Merge branch 'aevri/mtime1' into 'master'

storage.Directory.export_to_tar: default mtime=utils._magic_timestamp

Closes #914

See merge request !1149

buildstream/storage/_casbaseddirectory.py

@@ -36,7 +36,7 @@ from .._protos.build.bazel.remote.execution.v2 import remote_execution_pb2
 from .._exceptions import BstError
 from .directory import Directory, VirtualDirectoryError
 from ._filebaseddirectory import FileBasedDirectory
-from ..utils import FileListResult, safe_copy, list_relative_paths
+from ..utils import FileListResult, safe_copy, list_relative_paths, _magic_timestamp
 
 
 class IndexEntry():
@@ -535,7 +535,7 @@ class CasBasedDirectory(Directory):
                                 " The original error was: {}").
                                format(src_name, entry.target, e))
 
-    def export_to_tar(self, tarfile, destination_dir, mtime=0):
+    def export_to_tar(self, tarfile, destination_dir, mtime=_magic_timestamp):
         raise NotImplementedError()
 
     def mark_changed(self):

buildstream/storage/_filebaseddirectory.py

@@ -157,7 +157,7 @@ class FileBasedDirectory(Directory):
     # First, it sorts the results of os.listdir() to ensure the ordering of
     # the files in the archive is the same.  Second, it sets a fixed
     # timestamp for each entry. See also https://bugs.python.org/issue24465.
-    def export_to_tar(self, tf, dir_arcname, mtime=0):
+    def export_to_tar(self, tf, dir_arcname, mtime=_magic_timestamp):
         # We need directories here, including non-empty ones,
         # so list_relative_paths is not used.
         for filename in sorted(os.listdir(self.external_directory)):

buildstream/storage/directory.py

@@ -32,6 +32,7 @@ See also: :ref:`sandboxing`.
 """
 
 from .._exceptions import BstError, ErrorDomain
+from ..utils import _magic_timestamp
 
 
 class VirtualDirectoryError(BstError):
@@ -114,7 +115,7 @@ class Directory():
 
         raise NotImplementedError()
 
-    def export_to_tar(self, tarfile, destination_dir, mtime=0):
+    def export_to_tar(self, tarfile, destination_dir, mtime=_magic_timestamp):
         """ Exports this directory into the given tar file.
 
         Args:

tests/frontend/buildcheckout.py

@@ -252,6 +252,26 @@ def test_build_checkout_tarball_stdout(datafiles, cli):
     assert os.path.join('.', 'usr', 'include', 'pony.h') in tar.getnames()
 
 
+@pytest.mark.datafiles(DATA_DIR)
+def test_build_checkout_tarball_mtime_nonzero(datafiles, cli):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+    tarpath = os.path.join(cli.directory, 'mtime_tar.tar')
+
+    result = cli.run(project=project, args=['build', 'target.bst'])
+    result.assert_success()
+
+    checkout_args = ['artifact', 'checkout', '--tar', tarpath, 'target.bst']
+    result = cli.run(project=project, args=checkout_args)
+    result.assert_success()
+
+    tar = tarfile.TarFile(tarpath)
+    for tarinfo in tar.getmembers():
+        # An mtime of zero can be confusing to other software,
+        # e.g. ninja build and template toolkit have both taken zero mtime to
+        # mean 'file does not exist'.
+        assert tarinfo.mtime > 0
+
+
 @pytest.mark.datafiles(DATA_DIR)
 def test_build_checkout_tarball_is_deterministic(datafiles, cli):
     project = os.path.join(datafiles.dirname, datafiles.basename)