Implmented export_to_tar for casbaseddirectory

6 files changed, 79 insertions, 1 deletions

diff --git a/src/buildstream/storage/_casbaseddirectory.py b/src/buildstream/storage/_casbaseddirectory.py
index ea4862e50..7bd9ceea0 100644
--- a/src/buildstream/storage/_casbaseddirectory.py
+++ b/src/buildstream/storage/_casbaseddirectory.py
@@ -28,6 +28,9 @@ See also: :ref:`sandboxing`.
 """
 
 import os
+import stat
+import tarfile as tarfilelib
+from io import StringIO
 
 from .._protos.build.bazel.remote.execution.v2 import remote_execution_pb2
 from .directory import Directory, VirtualDirectoryError, _FileType
@@ -413,7 +416,33 @@ class CasBasedDirectory(Directory):
         self.cas_cache.checkout(to_directory, self._get_digest(), can_link=can_link)
 
     def export_to_tar(self, tarfile, destination_dir, mtime=BST_ARBITRARY_TIMESTAMP):
-        raise NotImplementedError()
+        for filename, entry in self.index.items():
+            arcname = os.path.join(destination_dir, filename)
+            if entry.type == _FileType.DIRECTORY:
+                tarinfo = tarfilelib.TarInfo(arcname)
+                tarinfo.mtime = mtime
+                tarinfo.type = tarfilelib.DIRTYPE
+                tarinfo.mode = 0o755
+                tarfile.addfile(tarinfo)
+                self.descend(filename).export_to_tar(tarfile, arcname, mtime)
+            elif entry.type == _FileType.REGULAR_FILE:
+                source_name = self.cas_cache.objpath(entry.digest)
+                tarinfo = tarfilelib.TarInfo(arcname)
+                tarinfo.mtime = mtime
+                tarinfo.mode |= entry.is_executable & stat.S_IXUSR
+                tarinfo.size = os.path.getsize(source_name)
+                with open(source_name, "rb") as f:
+                    tarfile.addfile(tarinfo, f)
+            elif entry.type == _FileType.SYMLINK:
+                tarinfo = tarfilelib.TarInfo(arcname)
+                tarinfo.mtime = mtime
+                tarinfo.mode |= entry.is_executable & stat.S_IXUSR
+                tarinfo.linkname = entry.target
+                tarinfo.type = tarfilelib.SYMTYPE
+                f = StringIO(entry.target)
+                tarfile.addfile(tarinfo, f)
+            else:
+                raise VirtualDirectoryError("can not export file type {} to tar".format(entry.type))
 
     def _mark_changed(self):
         """ It should not be possible to externally modify a CAS-based
diff --git a/tests/frontend/buildcheckout.py b/tests/frontend/buildcheckout.py
index a3f68c031..dd4a461ea 100644
--- a/tests/frontend/buildcheckout.py
+++ b/tests/frontend/buildcheckout.py
@@ -425,6 +425,49 @@ def test_build_checkout_tarball_is_deterministic(datafiles, cli):
 
 
 @pytest.mark.datafiles(DATA_DIR)
+def test_build_checkout_tarball_links(datafiles, cli):
+    project = str(datafiles)
+    checkout = os.path.join(cli.directory, 'checkout.tar')
+    extract = os.path.join(cli.directory, 'extract')
+
+    result = cli.run(project=project, args=['build', 'import-links.bst'])
+    result.assert_success()
+
+    builddir = os.path.join(cli.directory, 'build')
+    assert os.path.isdir(builddir)
+    assert not os.listdir(builddir)
+
+    checkout_args = ['artifact', 'checkout', '--tar', checkout, 'import-links.bst']
+
+    result = cli.run(project=project, args=checkout_args)
+    result.assert_success()
+
+    tar = tarfile.open(name=checkout, mode="r:")
+    tar.extractall(extract)
+    assert open(os.path.join(extract, 'basicfolder', 'basicsymlink')).read() == "file contents\n"
+
+
+@pytest.mark.datafiles(DATA_DIR)
+def test_build_checkout_links(datafiles, cli):
+    project = str(datafiles)
+    checkout = os.path.join(cli.directory, 'checkout')
+
+    result = cli.run(project=project, args=['build', 'import-links.bst'])
+    result.assert_success()
+
+    builddir = os.path.join(cli.directory, 'build')
+    assert os.path.isdir(builddir)
+    assert not os.listdir(builddir)
+
+    checkout_args = ['artifact', 'checkout', '--directory', checkout, 'import-links.bst']
+
+    result = cli.run(project=project, args=checkout_args)
+    result.assert_success()
+
+    assert open(os.path.join(checkout, 'basicfolder', 'basicsymlink')).read() == "file contents\n"
+
+
+@pytest.mark.datafiles(DATA_DIR)
 @pytest.mark.parametrize("hardlinks", [("copies"), ("hardlinks")])
 def test_build_checkout_nonempty(datafiles, cli, hardlinks):
     project = str(datafiles)
diff --git a/tests/frontend/project/elements/import-links.bst b/tests/frontend/project/elements/import-links.bst
new file mode 100644
index 000000000..42b279ee2
--- /dev/null
+++ b/tests/frontend/project/elements/import-links.bst
@@ -0,0 +1,4 @@
+kind: import
+sources:
+- kind: local
+  path: files/files-and-links
diff --git a/tests/frontend/project/files/files-and-links/basicfile b/tests/frontend/project/files/files-and-links/basicfile
new file mode 100644
index 000000000..d03e2425c
--- /dev/null
+++ b/tests/frontend/project/files/files-and-links/basicfile
@@ -0,0 +1 @@
+file contents
diff --git a/tests/frontend/project/files/files-and-links/basicfolder/basicsymlink b/tests/frontend/project/files/files-and-links/basicfolder/basicsymlink
new file mode 120000
index 000000000..e2b4f7423
--- /dev/null
+++ b/tests/frontend/project/files/files-and-links/basicfolder/basicsymlink
@@ -0,0 +1 @@
+../basicfile
\ No newline at end of file
diff --git a/tests/frontend/project/files/files-and-links/basicfolder/subdir-file b/tests/frontend/project/files/files-and-links/basicfolder/subdir-file
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/tests/frontend/project/files/files-and-links/basicfolder/subdir-file