[Notes] [Git][BuildStream/buildstream][jonathan/pickle-yaml] 2 commits:

Jonathan Maw pushed to branch jonathan/pickle-yaml at BuildStream / buildstream

Commits:

81672b05

by Jonathan Maw at 2018-09-14T15:35:59Z

Loader: Make _extract_depends_from_node not 'del' nonexistent fields

This is benign because a _yaml.ChainMap doesn't raise a
KeyError, but it's not required to be a ChainMap.

1d02b329

by Jonathan Maw at 2018-09-14T17:17:52Z

Add a cache of parsed and provenanced yaml

Note that the ProvenanceFile's names will be incorrect after loading
from the cache, but this is currently only used for writeback, which
isn't used in junctions.

5 changed files:

buildstream/_loader/loadelement.py
buildstream/_loader/loader.py
+ buildstream/_pickler.py
buildstream/_project.py
buildstream/_yaml.py

Changes:

buildstream/_loader/loadelement.py

@@ -185,6 +185,6 @@ def _extract_depends_from_node(node, *, key=None):
          output_deps.append(dependency)
      # Now delete the field, we dont want it anymore
 -    del node[key]
 +    node.pop(key, None)
      return output_deps

buildstream/_loader/loader.py

@@ -30,6 +30,7 @@ from ..element import Element
  from .._profile import Topics, profile_start, profile_end
  from .._platform import Platform
  from .._includes import Includes
 +from .._pickler import YamlCache
  from .types import Symbol, Dependency
  from .loadelement import LoadElement
@@ -113,7 +114,8 @@ class Loader():
              profile_start(Topics.LOAD_PROJECT, target)
              junction, name, loader = self._parse_name(target, rewritable, ticker,
                                                        fetch_subprojects=fetch_subprojects)
 -            loader._load_file(name, rewritable, ticker, fetch_subprojects)
 +            with YamlCache.get_cache(self._context) as yaml_cache:
 +                loader._load_file(name, rewritable, ticker, fetch_subprojects, yaml_cache)
              deps.append(Dependency(name, junction=junction))
              profile_end(Topics.LOAD_PROJECT, target)
@@ -202,11 +204,12 @@ class Loader():
      #    rewritable (bool): Whether we should load in round trippable mode
      #    ticker (callable): A callback to report loaded filenames to the frontend
      #    fetch_subprojects (bool): Whether to fetch subprojects while loading
 +    #    yaml_cache (YamlCache): A yaml cache
+     #
      # Returns:
      #    (LoadElement): A loaded LoadElement
+     #
 -    def _load_file(self, filename, rewritable, ticker, fetch_subprojects):
 +    def _load_file(self, filename, rewritable, ticker, fetch_subprojects, yaml_cache=None):
          # Silently ignore already loaded files
          if filename in self._elements:
@@ -219,7 +222,8 @@ class Loader():
          # Load the data and process any conditional statements therein
          fullpath = os.path.join(self._basedir, filename)
          try:
 -            node = _yaml.load(fullpath, shortname=filename, copy_tree=rewritable, project=self.project)
 +            node = _yaml.load(fullpath, shortname=filename, copy_tree=rewritable,
 +                              project=self.project, yaml_cache=yaml_cache)
          except LoadError as e:
              if e.reason == LoadErrorReason.MISSING_FILE:
                  # If we can't find the file, try to suggest plausible
@@ -262,13 +266,13 @@ class Loader():
          # Load all dependency files for the new LoadElement
          for dep in element.deps:
              if dep.junction:
 -                self._load_file(dep.junction, rewritable, ticker, fetch_subprojects)
 +                self._load_file(dep.junction, rewritable, ticker, fetch_subprojects, yaml_cache)
                  loader = self._get_loader(dep.junction, rewritable=rewritable, ticker=ticker,
                                            fetch_subprojects=fetch_subprojects)
              else:
                  loader = self
 -            dep_element = loader._load_file(dep.name, rewritable, ticker, fetch_subprojects)
 +            dep_element = loader._load_file(dep.name, rewritable, ticker, fetch_subprojects, yaml_cache)
              if _yaml.node_get(dep_element.node, str, Symbol.KIND) == 'junction':
                  raise LoadError(LoadErrorReason.INVALID_DATA,

buildstream/_pickler.py

 +#
 +#  Copyright 2018 Bloomberg Finance LP
 +#
 +#  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:
 +#        Jonathan Maw <jonathan maw codethink co uk>
++
 +import os
 +import pickle
 +import hashlib
 +import io
++
 +from contextlib import contextmanager
 +from collections import namedtuple
++
 +from ._cachekey import generate_key
 +from . import utils, _yaml
++
++
 +YAML_CACHE_FILENAME = "yaml_cache.pickle"
++
++
 +# In _yaml.load, we have a ProvenanceFile that stores the project the file
 +# came from. Projects can't be pickled, but it's always going to be the same
 +# project between invocations (unless the entire project is moved but the
 +# file stayed in the same place)
 +class BstPickler(pickle.Pickler):
 +    def persistent_id(self, obj):
 +        if isinstance(obj, _yaml.ProvenanceFile):
 +            if obj.project:
 +                # ProvenanceFile's project object cannot be stored as it is.
 +                project_tag = obj.project.name
 +                # ProvenanceFile's filename must be stored relative to the
 +                # project, as the project dir may move.
 +                name = os.path.relpath(obj.name, obj.project.directory)
 +            else:
 +                project_tag = None
 +                name = obj.name
 +            return ("ProvenanceFile", name, obj.shortname, project_tag)
 +        else:
 +            return None
++
 +    @staticmethod
 +    def dumps(obj):
 +        stream = io.BytesIO()
 +        BstPickler(stream).dump(obj)
 +        stream.seek(0)
 +        return stream.read()
++
++
 +class BstUnpickler(pickle.Unpickler):
 +    def __init__(self, file, context):
 +        super().__init__(file)
 +        self._context = context
++
 +    def persistent_load(self, pid):
 +        if pid[0] == "ProvenanceFile":
 +            _, tagged_name, shortname, project_tag = pid
++
 +            if project_tag is not None:
 +                for p in self._context.get_projects():
 +                    if project_tag == p.name:
 +                        project = p
 +                        break
++
 +                name = os.path.join(project.directory, tagged_name)
++
 +                if not project:
 +                    projects = [p.name for p in self._context.get_projects()]
 +                    raise pickle.UnpicklingError("No project with name {} found in {}"
 +                                                 .format(key_id, projects))
 +            else:
 +                project = None
 +                name = tagged_name
++
 +            return _yaml.ProvenanceFile(name, shortname, project)
++
 +        else:
 +            raise pickle.UnpicklingError("Unsupported persistent object")
++
 +    @staticmethod
 +    def loads(text, context):
 +        stream = io.BytesIO()
 +        stream.write(bytes(text))
 +        stream.seek(0)
 +        return BstUnpickler(stream, context).load()
++
++
 +CachedProject = namedtuple('CachedProject', ['path', 'project_sum', 'elements'])
++
++
 +class CachedYaml():
 +    def __init__(self, key, contents):
 +        self._key = key
 +        self.set_contents(contents)
++
 +    # Sets the contents of the CachedYaml.
 +    #
 +    # Args:
 +    #    contents (provenanced dict): The contents to put in the cache.
 +    #
 +    def set_contents(self, contents):
 +        self._contents = contents
 +        self._pickled_contents = BstPickler.dumps(contents)
++
 +    # Pickling helper method, prevents 'contents' from being serialised
 +    def __getstate__(self):
 +        data = self.__dict__.copy()
 +        data['_contents'] = None
 +        return data
++
++
 +class YamlCache():
++
 +    def __init__(self):
 +        self._project_caches = {}
++
 +    # Writes the yaml cache to the specified path.
 +    #
 +    # Args:
 +    #    path (str): The file to write the cache to.
 +    #
 +    def write(self, path):
 +        parent_dir = os.path.dirname(path)
 +        os.makedirs(parent_dir, exist_ok=True)
 +        with open(path, "wb") as f:
 +            BstPickler(f).dump(self)
++
 +    # Gets a parsed file from the cache.
 +    #
 +    # Args:
 +    #    project (Project): The project this file is in.
 +    #    filepath (str): The path to the file, *relative to the project's directory*.
 +    #    key (str): The key to the file within the cache. Typically, this is the
 +    #               value of `calculate_key()` with the file's unparsed contents
 +    #               and any relevant metadata passed in.
 +    #
 +    # Returns:
 +    #    (decorated dict): The parsed yaml from the cache, or None if the file isn't in the cache.
 +    def get(self, project, filepath, key):
 +        if project.name in self._project_caches:
 +            project_cache = self._project_caches[project.name]
 +            if filepath in project_cache.elements:
 +                cachedyaml = project_cache.elements[filepath]
 +                if cachedyaml._key == key:
 +                    if cachedyaml._contents is None:
 +                        cachedyaml._contents = BstUnpickler.loads(cachedyaml._pickled_contents, project._context)
 +                    return cachedyaml._contents
 +        return None
++
 +    # Put a parsed file into the cache.
 +    #
 +    # Args:
 +    #    project (Project): The project this file is in.
 +    #    filepath (str): The path to the file, *relative to the project's directory*.
 +    #    key (str): The key to the file within the cache. Typically, this is the
 +    #               value of `calculate_key()` with the file's unparsed contents
 +    #               and any relevant metadata passed in.
 +    #    value (decorated dict): The data to put into the cache.
 +    def put(self, project, filepath, key, value):
 +        if project.name in self._project_caches \
 +                and project.shasum == self._project_caches[project.name].project_sum:
 +            project_cache = self._project_caches[project.name]
 +        else:
 +            project_cache = self._project_caches[project.name] = CachedProject(project.directory, project.shasum, {})
++
 +        project_cache.elements[filepath] = CachedYaml(key, value)
++
 +    # Return an instance of the YamlCache which writes to disk when it leaves scope.
 +    #
 +    # Args:
 +    #    context (Context): The context.
 +    #
 +    # Returns:
 +    #    (YamlCache): A YamlCache.
 +    @staticmethod
 +    @contextmanager
 +    def get_cache(context):
 +        # Try to load from disk first
 +        cachefile = YamlCache._get_cache_file(context)
 +        cache = None
 +        if os.path.exists(cachefile):
 +            try:
 +                with open(cachefile, "rb") as f:
 +                    cache = BstUnpickler(f, context).load()
 +            except pickle.UnpicklingError as e:
 +                pass
++
 +        if not cache:
 +            cache = YamlCache()
++
 +        yield cache
++
 +        cache.write(cachefile)
++
 +    # Calculates a key for putting into the cache.
 +    @staticmethod
 +    def calculate_key(*args):
 +        string = pickle.dumps(args)
 +        return hashlib.sha1(string).hexdigest()
++
 +    # Retrieves a path to the yaml cache file.
 +    @staticmethod
 +    def _get_cache_file(context):
 +        toplevel_project = context.get_toplevel_project()
 +        return os.path.join(toplevel_project.directory, ".bst", YAML_CACHE_FILENAME)

buildstream/_project.py

@@ -19,6 +19,7 @@
  #        Tiago Gomes <tiago gomes codethink co uk>
  import os
 +import hashlib
  from collections import Mapping, OrderedDict
  from pluginbase import PluginBase
  from . import utils
@@ -110,6 +111,7 @@ class Project():
          self.ref_storage = None                  # ProjectRefStorage setting
          self.base_environment = {}               # The base set of environment variables
          self.base_env_nocache = None             # The base nocache mask (list) for the environment
 +        self.shasum = None                       # A SHA-1 sum of the project file
+         #
          # Private Members
@@ -382,6 +384,10 @@ class Project():
          # Load project local config and override the builtin
          try:
 +            with open(projectfile, "r") as f:
 +                contents = f.read()
 +            self.shasum = hashlib.sha1(contents.encode('utf-8')).hexdigest()
++
              self._project_conf = _yaml.load(projectfile)
          except LoadError as e:
              # Raise a more specific error here

buildstream/_yaml.py

@@ -23,6 +23,8 @@ import string
  from copy import deepcopy
  from contextlib import ExitStack
  from pathlib import Path
 +import hashlib
 +import os
  from ruamel import yaml
  from ruamel.yaml.representer import SafeRepresenter, RoundTripRepresenter
@@ -183,12 +185,13 @@ class CompositeTypeError(CompositeError):
  #    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
 +#    yaml_cache (YamlCache): A yaml cache to consult rather than parsing
+ #
  # Returns (dict): A loaded copy of the YAML file with provenance information
+ #
  # Raises: LoadError
+ #
 -def load(filename, shortname=None, copy_tree=False, *, project=None):
 +def load(filename, shortname=None, copy_tree=False, *, project=None, yaml_cache=None):
      if not shortname:
          shortname = filename
@@ -196,7 +199,7 @@ def load(filename, shortname=None, copy_tree=False, *, project=None):
      try:
          with open(filename) as f:
 -            return load_data(f, file, copy_tree=copy_tree)
 +            return load_data(f, file, copy_tree=copy_tree, yaml_cache=yaml_cache)
      except FileNotFoundError as e:
          raise LoadError(LoadErrorReason.MISSING_FILE,
                          "Could not find file at {}".format(filename)) from e
@@ -208,24 +211,46 @@ def load(filename, shortname=None, copy_tree=False, *, project=None):
  # Like load(), but doesnt require the data to be in a file
+ #
 -def load_data(data, file=None, copy_tree=False):
 +def load_data(data, file=None, copy_tree=False, yaml_cache=None):
 -    try:
 -        contents = yaml.load(data, yaml.loader.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
+-
 -    if not isinstance(contents, dict):
 -        # Special case allowance for None, when the loaded file has only comments in it.
 -        if contents is None:
 -            contents = {}
 -        else:
 +    if hasattr(data, 'read'):
 +        file_contents = data.read()
 +    else:
 +        file_contents = data
 +    # Forced to compare sums of contents because elements in junctions are stored in tmpdirs
 +    decorated_yaml = None
 +    if yaml_cache:
 +        assert file
 +        project = file.project
 +        filename = os.path.relpath(file.name, project.directory)
 +        key = yaml_cache.calculate_key(file_contents, copy_tree)
 +        decorated_yaml = yaml_cache.get(project, filename, key)
++
 +    if not decorated_yaml:
 +        try:
 +            contents = yaml.load(file_contents, yaml.loader.RoundTripLoader, preserve_quotes=True)
 +        except (yaml.scanner.ScannerError, yaml.composer.ComposerError, yaml.parser.ParserError) as e:
              raise LoadError(LoadErrorReason.INVALID_YAML,
 -                            "YAML file has content of type '{}' instead of expected type 'dict': {}"
 -                            .format(type(contents).__name__, file.name))
 +                            "Malformed YAML:\n\n{}\n\n{}\n".format(e.problem, e.problem_mark)) from e
 -    return node_decorated_copy(file, contents, copy_tree=copy_tree)
 +        if not isinstance(contents, dict):
 +            # Special case allowance for None, when the loaded file has only comments in it.
 +            if contents is None:
 +                contents = {}
 +            else:
 +                raise LoadError(LoadErrorReason.INVALID_YAML,
 +                                "YAML file has content of type '{}' instead of expected type 'dict': {}"
 +                                .format(type(contents).__name__, file.name))
++
 +        decorated_yaml = node_decorated_copy(file, contents, copy_tree=copy_tree)
 +        if yaml_cache:
 +            assert file
 +            project = file.project
 +            filename = os.path.relpath(file.name, project.directory)
 +            key = yaml_cache.calculate_key(file_contents, copy_tree)
 +            yaml_cache.put(project, filename, key, decorated_yaml)
++
 +    return decorated_yaml
  # Dumps a previously loaded YAML node to a file

[Notes] [Git][BuildStream/buildstream][jonathan/pickle-yaml] 2 commits: Loader: Make _extract_depends_from_node not 'del' nonexistent fields

Jonathan Maw pushed to branch jonathan/pickle-yaml at BuildStream / buildstream

Commits:

5 changed files:

Changes: