Add support for no parent directory inference (#832) (#834)

Add feature as described in #832.

RELNOTES: Automatic creation of parent directory specifications for
paths with depth can be prevented in `pkg_tar` archives by setting `create_parents=False`.

5 files changed, 44 insertions, 15 deletions

diff --git a/docs/latest.md b/docs/latest.md
index eea6982..c0c9822 100755
--- a/docs/latest.md
+++ b/docs/latest.md
@@ -287,7 +287,7 @@ pkg_tar(<a href="#pkg_tar-name">name</a>, <a href="#pkg_tar-allow_duplicates_wit
              <a href="#pkg_tar-empty_dirs">empty_dirs</a>, <a href="#pkg_tar-empty_files">empty_files</a>, <a href="#pkg_tar-extension">extension</a>, <a href="#pkg_tar-files">files</a>, <a href="#pkg_tar-include_runfiles">include_runfiles</a>, <a href="#pkg_tar-mode">mode</a>, <a href="#pkg_tar-modes">modes</a>, <a href="#pkg_tar-mtime">mtime</a>, <a href="#pkg_tar-out">out</a>,
              <a href="#pkg_tar-owner">owner</a>, <a href="#pkg_tar-ownername">ownername</a>, <a href="#pkg_tar-ownernames">ownernames</a>, <a href="#pkg_tar-owners">owners</a>, <a href="#pkg_tar-package_dir">package_dir</a>, <a href="#pkg_tar-package_dir_file">package_dir_file</a>, <a href="#pkg_tar-package_file_name">package_file_name</a>,
              <a href="#pkg_tar-package_variables">package_variables</a>, <a href="#pkg_tar-portable_mtime">portable_mtime</a>, <a href="#pkg_tar-private_stamp_detect">private_stamp_detect</a>, <a href="#pkg_tar-remap_paths">remap_paths</a>, <a href="#pkg_tar-srcs">srcs</a>, <a href="#pkg_tar-stamp">stamp</a>,
-             <a href="#pkg_tar-strip_prefix">strip_prefix</a>, <a href="#pkg_tar-symlinks">symlinks</a>)
+             <a href="#pkg_tar-strip_prefix">strip_prefix</a>, <a href="#pkg_tar-symlinks">symlinks</a>, <a href="#pkg_tar-create_parents">symlinks</a>)
 </pre>
 
 
@@ -326,6 +326,7 @@ pkg_tar(<a href="#pkg_tar-name">name</a>, <a href="#pkg_tar-allow_duplicates_wit
 | <a id="pkg_tar-stamp"></a>stamp |  Enable file time stamping.  Possible values: <li>stamp = 1: Use the time of the build as the modification time of each file in the archive. <li>stamp = 0: Use an "epoch" time for the modification time of each file. This gives good build result caching. <li>stamp = -1: Control the chosen modification time using the --[no]stamp flag. <div class="since"><i>Since 0.5.0</i></div>   | Integer | optional | 0 |
 | <a id="pkg_tar-strip_prefix"></a>strip_prefix |  (note: Use strip_prefix = "." to strip path to the package but preserve relative paths of sub directories beneath the package.)   | String | optional | "" |
 | <a id="pkg_tar-symlinks"></a>symlinks |  -   | <a href="https://bazel.build/docs/skylark/lib/dict.html">Dictionary: String -> String</a> | optional | {} |
+| <a id="pkg_tar-create_parents"></a>create_parents |  Implicitly create parent directories with default permissions for file paths where parent directories are not specified. | Boolean | optional | True |
 
 
 
diff --git a/pkg/private/tar/build_tar.py b/pkg/private/tar/build_tar.py
index f4b9f0d..81ad03f 100644
--- a/pkg/private/tar/build_tar.py
+++ b/pkg/private/tar/build_tar.py
@@ -42,7 +42,7 @@ class TarFile(object):
   class DebError(Exception):
     pass
 
-  def __init__(self, output, directory, compression, compressor, default_mtime):
+  def __init__(self, output, directory, compression, compressor, create_parents, default_mtime):
     # Directory prefix on all output paths
     d = directory.strip('/')
     self.directory = (d + '/') if d else None
@@ -50,12 +50,14 @@ class TarFile(object):
     self.compression = compression
     self.compressor = compressor
     self.default_mtime = default_mtime
+    self.create_parents = create_parents
 
   def __enter__(self):
     self.tarfile = tar_writer.TarFileWriter(
         self.output,
         self.compression,
         self.compressor,
+        self.create_parents,
         default_mtime=self.default_mtime)
     return self
 
@@ -383,6 +385,10 @@ def main():
            'path/to/file=root.root.')
   parser.add_argument('--stamp_from', default='',
                       help='File to find BUILD_STAMP in')
+  parser.add_argument('--create_parents',
+                      action='store_true',
+                      help='Automatically creates parent directories implied by a'
+                           ' prefix if they do not exist')
   options = parser.parse_args()
 
   # Parse modes arguments
@@ -432,7 +438,8 @@ def main():
       directory = helpers.GetFlagValue(options.directory),
       compression = options.compression,
       compressor = options.compressor,
-      default_mtime=default_mtime) as output:
+      default_mtime=default_mtime,
+      create_parents=options.create_parents) as output:
 
     def file_attributes(filename):
       if filename.startswith('/'):
diff --git a/pkg/private/tar/tar.bzl b/pkg/private/tar/tar.bzl
index 963cb5a..8bea9fb 100644
--- a/pkg/private/tar/tar.bzl
+++ b/pkg/private/tar/tar.bzl
@@ -173,6 +173,9 @@ def _pkg_tar_impl(ctx):
     args.set_param_file_format("flag_per_line")
     args.use_param_file("@%s", use_always = False)
 
+    if ctx.attr.create_parents:
+        args.add("--create_parents")
+
     inputs = depset(
         direct = ctx.files.deps + files,
         transitive = mapping_context.file_deps,
@@ -264,6 +267,7 @@ pkg_tar_impl = rule(
         "compressor_args": attr.string(
             doc = """Arg list for `compressor`.""",
         ),
+        "create_parents": attr.bool(default = True),
 
         # Common attributes
         "out": attr.output(mandatory = True),
diff --git a/pkg/private/tar/tar_writer.py b/pkg/private/tar/tar_writer.py
index 325db76..957ce45 100644
--- a/pkg/private/tar/tar_writer.py
+++ b/pkg/private/tar/tar_writer.py
@@ -46,6 +46,7 @@ class TarFileWriter(object):
                name,
                compression='',
                compressor='',
+               create_parents=False,
                default_mtime=None,
                preserve_tar_mtimes=True):
     """TarFileWriter wraps tarfile.open().
@@ -106,6 +107,7 @@ class TarFileWriter(object):
     # we can adjust that here based on the setting of root_dirctory.
     self.directories.add('/')
     self.directories.add('./')
+    self.create_parents = create_parents
 
   def __enter__(self):
     return self
@@ -219,7 +221,8 @@ class TarFileWriter(object):
       mtime = self.default_mtime
 
     # Make directories up the file
-    self.add_parents(name, mtime=mtime, mode=0o755, uid=uid, gid=gid, uname=uname, gname=gname)
+    if self.create_parents:
+      self.add_parents(name, mtime=mtime, mode=0o755, uid=uid, gid=gid, uname=uname, gname=gname)
 
     tarinfo = tarfile.TarInfo(name)
     tarinfo.mtime = mtime
@@ -291,14 +294,15 @@ class TarFileWriter(object):
         if prefix:
           in_name = os.path.normpath(prefix + in_name).replace(os.path.sep, '/')
         tarinfo.name = in_name
-        self.add_parents(
-            path=tarinfo.name,
-            mtime=tarinfo.mtime,
-            mode=0o755,
-            uid=tarinfo.uid,
-            gid=tarinfo.gid,
-            uname=tarinfo.uname,
-            gname=tarinfo.gname)
+        if self.create_parents:
+          self.add_parents(
+              path=tarinfo.name,
+              mtime=tarinfo.mtime,
+              mode=0o755,
+              uid=tarinfo.uid,
+              gid=tarinfo.gid,
+              uname=tarinfo.uname,
+              gname=tarinfo.gname)
 
         if prefix is not None:
           # Relocate internal hardlinks as well to avoid breaking them.
diff --git a/tests/tar/tar_writer_test.py b/tests/tar/tar_writer_test.py
index ad31b0c..8503d31 100644
--- a/tests/tar/tar_writer_test.py
+++ b/tests/tar/tar_writer_test.py
@@ -138,7 +138,7 @@ class TarFileWriterTest(unittest.TestCase):
         {"name": "foo/a", "data": b"a"},
         {"name": "foo/ab", "data": b"ab"},
         ]
-    with tar_writer.TarFileWriter(self.tempfile) as f:
+    with tar_writer.TarFileWriter(self.tempfile, create_parents=True) as f:
       datafile = self.data_files.Rlocation(
           "rules_pkg/tests/testdata/tar_test.tar")
       f.add_tar(datafile, name_filter=lambda n: n != "./b", prefix="foo")
@@ -176,7 +176,7 @@ class TarFileWriterTest(unittest.TestCase):
         self.assertEqual(output_file.mtime, 0)
 
   def testAddingDirectoriesForFile(self):
-    with tar_writer.TarFileWriter(self.tempfile) as f:
+    with tar_writer.TarFileWriter(self.tempfile, create_parents=True) as f:
       f.add_file("d/f")
     content = [
         {"name": "d", "mode": 0o755},
@@ -185,7 +185,7 @@ class TarFileWriterTest(unittest.TestCase):
     self.assertTarFileContent(self.tempfile, content)
 
   def testAddingDirectoriesForFileManually(self):
-    with tar_writer.TarFileWriter(self.tempfile) as f:
+    with tar_writer.TarFileWriter(self.tempfile, create_parents=True) as f:
       f.add_file("d", tarfile.DIRTYPE)
       f.add_file("d/f")
 
@@ -210,6 +210,19 @@ class TarFileWriterTest(unittest.TestCase):
     ]
     self.assertTarFileContent(self.tempfile, content)
 
+  def testAddingOnlySpecifiedFiles(self):
+    with tar_writer.TarFileWriter(self.tempfile) as f:
+      f.add_file("a", tarfile.DIRTYPE)
+      f.add_file("a/b", tarfile.DIRTYPE)
+      f.add_file("a/b/", tarfile.DIRTYPE)
+      f.add_file("a/b/c/f")
+    content = [
+        {"name": "a", "mode": 0o755},
+        {"name": "a/b", "mode": 0o755},
+        {"name": "a/b/c/f"},
+    ]
+    self.assertTarFileContent(self.tempfile, content)
+
   def testPackageDirAttribute(self):
     """Tests package_dir of pkg_tar."""
     package_dir = self.data_files.Rlocation(