Refactor: Move context.py -> _context.py

Consequently:

  o Changed Plugin.get_context() to a private Plugin._get_context() accessor.

  o Updated anything which imports Context to do so from private _context module

  o Updated docs to exclude the now private Context

16 files changed, 74 insertions, 84 deletions

diff --git a/buildstream/__init__.py b/buildstream/__init__.py
index b3751a6e3..cde1b43e5 100644
--- a/buildstream/__init__.py
+++ b/buildstream/__init__.py
@@ -18,11 +18,8 @@
 #  Authors:
 #        Tristan Van Berkom <tristan.vanberkom@codethink.co.uk>
 
-# Core components
-from .context import Context
-from .sandbox import Sandbox, SandboxFlags
-
 # Plugin auther facing APIs
+from .sandbox import Sandbox, SandboxFlags
 from .plugin import Plugin
 from .source import Source, SourceError, Consistency
 from .element import Element, ElementError, Scope
diff --git a/buildstream/context.py b/buildstream/_context.py
index 81929591a..f85771bac 100644
--- a/buildstream/context.py
+++ b/buildstream/_context.py
@@ -18,20 +18,6 @@
 #  Authors:
 #        Tristan Van Berkom <tristan.vanberkom@codethink.co.uk>
 
-"""
-Context
-=======
-
-The :class:`.Context` object holds all of the user preferences
-and context for a given invocation of BuildStream.
-
-This is a collection of data from configuration files and command
-line arguments and consists of information such as where to store
-logs and artifacts, where to perform builds and cache downloaded sources,
-verbosity levels and basically anything pertaining to the context
-in which BuildStream was invoked.
-"""
-
 import os
 import hashlib
 import pickle
@@ -43,72 +29,80 @@ from ._exceptions import LoadError, LoadErrorReason
 from ._profile import Topics, profile_start, profile_end
 
 
+# Context()
+#
+# The Context object holds all of the user preferences
+# and context for a given invocation of BuildStream.
+#
+# This is a collection of data from configuration files and command
+# line arguments and consists of information such as where to store
+# logs and artifacts, where to perform builds and cache downloaded sources,
+# verbosity levels and basically anything pertaining to the context
+# in which BuildStream was invoked.
+#
 class Context():
-    """Context()
 
-    Context of how BuildStream was invoked
-    """
     def __init__(self, cli_options):
 
+        # Filename indicating which configuration file was used, or None for the defaults
         self.config_origin = None
-        """Filename indicating which configuration file was used, or None for the defaults"""
 
+        # Whether elements must be rebuilt when their dependencies have changed
         self.strict_build_plan = None
-        """Whether elements must be rebuilt when their dependencies have changed"""
 
+        # The directory where various sources are stored
         self.sourcedir = None
-        """The directory where various sources are stored"""
 
+        # The directory where build sandboxes will be created
         self.builddir = None
-        """The directory where build sandboxes will be created"""
 
+        # The local binary artifact cache directory
         self.artifactdir = None
-        """The local binary artifact cache directory"""
 
+        # The URL from which to download prebuilt artifacts
         self.artifact_pull = None
-        """The URL from which to download prebuilt artifacts"""
 
+        # The URL to upload built artifacts to
         self.artifact_push = None
-        """The URL to upload built artifacts to"""
 
+        # The port number for pushing artifacts over ssh
         self.artifact_push_port = 22
-        """The port number for pushing artifacts over ssh"""
 
+        # The directory to store build logs
         self.logdir = None
-        """The directory to store build logs"""
 
+        # The abbreviated cache key length to display in the UI
         self.log_key_length = 0
-        """The abbreviated cache key length to display in the UI"""
 
+        # Whether debug mode is enabled
         self.log_debug = False
-        """Whether debug mode is enabled"""
 
+        # Whether verbose mode is enabled
         self.log_verbose = False
-        """Whether verbose mode is enabled"""
 
+        # Maximum number of lines to print from build logs
         self.log_error_lines = 0
-        """Maximum number of lines to print from build logs"""
 
+        # Maximum number of lines to print in the master log for a detailed message
         self.log_message_lines = 0
-        """Maximum number of lines to print in the master log for a detailed message"""
 
+        # Format string for printing the pipeline at startup time
         self.log_element_format = None
-        """Format string for printing the pipeline at startup time"""
 
+        # Maximum number of fetch or refresh tasks
         self.sched_fetchers = 4
-        """Maximum number of fetch or refresh tasks"""
 
+        # Maximum number of build tasks
         self.sched_builders = 4
-        """Maximum number of build tasks"""
 
+        # Maximum number of push tasks
         self.sched_pushers = 4
-        """Maximum number of push tasks"""
 
+        # Maximum number of retries for network tasks
         self.sched_network_retries = 2
-        """Maximum number of retries for network tasks"""
 
+        # What to do when a build fails in non interactive mode
         self.sched_error_action = 'continue'
-        """What to do when a build fails in non interactive mode"""
 
         # Make sure the XDG vars are set in the environment before loading anything
         self._init_xdg()
@@ -121,19 +115,21 @@ class Context():
         self._project_overrides = {}
         self._cli_options = cli_options
 
+    # load()
+    #
+    # Loads the configuration files
+    #
+    # Args:
+    #    config (filename): The user specified configuration file, if any
+    #
+    # Raises:
+    #   LoadError
+    #
+    # This will first load the BuildStream default configuration and then
+    # override that configuration with the configuration file indicated
+    # by *config*, if any was specified.
+    #
     def load(self, config=None):
-        """Loads the configuration files
-
-        Args:
-           config (filename): The user specified configuration file, if any
-
-        Raises:
-           :class:`.LoadError`
-
-        This will first load the BuildStream default configuration and then
-        override that configuration with the configuration file indicated
-        by *config*, if any was specified.
-        """
         profile_start(Topics.LOAD_CONTEXT, 'load')
 
         # If a specific config file is not specified, default to trying
@@ -218,10 +214,6 @@ class Context():
                             "{}: on-error should be one of: {}".format(
                                 provenance, ", ".join(valid_actions)))
 
-    #############################################################
-    #            Private Methods used in BuildStream            #
-    #############################################################
-
     # _get_overrides():
     #
     # Fetch the override dictionary for the active project. This returns
diff --git a/buildstream/_frontend/main.py b/buildstream/_frontend/main.py
index c2002654c..4e00a2be1 100644
--- a/buildstream/_frontend/main.py
+++ b/buildstream/_frontend/main.py
@@ -25,9 +25,10 @@ from contextlib import contextmanager
 from blessings import Terminal
 
 # Import buildstream public symbols
-from .. import Context, Scope, Consistency
+from .. import Scope, Consistency
 
 # Import various buildstream internals
+from .._context import Context
 from .._project import Project
 from .._exceptions import BstError, LoadError
 from .._message import MessageType, unconditional_messages
diff --git a/buildstream/_pipeline.py b/buildstream/_pipeline.py
index 90ed899ea..febadbcc7 100644
--- a/buildstream/_pipeline.py
+++ b/buildstream/_pipeline.py
@@ -829,7 +829,7 @@ class Pipeline():
         # bound.
 
         # Create a temporary directory to build the source tree in
-        builddir = target.get_context().builddir
+        builddir = target._get_context().builddir
         prefix = "{}-".format(target.normal_name)
 
         with TemporaryDirectory(prefix=prefix, dir=builddir) as tempdir:
diff --git a/buildstream/_scheduler/trackqueue.py b/buildstream/_scheduler/trackqueue.py
index 3159a3adc..df73a7280 100644
--- a/buildstream/_scheduler/trackqueue.py
+++ b/buildstream/_scheduler/trackqueue.py
@@ -80,7 +80,7 @@ class TrackQueue(Queue):
         # tracking, this is avoid a following fetch queue operating on the sources
         # if the tracked ref is cached as a result.
         #
-        context = element.get_context()
+        context = element._get_context()
         context._push_message_depth(True)
         element._consistency(recalculate=True)
         context._pop_message_depth()
diff --git a/buildstream/element.py b/buildstream/element.py
index 86dd2b8dc..22a2ebdbb 100644
--- a/buildstream/element.py
+++ b/buildstream/element.py
@@ -855,7 +855,7 @@ class Element(Plugin):
             if key not in self.__env_nocache
         }
 
-        context = self.get_context()
+        context = self._get_context()
         project = self._get_project()
         return utils._generate_key({
             'artifact-version': "{}.{}".format(BST_CORE_ARTIFACT_VERSION,
@@ -969,7 +969,7 @@ class Element(Plugin):
     # Question marks are returned if information for the cache key is missing.
     #
     def _get_full_display_key(self):
-        context = self.get_context()
+        context = self._get_context()
         cache_key = None
         dim_key = True
 
@@ -1038,7 +1038,7 @@ class Element(Plugin):
         # Assert call ordering
         assert(not self._cached())
 
-        context = self.get_context()
+        context = self._get_context()
         with self._output_file() as output_file:
 
             # Explicitly clean it up, keep the build dir around if exceptions are raised
@@ -1203,7 +1203,7 @@ class Element(Plugin):
     #
     def _logfile(self, action_name, pid=None):
         project = self._get_project()
-        context = self.get_context()
+        context = self._get_context()
         key = self._get_display_key()
         if pid is None:
             pid = os.getpid()
@@ -1412,7 +1412,7 @@ class Element(Plugin):
     #
     def _get_strict(self):
         project = self._get_project()
-        context = self.get_context()
+        context = self._get_context()
         return context._get_strict(project.name)
 
     #############################################################
@@ -1420,7 +1420,7 @@ class Element(Plugin):
     #############################################################
     @contextmanager
     def __sandbox(self, directory, stdout=None, stderr=None):
-        context = self.get_context()
+        context = self._get_context()
         project = self._get_project()
         platform = Platform.get_platform()
 
diff --git a/buildstream/plugin.py b/buildstream/plugin.py
index 56bee90c1..5a7d70961 100644
--- a/buildstream/plugin.py
+++ b/buildstream/plugin.py
@@ -176,14 +176,6 @@ class Plugin():
         """
         return self.__kind
 
-    def get_context(self):
-        """Fetches the context
-
-        Returns:
-           (object): The :class:`.Context`
-        """
-        return self.__context
-
     def node_items(self, node):
         """Iterate over a dictionary loaded from YAML
 
@@ -562,6 +554,13 @@ class Plugin():
     #            Private Methods used in BuildStream            #
     #############################################################
 
+    # _get_context()
+    #
+    # Fetches the invocation context
+    #
+    def _get_context(self):
+        return self.__context
+
     # _get_project()
     #
     # Fetches the project object associated with this plugin
diff --git a/buildstream/sandbox/_sandboxchroot.py b/buildstream/sandbox/_sandboxchroot.py
index 20ead6d84..d8da7e3b5 100644
--- a/buildstream/sandbox/_sandboxchroot.py
+++ b/buildstream/sandbox/_sandboxchroot.py
@@ -38,8 +38,6 @@ from . import Sandbox, SandboxFlags
 class SandboxChroot(Sandbox):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-
-        self.platform = self._get_context()._platform
         self.mount_map = None
 
     def run(self, command, flags, cwd=None, env=None):
diff --git a/buildstream/source.py b/buildstream/source.py
index ed9ff3aaa..ed3fe92b3 100644
--- a/buildstream/source.py
+++ b/buildstream/source.py
@@ -99,7 +99,7 @@ class Source(Plugin):
         """
 
         # Create the directory if it doesnt exist
-        context = self.get_context()
+        context = self._get_context()
         directory = os.path.join(context.sourcedir, self.get_kind())
         os.makedirs(directory, exist_ok=True)
         return directory
diff --git a/doc/source/pluginauthoring.rst b/doc/source/pluginauthoring.rst
index 4773c3ea8..ce22d3f32 100644
--- a/doc/source/pluginauthoring.rst
+++ b/doc/source/pluginauthoring.rst
@@ -20,6 +20,5 @@ implement custom :mod:`Element <buildstream.element>` or
 * :mod:`Element <buildstream.element>` - Base Element Class
 * :mod:`BuildElement <buildstream.buildelement>` - Build Element Class
 * :mod:`ScriptElement <buildstream.scriptelement>` - Script Element Class
-* :mod:`Context <buildstream.context>` - Invocation Context
 * :mod:`Sandbox <buildstream.sandbox.sandbox>` - Build Sandbox
 * :mod:`Utilities <buildstream.utils>` - Utilities for Plugins
diff --git a/tests/context/context.py b/tests/context/context.py
index be0dd8a55..0db589a1a 100644
--- a/tests/context/context.py
+++ b/tests/context/context.py
@@ -1,7 +1,7 @@
 import os
 import pytest
 
-from buildstream import Context
+from buildstream._context import Context
 from buildstream._exceptions import LoadError, LoadErrorReason
 
 from tests.testutils.site import HAVE_ROOT
diff --git a/tests/pipeline/load.py b/tests/pipeline/load.py
index a0b6d7ae3..7adcd0f1e 100644
--- a/tests/pipeline/load.py
+++ b/tests/pipeline/load.py
@@ -1,7 +1,8 @@
 import os
 import pytest
 
-from buildstream import Context, Scope
+from buildstream import Scope
+from buildstream._context import Context
 from buildstream._project import Project
 from buildstream._pipeline import Pipeline
 from buildstream._platform import Platform
diff --git a/tests/plugins/pipeline.py b/tests/plugins/pipeline.py
index 6fac82b89..5f1a85e24 100644
--- a/tests/plugins/pipeline.py
+++ b/tests/plugins/pipeline.py
@@ -1,7 +1,8 @@
 import os
 import pytest
 
-from buildstream import Context, Scope
+from buildstream import Scope
+from buildstream._context import Context
 from buildstream._project import Project
 from buildstream._exceptions import PluginError
 from buildstream._pipeline import Pipeline
diff --git a/tests/project/plugins.py b/tests/project/plugins.py
index 424548082..5f7517278 100644
--- a/tests/project/plugins.py
+++ b/tests/project/plugins.py
@@ -1,7 +1,8 @@
 import os
 import pytest
 
-from buildstream import Context, Scope
+from buildstream import Scope
+from buildstream._context import Context
 from buildstream._project import Project
 from buildstream._pipeline import Pipeline
 from buildstream._platform import Platform
diff --git a/tests/project/project.py b/tests/project/project.py
index 32a264c6d..3a1484309 100644
--- a/tests/project/project.py
+++ b/tests/project/project.py
@@ -1,7 +1,7 @@
 import os
 import pytest
 
-from buildstream import Context
+from buildstream._context import Context
 from buildstream._project import Project
 from buildstream._exceptions import LoadError, LoadErrorReason
 
diff --git a/tests/variables/variables.py b/tests/variables/variables.py
index 51af7e27b..7562857f9 100644
--- a/tests/variables/variables.py
+++ b/tests/variables/variables.py
@@ -1,7 +1,8 @@
 import os
 import pytest
 
-from buildstream import Context, BuildElement
+from buildstream import BuildElement
+from buildstream._context import Context
 from buildstream._project import Project
 from buildstream._pipeline import Pipeline
 from buildstream._platform import Platform