_hosts from .types import parse_restart_spec from .types import VolumeFromSpec from .types import VolumeSpec from .validation import validate_against_fields_schema from .validation import validate_against_service_schema from .validation import validate_extends_file_path from .validation import validate_top_level_object from .validation import validate_top_level_service_objects DOCKER_CONFIG_KEYS = [ 'cap_add', 'cap_drop', 'cgroup_parent', 'command', 'cpu_quota', 'cpu_shares', 'cpuset', 'detach', 'devices', 'dns', 'dns_search', 'domainname', 'entrypoint', 'env_file', 'environment', 'extra_hosts', 'hostname', 'image', 'ipc', 'labels', 'links', 'mac_address', 'mem_limit', 'memswap_limit', 'net', 'pid', 'ports', 'privileged', 'read_only', 'restart', 'security_opt', 'stdin_open', 'stop_signal', 'tty', 'user', 'volume_driver', 'volumes', 'volumes_from', 'working_dir', ] ALLOWED_KEYS = DOCKER_CONFIG_KEYS + [ 'build', 'container_name', 'dockerfile', 'expose', 'external_links', 'logging', ] DOCKER_VALID_URL_PREFIXES = ( 'http://', 'https://', 'git://', 'github.com/', 'git@', ) SUPPORTED_FILENAMES = [ 'docker-compose.yml', 'docker-compose.yaml', ] DEFAULT_OVERRIDE_FILENAME = 'docker-compose.override.yml' log = logging.getLogger(__name__) class ConfigDetails(namedtuple('_ConfigDetails', 'working_dir config_files')): """ :param working_dir: the directory to use for relative paths in the config :type working_dir: string :param config_files: list of configuration files to load :type config_files: list of :class:`ConfigFile` """ class ConfigFile(namedtuple('_ConfigFile', 'filename config')): """ :param filename: filename of the config file :type filename: string :param config: contents of the config file :type config: :class:`dict` """ @classmethod def from_filename(cls, filename): return cls(filename, load_yaml(filename)) def get_service_dicts(self, version): return self.config if version == 1 else self.config.get('services', {}) class Config(namedtuple('_Config', 'version services volumes')): """ :param version: configuration version :type version: int :param services: List of service description dictionaries :type services: :class:`list` :param volumes: List of volume description dictionaries :type volumes: :class:`list` """ class ServiceConfig(namedtuple('_ServiceConfig', 'working_dir filename name config')): @classmethod def with_abs_paths(cls, working_dir, filename, name, config): if not working_dir: raise ValueError("No working_dir for ServiceConfig.") return cls( os.path.abspath(working_dir), os.path.abspath(filename) if filename else filename, name, config) def find(base_dir, filenames): if filenames == ['-']: return ConfigDetails( os.getcwd(), [ConfigFile(None, yaml.safe_load(sys.stdin))]) if filenames: filenames = [os.path.join(base_dir, f) for f in filenames] else: filenames = get_default_config_files(base_dir) log.debug("Using configuration files: {}".format(",".join(filenames))) return ConfigDetails( os.path.dirname(filenames[0]), [ConfigFile.from_filename(f) for f in filenames]) def get_config_version(config_details): def get_version(config): if config.config is None: return 1 version = config.config.get('version', 1) if isinstance(version, dict): # in that case 'version' is probably a service name, so assume # this is a legacy (version=1) file version = 1 return version main_file = config_details.config_files[0] validate_top_level_object(main_file) version = get_version(main_file) for next_file in config_details.config_files[1:]: validate_top_level_object(next_file) next_file_version = get_version(next_file) if version != next_file_version and next_file_version is not None: raise ConfigurationError( "Version mismatch: main file {0} specifies version {1} but " "extension file {2} uses version {3}".format( main_file.filename, version, next_file.filename, next_file_version ) ) return version def get_default_config_files(base_dir): (candidates, path) = find_candidates_in_parent_dirs(SUPPORTED_FILENAMES, base_dir) if not candidates: raise ComposeFileNotFound(SUPPORTED_FILENAMES) winner = candidates[0] if len(candidates) > 1: log.warn("Found multiple config files with supported names: %s", ", ".join(candidates)) log.warn("Using %s\n", winner) return [os.path.join(path, winner)] + get_default_override_file(path) def get_default_override_file(path): override_filename = os.path.join(path, DEFAULT_OVERRIDE_FILENAME) return [override_filename] if os.path.exists(override_filename) else [] def find_candidates_in_parent_dirs(filenames, path): """ Given a directory path to start, looks for filenames in the directory, and then each parent directory successively, until found. Returns tuple (candidates, path). """ candidates = [filename for filename in filenames if os.path.exists(os.path.join(path, filename))] if not candidates: parent_dir = os.path.join(path, '..') if os.path.abspath(parent_dir) != os.path.abspath(path): return find_candidates_in_parent_dirs(filenames, parent_dir) return (candidates, path) def load(config_details): """Load the configuration from a working directory and a list of configuration files. Files are loaded in order, and merged on top of each other to create the final configuration. Return a fully interpolated, extended and validated configuration. """ version = get_config_version(config_details) if version not in COMPOSEFILE_VERSIONS: raise ConfigurationError('Invalid config version provided: {0}'.format(version)) processed_files = [] for config_file in config_details.config_files: processed_files.append( process_config_file(config_file, version=version) ) config_details = config_details._replace(config_files=processed_files) if version == 1: service_dicts = load_services( config_details.working_dir, config_details.config_files, version ) volumes = {} elif version == 2: config_files = [ ConfigFile(f.filename, f.config.get('services', {})) for f in config_details.config_files ] service_dicts = load_services( config_details.working_dir, config_files, version ) volumes = load_volumes(config_details.config_files) return Config(version, service_dicts, volumes) def load_volumes(config_files): volumes = {} for config_file in config_files: for name, volume_config in config_file.config.get('volumes', {}).items(): if volume_config is None: volumes.update({name: {}}) continue volumes.update({name: volume_config}) external = volume_config.get('external') if external: if len(volume_config.keys()) > 1: raise ConfigurationError( 'Volume {0} declared as external but specifies' ' additional attributes ({1}). '.format( name, ', '.join([k for k in volume_config.keys() if k != 'external']) ) ) if isinstance(external, dict): volume_config['external_name'] = external.get('name') else: volume_config['external_name'] = name return volumes def load_services(working_dir, config_files, version): def build_service(filename, service_name, service_dict): service_config = ServiceConfig.with_abs_paths( working_dir, filename, service_name, service_dict) resolver = ServiceExtendsResolver(service_config, version) service_dict = process_service(resolver.run()) # TODO: move to validate_service() validate_against_service_schema(service_dict, service_config.name, version) validate_paths(service_dict) service_dict = finalize_service(service_config._replace(config=service_dict)) service_dict['name'] = service_config.name return service_dict def build_services(config_file): return sort_service_dicts([ build_service(config_file.filename, name, service_dict) for name, service_dict in config_file.config.items() ]) def merge_services(base, override): all_service_names = set(base) | set(override) return { name: merge_service_dicts_from_files( base.get(name, {}), override.get(name, {}), version) for name in all_service_names } config_file = config_files[0] for next_file in config_files[1:]: config = merge_services(config_file.config, next_file.config) config_file = config_file._replace(config=config) return build_services(config_file) def process_config_file(config_file, version, service_name=None): service_dicts = config_file.get_service_dicts(version) validate_top_level_service_objects( config_file.filename, service_dicts ) interpolated_config = interpolate_environment_variables(service_dicts) if version == 2: processed_config = dict(config_file.config) processed_config.update({'services': interpolated_config}) if version == 1: processed_config = interpolated_config validate_against_fields_schema( processed_config, config_file.filename, version ) if service_name and service_name not in processed_config: raise ConfigurationError( "Cannot extend service '{}' in {}: Service not found".format( service_name, config_file.filename)) return config_file._replace(config=processed_config) class ServiceExtendsResolver(object): def __init__(self, service_config, version, already_seen=None): self.service_config = service_config self.working_dir = service_config.working_dir self.already_seen = already_seen or [] self.version = version @property def signature(self): return self.service_config.filename, self.service_config.name def detect_cycle(self): if self.signature in self.already_seen: raise CircularReference(self.already_seen + [self.signature]) def run(self): self.detect_cycle() if 'extends' in self.service_config.config: service_dict = self.resolve_extends(*self.validate_and_construct_extends()) return self.service_config._replace(config=service_dict) return self.service_config def validate_and_construct_extends(self): extends = self.service_config.config['extends'] if not isinstance(extends, dict): extends = {'service': extends} config_path = self.get_extended_config_path(extends) service_name = extends['service'] extended_file = process_config_file( ConfigFile.from_filename(config_path), version=self.version, service_name=service_name ) service_config = extended_file.config[service_name] return config_path, service_config, service_name def resolve_extends(self, extended_config_path, service_dict, service_name): resolver = ServiceExtendsResolver( ServiceConfig.with_abs_paths( os.path.dirname(extended_config_path), extended_config_path, service_name, service_dict), self.version, already_seen=self.already_seen + [self.signature]) service_config = resolver.run() other_service_dict = process_service(service_config) validate_extended_service_dict( other_service_dict, extended_config_path, service_name, ) return merge_service_dicts( other_service_dict, self.service_config.config, self.version) def get_extended_config_path(self, extends_options): """Service we are extending either has a value for 'file' set, which we need to obtain a full path too or we are extending from a service defined in our own file. """ filename = self.service_config.filename validate_extends_file_path( self.service_config.name, extends_options, filename) if 'file' in extends_options: return expand_path(self.working_dir, extends_options['file']) return filename def resolve_environment(service_dict): """Unpack any environment variables from an env_file, if set. Interpolate environment values if set. """ env = {} for env_file in service_dict.get('env_file', []): env.update(env_vars_from_file(env_file)) env.update(parse_environment(service_dict.get('environment'))) return dict(resolve_env_var(k, v) for k, v in six.iteritems(env)) def validate_extended_service_dict(service_dict, filename, service): error_prefix = "Cannot extend service '%s' in %s:" % (service, filename) if 'links' in service_dict: raise ConfigurationError( "%s services with 'links' cannot be extended" % error_prefix) if 'volumes_from' in service_dict: raise ConfigurationError( "%s services with 'volumes_from' cannot be extended" % error_prefix) if 'net' in service_dict: if get_service_name_from_net(service_dict['net']) is not None: raise ConfigurationError( "%s services with 'net: container' cannot be extended" % error_prefix) def validate_ulimits(ulimit_config): for limit_name, soft_hard_values in six.iteritems(ulimit_config): if isinstance(soft_hard_values, dict): if not soft_hard_values['soft'] <= soft_hard_values['hard']: raise ConfigurationError( "ulimit_config \"{}\" cannot contain a 'soft' value higher " "than 'hard' value".format(ulimit_config)) # TODO: rename to normalize_service def process_service(service_config): working_dir = service_config.working_dir service_dict = dict(service_config.config) if 'env_file' in service_dict: service_dict['env_file'] = [ expand_path(working_dir, path) for path in to_list(service_dict['env_file']) ] if 'volumes' in service_dict and service_dict.get('volume_driver') is None: service_dict['volumes'] = resolve_volume_paths(working_dir, service_dict) if 'build' in service_dict: service_dict['build'] = resolve_build_path(working_dir, service_dict['build']) if 'labels' in service_dict: service_dict['labels'] = parse_labels(service_dict['labels']) if 'extra_hosts' in service_dict: service_dict['extra_hosts'] = parse_extra_hosts(service_dict['extra_hosts']) for field in ['dns', 'dns_search']: if field in service_dict: service_dict[field] = to_list(service_dict[field]) # TODO: move to a validate_service() if 'ulimits' in service_dict: validate_ulimits(service_dict['ulimits']) return service_dict def finalize_service(service_config): service_dict = dict(service_config.config) if 'environment' in service_dict or 'env_file' in service_dict: service_dict['environment'] = resolve_environment(service_dict) service_dict.pop('env_file', None) if 'volumes_from' in service_dict: service_dict['volumes_from'] = [ VolumeFromSpec.parse(vf) for vf in service_dict['volumes_from']] if 'volumes' in service_dict: service_dict['volumes'] = [ VolumeSpec.parse(v) for v in service_dict['volumes']] if 'restart' in service_dict: service_dict['restart'] = parse_restart_spec(service_dict['restart']) return normalize_v1_service_format(service_dict) def normalize_v1_service_format(service_dict): if 'log_driver' in service_dict or 'log_opt' in service_dict: if 'logging' not in service_dict: service_dict['logging'] = {} if 'log_driver' in service_dict: service_dict['logging']['driver'] = service_dict['log_driver'] del service_dict['log_driver'] if 'log_opt' in service_dict: service_dict['logging']['options'] = service_dict['log_opt'] del service_dict['log_opt'] return service_dict def merge_service_dicts_from_files(base, override, version): """When merging services from multiple files we need to merge the `extends` field. This is not handled by `merge_service_dicts()` which is used to perform the `extends`. """ new_service = merge_service_dicts(base, override, version) if 'extends' in override: new_service['extends'] = override['extends'] elif 'extends' in base: new_service['extends'] = base['extends'] return new_service def merge_service_dicts(base, override, version): d = {} def merge_field(field, merge_func, default=None): if field in base or field in override: d[field] = merge_func( base.get(field, default), override.get(field, default)) def merge_mapping(mapping, parse_func): if mapping in base or mapping in override: merged = parse_func(base.get(mapping, None)) merged.update(parse_func(override.get(mapping, None))) d[mapping] = merged merge_mapping('environment', parse_environment) merge_mapping('labels', parse_labels) merge_mapping('ulimits', parse_ulimits) for field in ['volumes', 'devices']: merge_field(field, merge_path_mappings) for field in ['ports', 'expose', 'external_links']: merge_field(field, operator.add, default=[]) for field in ['dns', 'dns_search', 'env_file']: merge_field(field, merge_list_or_string) for field in set(ALLOWED_KEYS) - set(d): if field in base or field in override: d[field] = override.get(field, base.get(field)) if version == 1: legacy_v1_merge_image_or_build(d, base, override) return d def legacy_v1_merge_image_or_build(output, base, override): output.pop('image', None) output.pop('build', None) if 'image' in override: output['image'] = override['image'] elif 'build' in override: output['build'] = override['build'] elif 'image' in base: output['image'] = base['image'] elif 'build' in base: output['build'] = base['build'] def merge_environment(base, override): env = parse_environment(base) env.update(parse_environment(override)) return env def parse_environment(environment): if not environment: return {} if isinstance(environment, list): return dict(split_env(e) for e in environment) if isinstance(environment, dict): return dict(environment) raise ConfigurationError( "environment \"%s\" must be a list or mapping," % environment ) def split_env(env): if isinstance(env, six.binary_type): env = env.decode('utf-8', 'replace') if '=' in env: return env.split('=', 1) else: return env, None def resolve_env_var(key, val): if val is not None: return key, val elif key in os.environ: return key, os.environ[key] else: return key, '' def env_vars_from_file(filename): """ Read in a line delimited file of environment variables. """ if not os.path.exists(filename): raise ConfigurationError("Couldn't find env file: %s" % filename) env = {} for line in codecs.open(filename, 'r', 'utf-8'): line = line.strip() if line and not line.startswith('#'): k, v = split_env(line) env[k] = v return env def resolve_volume_paths(working_dir, service_dict): return [ resolve_volume_path(working_dir, volume) for volume in service_dict['volumes'] ] def resolve_volume_path(working_dir, volume): container_path, host_path = split_path_mapping(volume) if host_path is not None: if host_path.startswith('.'): host_path = expand_path(working_dir, host_path) host_path = os.path.expanduser(host_path) return u"{}:{}".format(host_path, container_path) else: return container_path def resolve_build_path(working_dir, build_path): if is_url(build_path): return build_path return expand_path(working_dir, build_path) def is_url(build_path): return build_path.startswith(DOCKER_VALID_URL_PREFIXES) def validate_paths(service_dict): if 'build' in service_dict: build_path = service_dict['build'] if ( not is_url(build_path) and (not os.path.exists(build_path) or not os.access(build_path, os.R_OK)) ): raise ConfigurationError( "build path %s either does not exist, is not accessible, " "or is not a valid URL." % build_path) def merge_path_mappings(base, override): d = dict_from_path_mappings(base) d.update(dict_from_path_mappings(override)) return path_mappings_from_dict(d) def dict_from_path_mappings(path_mappings): if path_mappings: return dict(split_path_mapping(v) for v in path_mappings) else: return {} def path_mappings_from_dict(d): return [join_path_mapping(v) for v in d.items()] def split_path_mapping(volume_path): """ Ascertain if the volume_path contains a host path as well as a container path. Using splitdrive so windows absolute paths won't cause issues with splitting on ':'. """ # splitdrive has limitations when it comes to relative paths, so when it's # relative, handle special case to set the drive to '' if volume_path.startswith('.') or volume_path.startswith('~'): drive, volume_config = '', volume_path else: drive, volume_config = os.path.splitdrive(volume_path) if ':' in volume_config: (host, container) = volume_config.split(':', 1) return (container, drive + host) else: return (volume_path, None) def join_path_mapping(pair): (container, host) = pair if host is None: return container else: return ":".join((host, container)) def parse_labels(labels): if not labels: return {} if isinstance(labels, list): return dict(split_label(e) for e in labels) if isinstance(labels, dict): return dict(labels) def split_label(label): if '=' in label: return label.split('=', 1) else: return label, '' def parse_ulimits(ulimits): if not ulimits: return {} if isinstance(ulimits, dict): return dict(ulimits) def expand_path(working_dir, path): return os.path.abspath(os.path.join(working_dir, os.path.expanduser(path))) def merge_list_or_string(base, override): return to_list(base) + to_list(override) def to_list(value): if value is None: return [] elif isinstance(value, six.string_types): return [value] else: return value def load_yaml(filename): try: with open(filename, 'r') as fh: return yaml.safe_load(fh) except (IOError, yaml.YAMLError) as e: error_name = getattr(e, '__module__', '') + '.' + e.__class__.__name__ raise ConfigurationError(u"{}: {}".format(error_name, e))