| # |
| # Copyright (C) 2018 Codethink Limited |
| # Copyright (C) 2019 Bloomberg LLP |
| # |
| # This program is free software; you can redistribute it and/or |
| # modify it under the terms of the GNU Lesser General Public |
| # License as published by the Free Software Foundation; either |
| # version 2 of the License, or (at your option) any later version. |
| # |
| # This library is distributed in the hope that it will be useful, |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| # Lesser General Public License for more details. |
| # |
| # You should have received a copy of the GNU Lesser General Public |
| # License along with this library. If not, see <http://www.gnu.org/licenses/>. |
| # |
| # Authors: |
| # Tristan Van Berkom <tristan.vanberkom@codethink.co.uk> |
| # Daniel Silverstone <daniel.silverstone@codethink.co.uk> |
| # James Ennis <james.ennis@codethink.co.uk> |
| |
| import sys |
| import string |
| from contextlib import ExitStack |
| from collections import OrderedDict, namedtuple |
| from collections.abc import Mapping, Sequence |
| from copy import deepcopy |
| from itertools import count |
| |
| from ruamel import yaml |
| from ._exceptions import LoadError, LoadErrorReason |
| |
| |
| # Without this, pylint complains about all the `type(foo) is blah` checks |
| # because it feels isinstance() is more idiomatic. Sadly, it is much slower to |
| # do `isinstance(foo, blah)` for reasons I am unable to fathom. As such, we |
| # blanket disable the check for this module. |
| # |
| # pylint: disable=unidiomatic-typecheck |
| |
| |
| # Node() |
| # |
| # Container for YAML loaded data and its provenance |
| # |
| # All nodes returned (and all internal lists/strings) have this type (rather |
| # than a plain tuple, to distinguish them in things like node_sanitize) |
| # |
| # Members: |
| # value (str/list/dict): The loaded value. |
| # file_index (int): Index within _FILE_LIST (a list of loaded file paths). |
| # Negative indices indicate synthetic nodes so that |
| # they can be referenced. |
| # line (int): The line number within the file where the value appears. |
| # col (int): The column number within the file where the value appears. |
| # |
| # For efficiency, each field should be accessed by its integer index: |
| # value = Node[0] |
| # file_index = Node[1] |
| # line = Node[2] |
| # column = Node[3] |
| # |
| class Node(namedtuple('Node', ['value', 'file_index', 'line', 'column'])): |
| def __contains__(self, what): |
| # Delegate to the inner value, though this will likely not work |
| # very well if the node is a list or string, it's unlikely that |
| # code which has access to such nodes would do this. |
| return what in self[0] |
| |
| |
| # File name handling |
| _FILE_LIST = [] |
| |
| |
| # Purely synthetic node will have None for the file number, have line number |
| # zero, and a negative column number which comes from inverting the next value |
| # out of this counter. Synthetic nodes created with a reference node will |
| # have a file number from the reference node, some unknown line number, and |
| # a negative column number from this counter. |
| _SYNTHETIC_COUNTER = count(start=-1, step=-1) |
| |
| |
| # Returned from node_get_provenance |
| class ProvenanceInformation: |
| |
| __slots__ = ( |
| "filename", |
| "shortname", |
| "displayname", |
| "line", |
| "col", |
| "toplevel", |
| "node", |
| "project", |
| "is_synthetic", |
| ) |
| |
| def __init__(self, nodeish): |
| self.node = nodeish |
| if (nodeish is None) or (nodeish[1] is None): |
| self.filename = "" |
| self.shortname = "" |
| self.displayname = "" |
| self.line = 1 |
| self.col = 0 |
| self.toplevel = None |
| self.project = None |
| else: |
| fileinfo = _FILE_LIST[nodeish[1]] |
| self.filename = fileinfo[0] |
| self.shortname = fileinfo[1] |
| self.displayname = fileinfo[2] |
| # We add 1 here to convert from computerish to humanish |
| self.line = nodeish[2] + 1 |
| self.col = nodeish[3] |
| self.toplevel = fileinfo[3] |
| self.project = fileinfo[4] |
| self.is_synthetic = (self.filename == '') or (self.col < 0) |
| |
| # Convert a Provenance to a string for error reporting |
| def __str__(self): |
| if self.is_synthetic: |
| return "{} [synthetic node]".format(self.displayname) |
| else: |
| return "{} [line {:d} column {:d}]".format(self.displayname, self.line, self.col) |
| |
| |
| # These exceptions are intended to be caught entirely within |
| # the BuildStream framework, hence they do not reside in the |
| # public exceptions.py |
| class CompositeError(Exception): |
| def __init__(self, path, message): |
| super(CompositeError, self).__init__(message) |
| self.path = path |
| self.message = message |
| |
| |
| class YAMLLoadError(Exception): |
| pass |
| |
| |
| # Representer for YAML events comprising input to the BuildStream format. |
| # |
| # All streams MUST represent a single document which must be a Mapping. |
| # Anything else is considered an error. |
| # |
| # Mappings must only have string keys, values are always represented as |
| # strings if they are scalar, or else as simple dictionaries and lists. |
| # |
| class Representer: |
| __slots__ = ( |
| "_file_index", |
| "state", |
| "output", |
| "keys", |
| ) |
| |
| # Initialise a new representer |
| # |
| # The file index is used to store into the Node instances so that the |
| # provenance of the YAML can be tracked. |
| # |
| # Args: |
| # file_index (int): The index of this YAML file |
| def __init__(self, file_index): |
| self._file_index = file_index |
| self.state = "init" |
| self.output = [] |
| self.keys = [] |
| |
| # Handle a YAML parse event |
| # |
| # Args: |
| # event (YAML Event): The event to be handled |
| # |
| # Raises: |
| # YAMLLoadError: Something went wrong. |
| def handle_event(self, event): |
| if getattr(event, "anchor", None) is not None: |
| raise YAMLLoadError("Anchors are disallowed in BuildStream at line {} column {}" |
| .format(event.start_mark.line, event.start_mark.column)) |
| |
| if event.__class__.__name__ == "ScalarEvent": |
| if event.tag is not None: |
| if not event.tag.startswith("tag:yaml.org,2002:"): |
| raise YAMLLoadError( |
| "Non-core tag expressed in input. " + |
| "This is disallowed in BuildStream. At line {} column {}" |
| .format(event.start_mark.line, event.start_mark.column)) |
| |
| handler = "_handle_{}_{}".format(self.state, event.__class__.__name__) |
| handler = getattr(self, handler, None) |
| if handler is None: |
| raise YAMLLoadError( |
| "Invalid input detected. No handler for {} in state {} at line {} column {}" |
| .format(event, self.state, event.start_mark.line, event.start_mark.column)) |
| |
| self.state = handler(event) # pylint: disable=not-callable |
| |
| # Get the output of the YAML parse |
| # |
| # Returns: |
| # (Node or None): Return the Node instance of the top level mapping or |
| # None if there wasn't one. |
| def get_output(self): |
| try: |
| return self.output[0] |
| except IndexError: |
| return None |
| |
| def _handle_init_StreamStartEvent(self, ev): |
| return "stream" |
| |
| def _handle_stream_DocumentStartEvent(self, ev): |
| return "doc" |
| |
| def _handle_doc_MappingStartEvent(self, ev): |
| newmap = Node({}, self._file_index, ev.start_mark.line, ev.start_mark.column) |
| self.output.append(newmap) |
| return "wait_key" |
| |
| def _handle_wait_key_ScalarEvent(self, ev): |
| self.keys.append(ev.value) |
| return "wait_value" |
| |
| def _handle_wait_value_ScalarEvent(self, ev): |
| key = self.keys.pop() |
| self.output[-1][0][key] = \ |
| Node(ev.value, self._file_index, ev.start_mark.line, ev.start_mark.column) |
| return "wait_key" |
| |
| def _handle_wait_value_MappingStartEvent(self, ev): |
| new_state = self._handle_doc_MappingStartEvent(ev) |
| key = self.keys.pop() |
| self.output[-2][0][key] = self.output[-1] |
| return new_state |
| |
| def _handle_wait_key_MappingEndEvent(self, ev): |
| # We've finished a mapping, so pop it off the output stack |
| # unless it's the last one in which case we leave it |
| if len(self.output) > 1: |
| self.output.pop() |
| if type(self.output[-1][0]) is list: |
| return "wait_list_item" |
| else: |
| return "wait_key" |
| else: |
| return "doc" |
| |
| def _handle_wait_value_SequenceStartEvent(self, ev): |
| self.output.append(Node([], self._file_index, ev.start_mark.line, ev.start_mark.column)) |
| self.output[-2][0][self.keys[-1]] = self.output[-1] |
| return "wait_list_item" |
| |
| def _handle_wait_list_item_SequenceStartEvent(self, ev): |
| self.keys.append(len(self.output[-1][0])) |
| self.output.append(Node([], self._file_index, ev.start_mark.line, ev.start_mark.column)) |
| self.output[-2][0].append(self.output[-1]) |
| return "wait_list_item" |
| |
| def _handle_wait_list_item_SequenceEndEvent(self, ev): |
| # When ending a sequence, we need to pop a key because we retain the |
| # key until the end so that if we need to mutate the underlying entry |
| # we can. |
| key = self.keys.pop() |
| self.output.pop() |
| if type(key) is int: |
| return "wait_list_item" |
| else: |
| return "wait_key" |
| |
| def _handle_wait_list_item_ScalarEvent(self, ev): |
| self.output[-1][0].append( |
| Node(ev.value, self._file_index, ev.start_mark.line, ev.start_mark.column)) |
| return "wait_list_item" |
| |
| def _handle_wait_list_item_MappingStartEvent(self, ev): |
| new_state = self._handle_doc_MappingStartEvent(ev) |
| self.output[-2][0].append(self.output[-1]) |
| return new_state |
| |
| def _handle_doc_DocumentEndEvent(self, ev): |
| if len(self.output) != 1: |
| raise YAMLLoadError("Zero, or more than one document found in YAML stream") |
| return "stream" |
| |
| def _handle_stream_StreamEndEvent(self, ev): |
| return "init" |
| |
| |
| # Loads a dictionary from some YAML |
| # |
| # Args: |
| # filename (str): The YAML file to load |
| # shortname (str): The filename in shorthand for error reporting (or None) |
| # copy_tree (bool): Whether to make a copy, preserving the original toplevels |
| # for later serialization |
| # project (Project): The (optional) project to associate the parsed YAML with |
| # |
| # Returns (dict): A loaded copy of the YAML file with provenance information |
| # |
| # Raises: LoadError |
| # |
| def load(filename, shortname=None, copy_tree=False, *, project=None): |
| if not shortname: |
| shortname = filename |
| |
| if (project is not None) and (project.junction is not None): |
| displayname = "{}:{}".format(project.junction.name, shortname) |
| else: |
| displayname = shortname |
| |
| file_number = len(_FILE_LIST) |
| _FILE_LIST.append((filename, shortname, displayname, None, project)) |
| |
| try: |
| with open(filename) as f: |
| contents = f.read() |
| |
| data = load_data(contents, |
| file_index=file_number, |
| file_name=filename, |
| copy_tree=copy_tree) |
| |
| return data |
| except FileNotFoundError as e: |
| raise LoadError(LoadErrorReason.MISSING_FILE, |
| "Could not find file at {}".format(filename)) from e |
| except IsADirectoryError as e: |
| raise LoadError(LoadErrorReason.LOADING_DIRECTORY, |
| "{} is a directory. bst command expects a .bst file." |
| .format(filename)) from e |
| except LoadError as e: |
| raise LoadError(e.reason, "{}: {}".format(displayname, e)) from e |
| |
| |
| # Like load(), but doesnt require the data to be in a file |
| # |
| def load_data(data, file_index=None, file_name=None, copy_tree=False): |
| |
| try: |
| rep = Representer(file_index) |
| for event in yaml.parse(data, Loader=yaml.CBaseLoader): |
| rep.handle_event(event) |
| contents = rep.get_output() |
| except YAMLLoadError as e: |
| raise LoadError(LoadErrorReason.INVALID_YAML, |
| "Malformed YAML:\n\n{}\n\n".format(e)) from e |
| except Exception as e: |
| raise LoadError(LoadErrorReason.INVALID_YAML, |
| "Severely malformed YAML:\n\n{}\n\n".format(e)) from e |
| |
| if not isinstance(contents, tuple) or not isinstance(contents[0], dict): |
| # Special case allowance for None, when the loaded file has only comments in it. |
| if contents is None: |
| contents = Node({}, file_index, 0, 0) |
| else: |
| raise LoadError(LoadErrorReason.INVALID_YAML, |
| "YAML file has content of type '{}' instead of expected type 'dict': {}" |
| .format(type(contents[0]).__name__, file_name)) |
| |
| # Store this away because we'll use it later for "top level" provenance |
| if file_index is not None: |
| _FILE_LIST[file_index] = ( |
| _FILE_LIST[file_index][0], # Filename |
| _FILE_LIST[file_index][1], # Shortname |
| _FILE_LIST[file_index][2], # Displayname |
| contents, |
| _FILE_LIST[file_index][4], # Project |
| ) |
| |
| if copy_tree: |
| contents = node_copy(contents) |
| return contents |
| |
| |
| # dump() |
| # |
| # Write a YAML node structure out to disk. |
| # |
| # This will always call `node_sanitize` on its input, so if you wanted |
| # to output something close to what you read in, consider using the |
| # `roundtrip_load` and `roundtrip_dump` function pair instead. |
| # |
| # Args: |
| # contents (any): Content to write out |
| # filename (str): The (optional) file name to write out to |
| def dump(contents, filename=None): |
| roundtrip_dump(node_sanitize(contents), file=filename) |
| |
| |
| # node_get_provenance() |
| # |
| # Gets the provenance for a node |
| # |
| # Args: |
| # node (dict): a dictionary |
| # key (str): key in the dictionary |
| # indices (list of indexes): Index path, in the case of list values |
| # |
| # Returns: The Provenance of the dict, member or list element |
| # |
| def node_get_provenance(node, key=None, indices=None): |
| assert is_node(node) |
| |
| if key is None: |
| # Retrieving the provenance for this node directly |
| return ProvenanceInformation(node) |
| |
| if key and not indices: |
| return ProvenanceInformation(node[0].get(key)) |
| |
| nodeish = node[0].get(key) |
| for idx in indices: |
| nodeish = nodeish[0][idx] |
| |
| return ProvenanceInformation(nodeish) |
| |
| |
| # A sentinel to be used as a default argument for functions that need |
| # to distinguish between a kwarg set to None and an unset kwarg. |
| _sentinel = object() |
| |
| |
| # node_get() |
| # |
| # Fetches a value from a dictionary node and checks it for |
| # an expected value. Use default_value when parsing a value |
| # which is only optionally supplied. |
| # |
| # Args: |
| # node (dict): The dictionary node |
| # expected_type (type): The expected type for the value being searched |
| # key (str): The key to get a value for in node |
| # indices (list of ints): Optionally decend into lists of lists |
| # default_value: Optionally return this value if the key is not found |
| # allow_none: (bool): Allow None to be a valid value |
| # |
| # Returns: |
| # The value if found in node, otherwise default_value is returned |
| # |
| # Raises: |
| # LoadError, when the value found is not of the expected type |
| # |
| # Note: |
| # Returned strings are stripped of leading and trailing whitespace |
| # |
| def node_get(node, expected_type, key, indices=None, *, default_value=_sentinel, allow_none=False): |
| assert type(node) is Node |
| |
| if indices is None: |
| if default_value is _sentinel: |
| value = node[0].get(key, Node(default_value, None, 0, 0)) |
| else: |
| value = node[0].get(key, Node(default_value, None, 0, next(_SYNTHETIC_COUNTER))) |
| |
| if value[0] is _sentinel: |
| provenance = node_get_provenance(node) |
| raise LoadError(LoadErrorReason.INVALID_DATA, |
| "{}: Dictionary did not contain expected key '{}'".format(provenance, key)) |
| else: |
| # Implied type check of the element itself |
| # No need to synthesise useful node content as we destructure it immediately |
| value = Node(node_get(node, list, key), None, 0, 0) |
| for index in indices: |
| value = value[0][index] |
| if type(value) is not Node: |
| value = (value,) |
| |
| # Optionally allow None as a valid value for any type |
| if value[0] is None and (allow_none or default_value is None): |
| return None |
| |
| if (expected_type is not None) and (not isinstance(value[0], expected_type)): |
| # Attempt basic conversions if possible, typically we want to |
| # be able to specify numeric values and convert them to strings, |
| # but we dont want to try converting dicts/lists |
| try: |
| if (expected_type == bool and isinstance(value[0], str)): |
| # Dont coerce booleans to string, this makes "False" strings evaluate to True |
| # We don't structure into full nodes since there's no need. |
| if value[0] in ('True', 'true'): |
| value = (True, None, 0, 0) |
| elif value[0] in ('False', 'false'): |
| value = (False, None, 0, 0) |
| else: |
| raise ValueError() |
| elif not (expected_type == list or |
| expected_type == dict or |
| isinstance(value[0], (list, dict))): |
| value = (expected_type(value[0]), None, 0, 0) |
| else: |
| raise ValueError() |
| except (ValueError, TypeError): |
| provenance = node_get_provenance(node, key=key, indices=indices) |
| if indices: |
| path = [key] |
| path.extend("[{:d}]".format(i) for i in indices) |
| path = "".join(path) |
| else: |
| path = key |
| raise LoadError(LoadErrorReason.INVALID_DATA, |
| "{}: Value of '{}' is not of the expected type '{}'" |
| .format(provenance, path, expected_type.__name__)) |
| |
| # Now collapse lists, and scalars, to their value, leaving nodes as-is |
| if type(value[0]) is not dict: |
| value = value[0] |
| |
| # Trim it at the bud, let all loaded strings from yaml be stripped of whitespace |
| if type(value) is str: |
| value = value.strip() |
| |
| elif type(value) is list: |
| # Now we create a fresh list which unwraps the str and list types |
| # semi-recursively. |
| value = __trim_list_provenance(value) |
| |
| return value |
| |
| |
| def __trim_list_provenance(value): |
| ret = [] |
| for entry in value: |
| if type(entry) is not Node: |
| entry = (entry, None, 0, 0) |
| if type(entry[0]) is list: |
| ret.append(__trim_list_provenance(entry[0])) |
| elif type(entry[0]) is dict: |
| ret.append(entry) |
| else: |
| ret.append(entry[0]) |
| return ret |
| |
| |
| # node_set() |
| # |
| # Set an item within the node. If using `indices` be aware that the entry must |
| # already exist, or else a KeyError will be raised. Use `node_extend_list` to |
| # create entries before using `node_set` |
| # |
| # Args: |
| # node (tuple): The node |
| # key (str): The key name |
| # value: The value |
| # indices: Any indices to index into the list referenced by key, like in |
| # `node_get` (must be a list of integers) |
| # |
| def node_set(node, key, value, indices=None): |
| if indices: |
| node = node[0][key] |
| key = indices.pop() |
| for idx in indices: |
| node = node[0][idx] |
| if type(value) is Node: |
| node[0][key] = value |
| else: |
| try: |
| # Need to do this just in case we're modifying a list |
| old_value = node[0][key] |
| except KeyError: |
| old_value = None |
| if old_value is None: |
| node[0][key] = Node(value, node[1], node[2], next(_SYNTHETIC_COUNTER)) |
| else: |
| node[0][key] = Node(value, old_value[1], old_value[2], old_value[3]) |
| |
| |
| # node_extend_list() |
| # |
| # Extend a list inside a node to a given length, using the passed |
| # default value to fill it out. |
| # |
| # Valid default values are: |
| # Any string |
| # An empty dict |
| # An empty list |
| # |
| # Args: |
| # node (node): The node |
| # key (str): The list name in the node |
| # length (int): The length to extend the list to |
| # default (any): The default value to extend with. |
| def node_extend_list(node, key, length, default): |
| assert type(default) is str or default in ([], {}) |
| |
| list_node = node[0].get(key) |
| if list_node is None: |
| list_node = node[0][key] = Node([], node[1], node[2], next(_SYNTHETIC_COUNTER)) |
| |
| assert type(list_node[0]) is list |
| |
| the_list = list_node[0] |
| def_type = type(default) |
| |
| file_index = node[1] |
| if the_list: |
| line_num = the_list[-1][2] |
| else: |
| line_num = list_node[2] |
| |
| while length > len(the_list): |
| if def_type is str: |
| value = default |
| elif def_type is list: |
| value = [] |
| else: |
| value = {} |
| |
| line_num += 1 |
| |
| the_list.append(Node(value, file_index, line_num, next(_SYNTHETIC_COUNTER))) |
| |
| |
| # node_items() |
| # |
| # A convenience generator for iterating over loaded key/value |
| # tuples in a dictionary loaded from project YAML. |
| # |
| # Args: |
| # node (dict): The dictionary node |
| # |
| # Yields: |
| # (str): The key name |
| # (anything): The value for the key |
| # |
| def node_items(node): |
| if type(node) is not Node: |
| node = Node(node, None, 0, 0) |
| for key, value in node[0].items(): |
| if type(value) is not Node: |
| value = Node(value, None, 0, 0) |
| if type(value[0]) is dict: |
| yield (key, value) |
| elif type(value[0]) is list: |
| yield (key, __trim_list_provenance(value[0])) |
| else: |
| yield (key, value[0]) |
| |
| |
| # node_keys() |
| # |
| # A convenience generator for iterating over loaded keys |
| # in a dictionary loaded from project YAML. |
| # |
| # Args: |
| # node (dict): The dictionary node |
| # |
| # Yields: |
| # (str): The key name |
| # |
| def node_keys(node): |
| if type(node) is not Node: |
| node = Node(node, None, 0, 0) |
| yield from node[0].keys() |
| |
| |
| # node_del() |
| # |
| # A convenience generator for iterating over loaded key/value |
| # tuples in a dictionary loaded from project YAML. |
| # |
| # Args: |
| # node (dict): The dictionary node |
| # key (str): The key we want to remove |
| # safe (bool): Whether to raise a KeyError if unable |
| # |
| def node_del(node, key, safe=False): |
| try: |
| del node[0][key] |
| except KeyError: |
| if not safe: |
| raise |
| |
| |
| # is_node() |
| # |
| # A test method which returns whether or not the passed in value |
| # is a valid YAML node. It is not valid to call this on a Node |
| # object which is not a Mapping. |
| # |
| # Args: |
| # maybenode (any): The object to test for nodeness |
| # |
| # Returns: |
| # (bool): Whether or not maybenode was a Node |
| # |
| def is_node(maybenode): |
| # It's a programming error to give this a Node which isn't a mapping |
| # so assert that. |
| assert (type(maybenode) is not Node) or (type(maybenode[0]) is dict) |
| # Now return the type check |
| return type(maybenode) is Node |
| |
| |
| # new_synthetic_file() |
| # |
| # Create a new synthetic mapping node, with an associated file entry |
| # (in _FILE_LIST) such that later tracking can correctly determine which |
| # file needs writing to in order to persist the changes. |
| # |
| # Args: |
| # filename (str): The name of the synthetic file to create |
| # project (Project): The optional project to associate this synthetic file with |
| # |
| # Returns: |
| # (Node): An empty YAML mapping node, whose provenance is to this new |
| # synthetic file |
| # |
| def new_synthetic_file(filename, project=None): |
| file_index = len(_FILE_LIST) |
| node = Node({}, file_index, 0, 0) |
| _FILE_LIST.append((filename, |
| filename, |
| "<synthetic {}>".format(filename), |
| node, |
| project)) |
| return node |
| |
| |
| # new_empty_node() |
| # |
| # Args: |
| # ref_node (Node): Optional node whose provenance should be referenced |
| # |
| # Returns |
| # (Node): A new empty YAML mapping node |
| # |
| def new_empty_node(ref_node=None): |
| if ref_node is not None: |
| return Node({}, ref_node[1], ref_node[2], next(_SYNTHETIC_COUNTER)) |
| else: |
| return Node({}, None, 0, 0) |
| |
| |
| # new_node_from_dict() |
| # |
| # Args: |
| # indict (dict): The input dictionary |
| # |
| # Returns: |
| # (Node): A new synthetic YAML tree which represents this dictionary |
| # |
| def new_node_from_dict(indict): |
| ret = {} |
| for k, v in indict.items(): |
| vtype = type(v) |
| if vtype is dict: |
| ret[k] = new_node_from_dict(v) |
| elif vtype is list: |
| ret[k] = __new_node_from_list(v) |
| else: |
| ret[k] = Node(str(v), None, 0, next(_SYNTHETIC_COUNTER)) |
| return Node(ret, None, 0, next(_SYNTHETIC_COUNTER)) |
| |
| |
| # Internal function to help new_node_from_dict() to handle lists |
| def __new_node_from_list(inlist): |
| ret = [] |
| for v in inlist: |
| vtype = type(v) |
| if vtype is dict: |
| ret.append(new_node_from_dict(v)) |
| elif vtype is list: |
| ret.append(__new_node_from_list(v)) |
| else: |
| ret.append(Node(str(v), None, 0, next(_SYNTHETIC_COUNTER))) |
| return Node(ret, None, 0, next(_SYNTHETIC_COUNTER)) |
| |
| |
| # _is_composite_list |
| # |
| # Checks if the given node is a Mapping with array composition |
| # directives. |
| # |
| # Args: |
| # node (value): Any node |
| # |
| # Returns: |
| # (bool): True if node was a Mapping containing only |
| # list composition directives |
| # |
| # Raises: |
| # (LoadError): If node was a mapping and contained a mix of |
| # list composition directives and other keys |
| # |
| def _is_composite_list(node): |
| |
| if type(node[0]) is dict: |
| has_directives = False |
| has_keys = False |
| |
| for key, _ in node_items(node): |
| if key in ['(>)', '(<)', '(=)']: # pylint: disable=simplifiable-if-statement |
| has_directives = True |
| else: |
| has_keys = True |
| |
| if has_keys and has_directives: |
| provenance = node_get_provenance(node) |
| raise LoadError(LoadErrorReason.INVALID_DATA, |
| "{}: Dictionary contains array composition directives and arbitrary keys" |
| .format(provenance)) |
| return has_directives |
| |
| return False |
| |
| |
| # _compose_composite_list() |
| # |
| # Composes a composite list (i.e. a dict with list composition directives) |
| # on top of a target list which is a composite list itself. |
| # |
| # Args: |
| # target (Node): A composite list |
| # source (Node): A composite list |
| # |
| def _compose_composite_list(target, source): |
| clobber = source[0].get("(=)") |
| prefix = source[0].get("(<)") |
| suffix = source[0].get("(>)") |
| if clobber is not None: |
| # We want to clobber the target list |
| # which basically means replacing the target list |
| # with ourselves |
| target[0]["(=)"] = clobber |
| if prefix is not None: |
| target[0]["(<)"] = prefix |
| elif "(<)" in target[0]: |
| target[0]["(<)"][0].clear() |
| if suffix is not None: |
| target[0]["(>)"] = suffix |
| elif "(>)" in target[0]: |
| target[0]["(>)"][0].clear() |
| else: |
| # Not clobbering, so prefix the prefix and suffix the suffix |
| if prefix is not None: |
| if "(<)" in target[0]: |
| for v in reversed(prefix[0]): |
| target[0]["(<)"][0].insert(0, v) |
| else: |
| target[0]["(<)"] = prefix |
| if suffix is not None: |
| if "(>)" in target[0]: |
| target[0]["(>)"][0].extend(suffix[0]) |
| else: |
| target[0]["(>)"] = suffix |
| |
| |
| # _compose_list() |
| # |
| # Compose a composite list (a dict with composition directives) on top of a |
| # simple list. |
| # |
| # Args: |
| # target (Node): The target list to be composed into |
| # source (Node): The composition list to be composed from |
| # |
| def _compose_list(target, source): |
| clobber = source[0].get("(=)") |
| prefix = source[0].get("(<)") |
| suffix = source[0].get("(>)") |
| if clobber is not None: |
| target[0].clear() |
| target[0].extend(clobber[0]) |
| if prefix is not None: |
| for v in reversed(prefix[0]): |
| target[0].insert(0, v) |
| if suffix is not None: |
| target[0].extend(suffix[0]) |
| |
| |
| # composite_dict() |
| # |
| # Compose one mapping node onto another |
| # |
| # Args: |
| # target (Node): The target to compose into |
| # source (Node): The source to compose from |
| # path (list): The path to the current composition node |
| # |
| # Raises: CompositeError |
| # |
| def composite_dict(target, source, path=None): |
| if path is None: |
| path = [] |
| for k, v in source[0].items(): |
| path.append(k) |
| if type(v[0]) is list: |
| # List clobbers anything list-like |
| target_value = target[0].get(k) |
| if not (target_value is None or |
| type(target_value[0]) is list or |
| _is_composite_list(target_value)): |
| raise CompositeError(path, |
| "{}: List cannot overwrite {} at: {}" |
| .format(node_get_provenance(source, k), |
| k, |
| node_get_provenance(target, k))) |
| # Looks good, clobber it |
| target[0][k] = v |
| elif _is_composite_list(v): |
| if k not in target[0]: |
| # Composite list clobbers empty space |
| target[0][k] = v |
| elif type(target[0][k][0]) is list: |
| # Composite list composes into a list |
| _compose_list(target[0][k], v) |
| elif _is_composite_list(target[0][k]): |
| # Composite list merges into composite list |
| _compose_composite_list(target[0][k], v) |
| else: |
| # Else composing on top of normal dict or a scalar, so raise... |
| raise CompositeError(path, |
| "{}: Cannot compose lists onto {}".format( |
| node_get_provenance(v), |
| node_get_provenance(target[0][k]))) |
| elif type(v[0]) is dict: |
| # We're composing a dict into target now |
| if k not in target[0]: |
| # Target lacks a dict at that point, make a fresh one with |
| # the same provenance as the incoming dict |
| target[0][k] = Node({}, v[1], v[2], v[3]) |
| if type(target[0]) is not dict: |
| raise CompositeError(path, |
| "{}: Cannot compose dictionary onto {}".format( |
| node_get_provenance(v), |
| node_get_provenance(target[0][k]))) |
| composite_dict(target[0][k], v, path) |
| else: |
| target_value = target[0].get(k) |
| if target_value is not None and type(target_value[0]) is not str: |
| raise CompositeError(path, |
| "{}: Cannot compose scalar on non-scalar at {}".format( |
| node_get_provenance(v), |
| node_get_provenance(target[0][k]))) |
| target[0][k] = v |
| path.pop() |
| |
| |
| # Like composite_dict(), but raises an all purpose LoadError for convenience |
| # |
| def composite(target, source): |
| assert type(source[0]) is dict |
| assert type(target[0]) is dict |
| |
| try: |
| composite_dict(target, source) |
| except CompositeError as e: |
| source_provenance = node_get_provenance(source) |
| error_prefix = "" |
| if source_provenance: |
| error_prefix = "{}: ".format(source_provenance) |
| raise LoadError(LoadErrorReason.ILLEGAL_COMPOSITE, |
| "{}Failure composing {}: {}" |
| .format(error_prefix, |
| e.path, |
| e.message)) from e |
| |
| |
| # Like composite(target, source), but where target overrides source instead. |
| # |
| def composite_and_move(target, source): |
| composite(source, target) |
| |
| to_delete = [key for key in target[0].keys() if key not in source[0]] |
| for key, value in source[0].items(): |
| target[0][key] = value |
| for key in to_delete: |
| del target[0][key] |
| |
| |
| # Types we can short-circuit in node_sanitize for speed. |
| __SANITIZE_SHORT_CIRCUIT_TYPES = (int, float, str, bool) |
| |
| |
| # node_sanitize() |
| # |
| # Returns an alphabetically ordered recursive copy |
| # of the source node with internal provenance information stripped. |
| # |
| # Only dicts are ordered, list elements are left in order. |
| # |
| def node_sanitize(node, *, dict_type=OrderedDict): |
| node_type = type(node) |
| |
| # If we have an unwrappable node, unwrap it |
| if node_type is Node: |
| node = node[0] |
| node_type = type(node) |
| |
| # Short-circuit None which occurs ca. twice per element |
| if node is None: |
| return node |
| |
| # Next short-circuit integers, floats, strings, booleans, and tuples |
| if node_type in __SANITIZE_SHORT_CIRCUIT_TYPES: |
| return node |
| |
| # Now short-circuit lists. |
| elif node_type is list: |
| return [node_sanitize(elt, dict_type=dict_type) for elt in node] |
| |
| # Finally dict, and other Mappings need special handling |
| elif node_type is dict: |
| result = dict_type() |
| |
| key_list = [key for key, _ in node.items()] |
| for key in sorted(key_list): |
| result[key] = node_sanitize(node[key], dict_type=dict_type) |
| |
| return result |
| |
| # Sometimes we're handed tuples and we can't be sure what they contain |
| # so we have to sanitize into them |
| elif node_type is tuple: |
| return tuple((node_sanitize(v, dict_type=dict_type) for v in node)) |
| |
| # Everything else just gets returned as-is. |
| return node |
| |
| |
| # node_validate() |
| # |
| # Validate the node so as to ensure the user has not specified |
| # any keys which are unrecognized by buildstream (usually this |
| # means a typo which would otherwise not trigger an error). |
| # |
| # Args: |
| # node (dict): A dictionary loaded from YAML |
| # valid_keys (list): A list of valid keys for the specified node |
| # |
| # Raises: |
| # LoadError: In the case that the specified node contained |
| # one or more invalid keys |
| # |
| def node_validate(node, valid_keys): |
| |
| # Probably the fastest way to do this: https://stackoverflow.com/a/23062482 |
| valid_keys = set(valid_keys) |
| invalid = next((key for key in node[0] if key not in valid_keys), None) |
| |
| if invalid: |
| provenance = node_get_provenance(node, key=invalid) |
| raise LoadError(LoadErrorReason.INVALID_DATA, |
| "{}: Unexpected key: {}".format(provenance, invalid)) |
| |
| |
| # Node copying |
| # |
| # Unfortunately we copy nodes a *lot* and `isinstance()` is super-slow when |
| # things from collections.abc get involved. The result is the following |
| # intricate but substantially faster group of tuples and the use of `in`. |
| # |
| # If any of the {node,list}_copy routines raise a ValueError |
| # then it's likely additional types need adding to these tuples. |
| |
| |
| # These types just have their value copied |
| __QUICK_TYPES = (str, bool) |
| |
| # These are the directives used to compose lists, we need this because it's |
| # slightly faster during the node_final_assertions checks |
| __NODE_ASSERT_COMPOSITION_DIRECTIVES = ('(>)', '(<)', '(=)') |
| |
| |
| # node_copy() |
| # |
| # Make a deep copy of the given YAML node, preserving provenance. |
| # |
| # Args: |
| # source (Node): The YAML node to copy |
| # |
| # Returns: |
| # (Node): A deep copy of source with provenance preserved. |
| # |
| def node_copy(source): |
| copy = {} |
| for key, value in source[0].items(): |
| value_type = type(value[0]) |
| if value_type is dict: |
| copy[key] = node_copy(value) |
| elif value_type is list: |
| copy[key] = _list_copy(value) |
| elif value_type in __QUICK_TYPES: |
| copy[key] = value |
| else: |
| raise ValueError("Unable to be quick about node_copy of {}".format(value_type)) |
| |
| return Node(copy, source[1], source[2], source[3]) |
| |
| |
| # Internal function to help node_copy() but for lists. |
| def _list_copy(source): |
| copy = [] |
| for item in source[0]: |
| item_type = type(item[0]) |
| if item_type is dict: |
| copy.append(node_copy(item)) |
| elif item_type is list: |
| copy.append(_list_copy(item)) |
| elif item_type in __QUICK_TYPES: |
| copy.append(item) |
| else: |
| raise ValueError("Unable to be quick about list_copy of {}".format(item_type)) |
| |
| return Node(copy, source[1], source[2], source[3]) |
| |
| |
| # node_final_assertions() |
| # |
| # This must be called on a fully loaded and composited node, |
| # after all composition has completed. |
| # |
| # Args: |
| # node (Mapping): The final composited node |
| # |
| # Raises: |
| # (LoadError): If any assertions fail |
| # |
| def node_final_assertions(node): |
| assert type(node) is Node |
| |
| for key, value in node[0].items(): |
| |
| # Assert that list composition directives dont remain, this |
| # indicates that the user intended to override a list which |
| # never existed in the underlying data |
| # |
| if key in __NODE_ASSERT_COMPOSITION_DIRECTIVES: |
| provenance = node_get_provenance(node, key) |
| raise LoadError(LoadErrorReason.TRAILING_LIST_DIRECTIVE, |
| "{}: Attempt to override non-existing list".format(provenance)) |
| |
| value_type = type(value[0]) |
| |
| if value_type is dict: |
| node_final_assertions(value) |
| elif value_type is list: |
| _list_final_assertions(value) |
| |
| |
| # Helper function for node_final_assertions(), but for lists. |
| def _list_final_assertions(values): |
| for value in values[0]: |
| value_type = type(value[0]) |
| |
| if value_type is dict: |
| node_final_assertions(value) |
| elif value_type is list: |
| _list_final_assertions(value) |
| |
| |
| # assert_symbol_name() |
| # |
| # A helper function to check if a loaded string is a valid symbol |
| # name and to raise a consistent LoadError if not. For strings which |
| # are required to be symbols. |
| # |
| # Args: |
| # provenance (Provenance): The provenance of the loaded symbol, or None |
| # symbol_name (str): The loaded symbol name |
| # purpose (str): The purpose of the string, for an error message |
| # allow_dashes (bool): Whether dashes are allowed for this symbol |
| # |
| # Raises: |
| # LoadError: If the symbol_name is invalid |
| # |
| # Note that dashes are generally preferred for variable names and |
| # usage in YAML, but things such as option names which will be |
| # evaluated with jinja2 cannot use dashes. |
| def assert_symbol_name(provenance, symbol_name, purpose, *, allow_dashes=True): |
| valid_chars = string.digits + string.ascii_letters + '_' |
| if allow_dashes: |
| valid_chars += '-' |
| |
| valid = True |
| if not symbol_name: |
| valid = False |
| elif any(x not in valid_chars for x in symbol_name): |
| valid = False |
| elif symbol_name[0] in string.digits: |
| valid = False |
| |
| if not valid: |
| detail = "Symbol names must contain only alphanumeric characters, " + \ |
| "may not start with a digit, and may contain underscores" |
| if allow_dashes: |
| detail += " or dashes" |
| |
| message = "Invalid symbol name for {}: '{}'".format(purpose, symbol_name) |
| if provenance is not None: |
| message = "{}: {}".format(provenance, message) |
| |
| raise LoadError(LoadErrorReason.INVALID_SYMBOL_NAME, |
| message, detail=detail) |
| |
| |
| # node_find_target() |
| # |
| # Searches the given node tree for the given target node. |
| # |
| # This is typically used when trying to walk a path to a given node |
| # for the purpose of then modifying a similar tree of objects elsewhere |
| # |
| # If the key is provided, then we actually hunt for the node represented by |
| # target[key] and return its container, rather than hunting for target directly |
| # |
| # Args: |
| # node (Node): The node at the root of the tree to search |
| # target (Node): The node you are looking for in that tree |
| # key (str): Optional string key within target node |
| # |
| # Returns: |
| # (list): A path from `node` to `target` or None if `target` is not in the subtree |
| def node_find_target(node, target, *, key=None): |
| assert type(node) is Node |
| assert type(target) is Node |
| if key is not None: |
| target = target[0][key] |
| |
| path = [] |
| if _walk_find_target(node, path, target): |
| if key: |
| # Remove key from end of path |
| path = path[:-1] |
| return path |
| return None |
| |
| |
| # Helper for node_find_target() which walks a value |
| def _walk_find_target(node, path, target): |
| if node[1:] == target[1:]: |
| return True |
| elif type(node[0]) is dict: |
| return _walk_dict_node(node, path, target) |
| elif type(node[0]) is list: |
| return _walk_list_node(node, path, target) |
| return False |
| |
| |
| # Helper for node_find_target() which walks a list |
| def _walk_list_node(node, path, target): |
| for i, v in enumerate(node[0]): |
| path.append(i) |
| if _walk_find_target(v, path, target): |
| return True |
| del path[-1] |
| return False |
| |
| |
| # Helper for node_find_target() which walks a mapping |
| def _walk_dict_node(node, path, target): |
| for k, v in node[0].items(): |
| path.append(k) |
| if _walk_find_target(v, path, target): |
| return True |
| del path[-1] |
| return False |
| |
| |
| ############################################################################### |
| |
| # Roundtrip code |
| |
| # Always represent things consistently: |
| |
| yaml.RoundTripRepresenter.add_representer(OrderedDict, |
| yaml.SafeRepresenter.represent_dict) |
| |
| # Always parse things consistently |
| |
| yaml.RoundTripConstructor.add_constructor(u'tag:yaml.org,2002:int', |
| yaml.RoundTripConstructor.construct_yaml_str) |
| yaml.RoundTripConstructor.add_constructor(u'tag:yaml.org,2002:float', |
| yaml.RoundTripConstructor.construct_yaml_str) |
| yaml.RoundTripConstructor.add_constructor(u'tag:yaml.org,2002:bool', |
| yaml.RoundTripConstructor.construct_yaml_str) |
| yaml.RoundTripConstructor.add_constructor(u'tag:yaml.org,2002:null', |
| yaml.RoundTripConstructor.construct_yaml_str) |
| yaml.RoundTripConstructor.add_constructor(u'tag:yaml.org,2002:timestamp', |
| yaml.RoundTripConstructor.construct_yaml_str) |
| |
| |
| # HardlineDumper |
| # |
| # This is a dumper used during roundtrip_dump which forces every scalar to be |
| # a plain string, in order to match the output format to the input format. |
| # |
| # If you discover something is broken, please add a test case to the roundtrip |
| # test in tests/internals/yaml/roundtrip-test.yaml |
| # |
| class HardlineDumper(yaml.RoundTripDumper): |
| def __init__(self, *args, **kwargs): |
| yaml.RoundTripDumper.__init__(self, *args, **kwargs) |
| # For each of YAML 1.1 and 1.2, force everything to be a plain string |
| for version in [(1, 1), (1, 2), None]: |
| self.add_version_implicit_resolver( |
| version, |
| u'tag:yaml.org,2002:str', |
| yaml.util.RegExp(r'.*'), |
| None) |
| |
| |
| # roundtrip_load() |
| # |
| # Load a YAML file into memory in a form which allows roundtripping as best |
| # as ruamel permits. |
| # |
| # Note, the returned objects can be treated as Mappings and Lists and Strings |
| # but replacing content wholesale with plain dicts and lists may result |
| # in a loss of comments and formatting. |
| # |
| # Args: |
| # filename (str): The file to load in |
| # allow_missing (bool): Optionally set this to True to allow missing files |
| # |
| # Returns: |
| # (Mapping): The loaded YAML mapping. |
| # |
| # Raises: |
| # (LoadError): If the file is missing, or a directory, this is raised. |
| # Also if the YAML is malformed. |
| # |
| def roundtrip_load(filename, *, allow_missing=False): |
| try: |
| with open(filename, "r") as fh: |
| data = fh.read() |
| contents = roundtrip_load_data(data, filename=filename) |
| except FileNotFoundError as e: |
| if allow_missing: |
| # Missing files are always empty dictionaries |
| return {} |
| else: |
| raise LoadError(LoadErrorReason.MISSING_FILE, |
| "Could not find file at {}".format(filename)) from e |
| except IsADirectoryError as e: |
| raise LoadError(LoadErrorReason.LOADING_DIRECTORY, |
| "{} is a directory." |
| .format(filename)) from e |
| return contents |
| |
| |
| # roundtrip_load_data() |
| # |
| # Parse the given contents as YAML, returning them as a roundtrippable data |
| # structure. |
| # |
| # A lack of content will be returned as an empty mapping. |
| # |
| # Args: |
| # contents (str): The contents to be parsed as YAML |
| # filename (str): Optional filename to be used in error reports |
| # |
| # Returns: |
| # (Mapping): The loaded YAML mapping |
| # |
| # Raises: |
| # (LoadError): Raised on invalid YAML, or YAML which parses to something other |
| # than a Mapping |
| # |
| def roundtrip_load_data(contents, *, filename=None): |
| try: |
| contents = yaml.load(contents, yaml.RoundTripLoader, preserve_quotes=True) |
| except (yaml.scanner.ScannerError, yaml.composer.ComposerError, yaml.parser.ParserError) as e: |
| raise LoadError(LoadErrorReason.INVALID_YAML, |
| "Malformed YAML:\n\n{}\n\n{}\n".format(e.problem, e.problem_mark)) from e |
| |
| # Special case empty files at this point |
| if contents is None: |
| # We'll make them empty mappings like the main Node loader |
| contents = {} |
| |
| if not isinstance(contents, Mapping): |
| raise LoadError(LoadErrorReason.INVALID_YAML, |
| "YAML file has content of type '{}' instead of expected type 'dict': {}" |
| .format(type(contents).__name__, filename)) |
| |
| return contents |
| |
| |
| # roundtrip_dump() |
| # |
| # Dumps the given contents as a YAML file. Ideally the contents came from |
| # parsing with `roundtrip_load` or `roundtrip_load_data` so that they will be |
| # dumped in the same form as they came from. |
| # |
| # If `file` is a string, it is the filename to write to, if `file` has a |
| # `write` method, it's treated as a stream, otherwise output is to stdout. |
| # |
| # Args: |
| # contents (Mapping or list): The content to write out as YAML. |
| # file (any): The file to write to |
| # |
| def roundtrip_dump(contents, file=None): |
| assert type(contents) is not Node |
| |
| def stringify_dict(thing): |
| for k, v in thing.items(): |
| if type(v) is str: |
| pass |
| elif isinstance(v, Mapping): |
| stringify_dict(v) |
| elif isinstance(v, Sequence): |
| stringify_list(v) |
| else: |
| thing[k] = str(v) |
| |
| def stringify_list(thing): |
| for i, v in enumerate(thing): |
| if type(v) is str: |
| pass |
| elif isinstance(v, Mapping): |
| stringify_dict(v) |
| elif isinstance(v, Sequence): |
| stringify_list(v) |
| else: |
| thing[i] = str(v) |
| |
| contents = deepcopy(contents) |
| stringify_dict(contents) |
| |
| with ExitStack() as stack: |
| if type(file) is str: |
| from . import utils |
| f = stack.enter_context(utils.save_file_atomic(file, 'w')) |
| elif hasattr(file, 'write'): |
| f = file |
| else: |
| f = sys.stdout |
| yaml.round_trip_dump(contents, f, Dumper=HardlineDumper) |
