fix: allow pb2 files to be included in the output of py_gapic_assembly_pkg (#1855)

Author: parthea

packages/gapic-generator/rules_python_gapic/py_gapic_pkg.bzl

@@ -17,12 +17,16 @@ load("@rules_gapic//:gapic_pkg.bzl", "construct_package_dir_paths")
 def _py_gapic_src_pkg_impl(ctx):
     srcjar_srcs = []
     dir_srcs = []
+    py_srcs = []
     for dep in ctx.attr.deps:
         for f in dep.files.to_list():
             if f.is_directory:
                 dir_srcs.append(f)
             elif f.extension in ("srcjar", "jar", "zip"):
                 srcjar_srcs.append(f)
+            # Exclude source files and files for external packages
+            elif f.extension in ("py") and not f.is_source and 'external' not in f.path:
+                py_srcs.append(f)
 
     paths = construct_package_dir_paths(ctx.attr.package_dir, ctx.outputs.pkg, ctx.label.name)
 
@@ -34,6 +38,9 @@ def _py_gapic_src_pkg_impl(ctx):
     for dir_src in {dir_srcs}; do
         cp -rT -L $dir_src {package_dir_path}
     done
+    for py_src in {py_srcs}; do
+        cp $py_src {package_dir_path}
+    done
     # Replace 555 (forced by Bazel) permissions with 644
     find {package_dir_path} -type f -exec chmod 644 {{}} \\;
     cd {package_dir_path}/..
@@ -44,14 +51,15 @@ def _py_gapic_src_pkg_impl(ctx):
     """.format(
         srcjar_srcs = " ".join(["'%s'" % f.path for f in srcjar_srcs]),
         dir_srcs = " ".join(["'%s'" % f.path for f in dir_srcs]),
+        py_srcs =  " ".join(["'%s'" % f.path for f in py_srcs]),
         package_dir_path = paths.package_dir_path,
         package_dir = paths.package_dir,
         pkg = ctx.outputs.pkg.path,
         package_dir_expr = paths.package_dir_expr,
     )
 
     ctx.actions.run_shell(
-        inputs = srcjar_srcs + dir_srcs,
+        inputs = srcjar_srcs + dir_srcs + py_srcs,
         command = script,
         outputs = [ctx.outputs.pkg],
     )