Drop Platform subclasses and BST_FORCE_BACKENDjuerg/sandbox-drop-bwrap

With the use of buildbox-run on all platforms, there is no longer any
platform-specific code in the Platform subclasses.

7 files changed, 18 insertions, 184 deletions

diff --git a/src/buildstream/_platform/darwin.py b/src/buildstream/_platform/darwin.py
deleted file mode 100644
index 00bca2c4c..000000000
--- a/src/buildstream/_platform/darwin.py
+++ /dev/null
@@ -1,36 +0,0 @@
-#
-#  Copyright (C) 2017 Codethink Limited
-#  Copyright (C) 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/>.
-
-from ..sandbox import SandboxDummy
-
-from .platform import Platform
-
-
-class Darwin(Platform):
-    @staticmethod
-    def _check_dummy_sandbox_config(config):
-        pass
-
-    @staticmethod
-    def _create_dummy_sandbox(*args, **kwargs):
-        kwargs["dummy_reason"] = "There are no supported sandbox technologies for MacOS at this time"
-        return SandboxDummy(*args, **kwargs)
-
-    def _setup_dummy_sandbox(self):
-        self.check_sandbox_config = Darwin._check_dummy_sandbox_config
-        self.create_sandbox = Darwin._create_dummy_sandbox
-        return True
diff --git a/src/buildstream/_platform/fallback.py b/src/buildstream/_platform/fallback.py
deleted file mode 100644
index d80ac8fde..000000000
--- a/src/buildstream/_platform/fallback.py
+++ /dev/null
@@ -1,37 +0,0 @@
-#
-#  Copyright (C) 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/>.
-
-from ..sandbox import SandboxDummy
-
-from .platform import Platform
-
-
-class Fallback(Platform):
-    def _check_dummy_sandbox_config(self, config):
-        pass
-
-    def _create_dummy_sandbox(self, *args, **kwargs):
-        kwargs["dummy_reason"] = (
-            "FallBack platform only implements dummy sandbox, "
-            "Buildstream may be having issues correctly detecting your platform, "
-            "platform can be forced with BST_FORCE_BACKEND"
-        )
-        return SandboxDummy(*args, **kwargs)
-
-    def _setup_dummy_sandbox(self):
-        self.check_sandbox_config = self._check_dummy_sandbox_config
-        self.create_sandbox = self._create_dummy_sandbox
-        return True
diff --git a/src/buildstream/_platform/linux.py b/src/buildstream/_platform/linux.py
deleted file mode 100644
index c6065b416..000000000
--- a/src/buildstream/_platform/linux.py
+++ /dev/null
@@ -1,45 +0,0 @@
-#
-#  Copyright (C) 2017 Codethink Limited
-#  Copyright (C) 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:
-#        Tristan Maat <tristan.maat@codethink.co.uk>
-
-from ..sandbox import SandboxDummy
-
-from .platform import Platform
-
-
-class Linux(Platform):
-
-    ################################################
-    #              Private Methods                 #
-    ################################################
-
-    # Dummy sandbox methods
-    @staticmethod
-    def _check_dummy_sandbox_config(config):
-        return True
-
-    def _create_dummy_sandbox(self, *args, **kwargs):
-        dummy_reasons = " and ".join(self.dummy_reasons)
-        kwargs["dummy_reason"] = dummy_reasons
-        return SandboxDummy(*args, **kwargs)
-
-    def _setup_dummy_sandbox(self):
-        self.check_sandbox_config = Linux._check_dummy_sandbox_config
-        self.create_sandbox = self._create_dummy_sandbox
-        return True
diff --git a/src/buildstream/_platform/platform.py b/src/buildstream/_platform/platform.py
index 8a1794cbf..f46043cbf 100644
--- a/src/buildstream/_platform/platform.py
+++ b/src/buildstream/_platform/platform.py
@@ -21,11 +21,11 @@
 import multiprocessing
 import os
 import platform
-import sys
 
 import psutil
 
 from .._exceptions import PlatformError, ImplError, SandboxError
+from ..sandbox import SandboxDummy
 from .. import utils
 
 
@@ -58,29 +58,7 @@ class Platform:
 
     @classmethod
     def create_instance(cls):
-        if os.getenv("BST_FORCE_BACKEND"):
-            backend = os.getenv("BST_FORCE_BACKEND")
-        elif sys.platform.startswith("darwin"):
-            backend = "darwin"
-        elif sys.platform.startswith("linux"):
-            backend = "linux"
-        elif sys.platform == "win32":
-            backend = "win32"
-        else:
-            backend = "fallback"
-
-        if backend == "linux":
-            from .linux import Linux as PlatformImpl  # pylint: disable=cyclic-import
-        elif backend == "darwin":
-            from .darwin import Darwin as PlatformImpl  # pylint: disable=cyclic-import
-        elif backend == "win32":
-            from .win32 import Win32 as PlatformImpl  # pylint: disable=cyclic-import
-        elif backend == "fallback":
-            from .fallback import Fallback as PlatformImpl  # pylint: disable=cyclic-import
-        else:
-            raise PlatformError("No such platform: '{}'".format(backend))
-
-        return PlatformImpl()
+        return Platform()
 
     def get_cpu_count(self, cap=None):
         # `psutil.Process.cpu_affinity()` is not available on all platforms.
@@ -204,11 +182,6 @@ class Platform:
             "Platform {platform} does not implement check_sandbox_config()".format(platform=type(self).__name__)
         )
 
-    def _setup_dummy_sandbox(self):
-        raise ImplError(
-            "Platform {platform} does not implement _setup_dummy_sandbox()".format(platform=type(self).__name__)
-        )
-
     # Buildbox run sandbox methods
     def _check_sandbox_config_buildboxrun(self, config):
         from ..sandbox._sandboxbuildboxrun import SandboxBuildBoxRun  # pylint: disable=cyclic-import
@@ -228,3 +201,18 @@ class Platform:
         self.check_sandbox_config = self._check_sandbox_config_buildboxrun
         self.create_sandbox = self._create_buildboxrun_sandbox
         return True
+
+    # Dummy sandbox methods
+    @staticmethod
+    def _check_dummy_sandbox_config(config):
+        pass
+
+    def _create_dummy_sandbox(self, *args, **kwargs):
+        dummy_reasons = " and ".join(self.dummy_reasons)
+        kwargs["dummy_reason"] = dummy_reasons
+        return SandboxDummy(*args, **kwargs)
+
+    def _setup_dummy_sandbox(self):
+        self.check_sandbox_config = Platform._check_dummy_sandbox_config
+        self.create_sandbox = self._create_dummy_sandbox
+        return True
diff --git a/src/buildstream/_platform/win32.py b/src/buildstream/_platform/win32.py
deleted file mode 100644
index 5045c9e3e..000000000
--- a/src/buildstream/_platform/win32.py
+++ /dev/null
@@ -1,35 +0,0 @@
-#
-#  Copyright (C) 2019 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/>.
-
-from ..sandbox import SandboxDummy
-
-from .platform import Platform
-
-
-class Win32(Platform):
-    @staticmethod
-    def _check_dummy_sandbox_config(config):
-        pass
-
-    @staticmethod
-    def _create_dummy_sandbox(*args, **kwargs):
-        kwargs["dummy_reason"] = "There are no supported sandbox technologies for Win32 at this time."
-        return SandboxDummy(*args, **kwargs)
-
-    def _setup_dummy_sandbox(self):
-        self.check_sandbox_config = Win32._check_dummy_sandbox_config
-        self.create_sandbox = Win32._create_dummy_sandbox
-        return True
diff --git a/src/buildstream/testing/_utils/site.py b/src/buildstream/testing/_utils/site.py
index 577896fe5..d8ace859b 100644
--- a/src/buildstream/testing/_utils/site.py
+++ b/src/buildstream/testing/_utils/site.py
@@ -54,7 +54,7 @@ casd_path = utils.get_host_tool("buildbox-casd")
 CASD_SEPARATE_USER = bool(os.stat(casd_path).st_mode & stat.S_ISUID)
 del casd_path
 
-IS_LINUX = os.getenv("BST_FORCE_BACKEND", sys.platform).startswith("linux")
+IS_LINUX = sys.platform.startswith("linux")
 IS_WINDOWS = os.name == "nt"
 
 MACHINE_ARCH = Platform.get_host_arch()
diff --git a/tox.ini b/tox.ini
index d43609d3e..bc64928a8 100644
--- a/tox.ini
+++ b/tox.ini
@@ -50,7 +50,6 @@ deps =
 passenv =
     ARTIFACT_CACHE_SERVICE
     BST_CAS_STAGING_ROOT
-    BST_FORCE_BACKEND
     BST_FORCE_START_METHOD
     GI_TYPELIB_PATH
     INTEGRATION_CACHE