Modularize manifest python code

pkg/private/BUILD

@@ -91,6 +91,7 @@ py_binary(
         ":archive",
         ":build_info",
         ":helpers",
+        ":manifest",
     ],
 )
 
@@ -116,3 +117,10 @@ py_binary(
         ":helpers",
     ],
 )
+
+py_library(
+    name = "manifest",
+    srcs = ["manifest.py"],
+    srcs_version = "PY3",
+    visibility = ["//visibility:public"],
+)

pkg/private/build_tar.py

@@ -22,12 +22,7 @@
 import archive
 import helpers
 import build_info
-
-# These must be kept in sync with the values from private/pkg_files.bzl
-ENTRY_IS_FILE = 0  # Entry is a file: take content from <src>
-ENTRY_IS_LINK = 1  # Entry is a symlink: dest -> <src>
-ENTRY_IS_DIR = 2  # Entry is an empty dir
-ENTRY_IS_TREE = 3  # Entry is a tree artifact: take tree from <src>
+import manifest
 
 
 class TarFile(object):
@@ -262,32 +257,32 @@ def add_tree(self, tree_top, destpath, mode=None, ids=None, names=None):
             uname=names[0],
             gname=names[1])
 
-  def add_manifest_entry(self, entry, file_attributes):
-    entry_type, dest, src, mode, user, group = entry
+  def add_manifest_entry(self, entry_list, file_attributes):
+    entry = manifest.ManifestEntry(*entry_list)
 
     # Use the pkg_tar mode/owner remaping as a fallback
-    non_abs_path = dest.strip('/')
+    non_abs_path = entry.dest.strip('/')
     if file_attributes:
       attrs = file_attributes(non_abs_path)
     else:
       attrs = {}
     # But any attributes from the manifest have higher precedence
-    if mode is not None and mode != '':
-      attrs['mode'] = int(mode, 8)
-    if user:
-      if group:
-        attrs['names'] = (user, group)
+    if entry.mode is not None and entry.mode != '':
+      attrs['mode'] = int(entry.mode, 8)
+    if entry.user:
+      if entry.group:
+        attrs['names'] = (entry.user, entry.group)
       else:
         # Use group that legacy tar process would assign
-        attrs['names'] = (user, attrs.get('names')[1])
-    if entry_type == ENTRY_IS_LINK:
-      self.add_link(dest, src)
-    elif entry_type == ENTRY_IS_DIR:
-      self.add_empty_dir(dest, **attrs)
-    elif entry_type == ENTRY_IS_TREE:
-      self.add_tree(src, dest, **attrs)
+        attrs['names'] = (entry.user, attrs.get('names')[1])
+    if entry.entry_type == manifest.ENTRY_IS_LINK:
+      self.add_link(entry.dest, entry.src)
+    elif entry.entry_type == manifest.ENTRY_IS_DIR:
+      self.add_empty_dir(entry.dest, **attrs)
+    elif entry.entry_type == manifest.ENTRY_IS_TREE:
+      self.add_tree(entry.src, entry.dest, **attrs)
     else:
-      self.add_file(src, dest, **attrs)
+      self.add_file(entry.src, entry.dest, **attrs)
 
 
 def main():

pkg/private/manifest.py

@@ -0,0 +1,41 @@
+# Copyright 2021 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Common package builder manfiest helpers
+"""
+
+import collections
+
+# These must be kept in sync with the declarations in private/pkg_files.bzl
+ENTRY_IS_FILE = 0  # Entry is a file: take content from <src>
+ENTRY_IS_LINK = 1  # Entry is a symlink: dest -> <src>
+ENTRY_IS_DIR = 2  # Entry is an owned dir, possibly empty
+ENTRY_IS_TREE = 3  # Entry is a tree artifact: take tree from <src>
+
+ManifestEntry = collections.namedtuple("ManifestEntry",
+                                       ['entry_type', 'dest', 'src', 'mode', 'user', 'group'])
+
+
+def entry_type_to_string(et):
+    """Entry type stringifier"""
+    if et == ENTRY_IS_FILE:
+        return "file"
+    elif et == ENTRY_IS_LINK:
+        return "symlink",
+    elif et == ENTRY_IS_DIR:
+        return "directory"
+    elif et == ENTRY_IS_TREE:
+        return "tree"
+    else:
+        raise ValueError("Invalid entry id {}".format(et))

pkg/private/pkg_files.bzl

@@ -42,7 +42,7 @@ load(
 )
 
 # Possible values for entry_type
-# These must be kept in sync with the declarations in private/build_*.py
+# These must be kept in sync with the declarations in private/manifest.py.
 ENTRY_IS_FILE = 0  # Entry is a file: take content from <src>
 ENTRY_IS_LINK = 1  # Entry is a symlink: dest -> <src>
 ENTRY_IS_DIR = 2  # Entry is an empty dir