WIP: Allow running bst commands from worksapce directorychandan/bst-from-workspace

4 files changed, 87 insertions, 16 deletions

diff --git a/buildstream/_context.py b/buildstream/_context.py
index 1a59af2b9..62a67cb8f 100644
--- a/buildstream/_context.py
+++ b/buildstream/_context.py
@@ -104,9 +104,6 @@ class Context():
         # Whether elements must be rebuilt when their dependencies have changed
         self._strict_build_plan = None
 
-        # Make sure the XDG vars are set in the environment before loading anything
-        self._init_xdg()
-
         # Private variables
         self._cache_key = None
         self._message_handler = None
@@ -412,15 +409,3 @@ class Context():
     def _pop_message_depth(self):
         assert self._message_depth
         self._message_depth.popleft()
-
-    # Force the resolved XDG variables into the environment,
-    # this is so that they can be used directly to specify
-    # preferred locations of things from user configuration
-    # files.
-    def _init_xdg(self):
-        if not os.environ.get('XDG_CACHE_HOME'):
-            os.environ['XDG_CACHE_HOME'] = os.path.expanduser('~/.cache')
-        if not os.environ.get('XDG_CONFIG_HOME'):
-            os.environ['XDG_CONFIG_HOME'] = os.path.expanduser('~/.config')
-        if not os.environ.get('XDG_DATA_HOME'):
-            os.environ['XDG_DATA_HOME'] = os.path.expanduser('~/.local/share')
diff --git a/buildstream/_frontend/app.py b/buildstream/_frontend/app.py
index 4675b0eb0..1158e3997 100644
--- a/buildstream/_frontend/app.py
+++ b/buildstream/_frontend/app.py
@@ -123,6 +123,9 @@ class App():
             # Set soft limit to hard limit
             resource.setrlimit(resource.RLIMIT_NOFILE, (limits[1], limits[1]))
 
+        # Make sure the XDG vars are set in the environment before loading anything
+        self._init_xdg()
+
     # create()
     #
     # Should be used instead of the regular constructor.
@@ -811,6 +814,18 @@ class App():
 
         return (project_name, format_version, element_path)
 
+    # Force the resolved XDG variables into the environment,
+    # this is so that they can be used directly to specify
+    # preferred locations of things from user configuration
+    # files.
+    def _init_xdg(self):
+        if not os.environ.get('XDG_CACHE_HOME'):
+            os.environ['XDG_CACHE_HOME'] = os.path.expanduser('~/.cache')
+        if not os.environ.get('XDG_CONFIG_HOME'):
+            os.environ['XDG_CONFIG_HOME'] = os.path.expanduser('~/.config')
+        if not os.environ.get('XDG_DATA_HOME'):
+            os.environ['XDG_DATA_HOME'] = os.path.expanduser('~/.local/share')
+
 
 #
 # Return a value processor for partial choice matching.
diff --git a/buildstream/_project.py b/buildstream/_project.py
index b568cf852..fe55df343 100644
--- a/buildstream/_project.py
+++ b/buildstream/_project.py
@@ -459,7 +459,9 @@ class Project():
     # _ensure_project_dir()
     #
     # Returns path of the project directory, if a configuration file is found
-    # in given directory or any of its parent directories.
+    # in given directory or any of its parent directories.  If current
+    # directory has a workspace associated with it, try to find the
+    # corresponding project
     #
     # Args:
     #    directory (str) - directory from where the command was invoked
@@ -469,6 +471,11 @@ class Project():
     #
     def _ensure_project_dir(self, directory):
         directory = os.path.abspath(directory)
+
+        workspaced_project = self._get_project_from_workspace()
+        if workspaced_project is not None:
+            return workspaced_project
+
         while not os.path.isfile(os.path.join(directory, _PROJECT_CONF_FILE)):
             parent_dir = os.path.dirname(directory)
             if directory == parent_dir:
@@ -479,3 +486,15 @@ class Project():
             directory = parent_dir
 
         return directory
+
+    def _get_project_from_workspace(self):
+        workspaces_file = os.path.join(os.environ['XDG_DATA_HOME'],
+                                       'buildstream', 'workspaces.yml')
+        if not os.path.isfile(workspaces_file):
+            return
+        workspaces = _yaml.load(workspaces_file)
+        fullpath = os.path.realpath(os.getcwd())
+        try:
+            return workspaces['workspaces'][fullpath]['project']
+        except KeyError:
+            return None
diff --git a/buildstream/_workspaces.py b/buildstream/_workspaces.py
index 3f474b8ca..7b219240d 100644
--- a/buildstream/_workspaces.py
+++ b/buildstream/_workspaces.py
@@ -214,7 +214,9 @@ class Workspaces():
     def __init__(self, toplevel_project):
         self._toplevel_project = toplevel_project
         self._bst_directory = os.path.join(toplevel_project.directory, ".bst")
+        self._local_data_directory = os.path.join(os.environ['XDG_DATA_HOME'], 'buildstream')
         self._workspaces = self._load_config()
+        self._workspace_mapping = self._load_local_config()
 
     # list()
     #
@@ -309,6 +311,24 @@ class Workspaces():
         _yaml.dump(_yaml.node_sanitize(config),
                    self._get_filename())
 
+        self._save_local_config()
+
+    # _save_local_config()
+    #
+    # Edit local workspace config in round-trip manner since this file
+    # is shared by all projects.
+    #
+    def _save_local_config(self):
+        workspaces = self._load_local_config()
+        for element, workspace in self._workspaces.items():
+            workspaces[workspace.path] = {'project': self._toplevel_project.directory,
+                                          'element': element}
+        config = {'workspaces': workspaces}
+        os.makedirs(self._local_data_directory, exist_ok=True)
+        _yaml.dump(_yaml.node_sanitize(config),
+                   self._get_local_filename())
+
+
     # _load_config()
     #
     # Loads and parses the workspace configuration
@@ -331,6 +351,29 @@ class Workspaces():
 
         return self._parse_workspace_config(node)
 
+
+    # _load_local_config()
+    #
+    # Loads and parses the workspace configuration
+    #
+    # Returns:
+    #    (dict) The extracted workspaces
+    #
+    # Raises: LoadError if there was a problem with the workspace config
+    #
+    def _load_local_config(self):
+        workspace_file = self._get_local_filename()
+        try:
+            node = _yaml.load(workspace_file)
+        except LoadError as e:
+            if e.reason == LoadErrorReason.MISSING_FILE:
+                # Return an empty dict if there was no workspace file
+                return {}
+
+            raise
+
+        return _yaml.node_get(node, dict, "workspaces", default_value={})
+
     # _parse_workspace_config_format()
     #
     # If workspace config is in old-style format, i.e. it is using
@@ -414,3 +457,12 @@ class Workspaces():
     #    (str): The path to workspaces.yml file.
     def _get_filename(self):
         return os.path.join(self._bst_directory, "workspaces.yml")
+
+    # _get_local_filename():
+    #
+    # Get the workspaces.yml file path.
+    #
+    # Returns:
+    #    (str): The path to workspaces.yml file.
+    def _get_local_filename(self):
+        return os.path.join(self._local_data_directory, 'workspaces.yml')