Add a resoure loader library to load bazel data dependencies

PiperOrigin-RevId: 292490959
Change-Id: I0d2c7ba7574ef793499c4bd715de6da241f0467b

tensorflow/core/platform/BUILD

@@ -85,6 +85,7 @@ exports_files(
         "mutex.h",
         "net.h",
         "numa.h",
+        "resource_loader.h",
         "snappy.h",
         "stacktrace_handler.h",
         "subprocess.h",
@@ -513,6 +514,13 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "resource_loader",
+    testonly = 1,
+    textual_hdrs = ["resource_loader.h"],
+    deps = tf_platform_deps("resource_loader"),
+)
+
 cc_library(
     name = "rocm_rocdl_path",
     textual_hdrs = ["rocm_rocdl_path.h"],
@@ -907,6 +915,22 @@ tf_cc_test(
     ],
 )
 
+tf_cc_test(
+    name = "resource_loader_test",
+    size = "small",
+    srcs = ["resource_loader_test.cc"],
+    data = [
+        ":resource_loader.h",
+    ],
+    deps = [
+        ":resource_loader",
+        ":status",
+        "//tensorflow/core:lib",
+        "//tensorflow/core:test",
+        "//tensorflow/core:test_main",
+    ],
+)
+
 tf_cc_test(
     name = "ctstring_test",
     size = "small",

tensorflow/core/platform/default/BUILD

@@ -299,6 +299,22 @@ cc_library(
     }),
 )
 
+cc_library(
+    name = "resource_loader",
+    testonly = 1,
+    srcs = ["resource_loader.cc"],
+    hdrs = ["//tensorflow/core/platform:resource_loader.h"],
+    tags = [
+        "manual",
+        "no_oss",
+        "nobuilder",
+    ],
+    deps = [
+        "//tensorflow/core/platform:logging",
+        "@bazel_tools//tools/cpp/runfiles",
+    ],
+)
+
 cc_library(
     name = "rocm_rocdl_path",
     srcs = ["rocm_rocdl_path.cc"],

tensorflow/core/platform/default/resource_loader.cc

@@ -0,0 +1,37 @@
+/* Copyright 2020 The TensorFlow 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.
+==============================================================================*/
+
+#include "tensorflow/core/platform/resource_loader.h"
+
+#include "tensorflow/core/platform/logging.h"
+#include "tools/cpp/runfiles/runfiles.h"
+
+using bazel::tools::cpp::runfiles::Runfiles;
+
+namespace tensorflow {
+
+std::string GetDataDependencyFilepath(const std::string& relative_path) {
+  std::string error;
+  std::unique_ptr<Runfiles> runfiles(Runfiles::CreateForTest(&error));
+
+  if (runfiles == nullptr) {
+    LOG(FATAL) << "Unable to access the data dependencies of this test.\n"
+                  "Make sure you are running this test using bazel.";
+  }
+  string root_dir = "org_tensorflow/";
+  return runfiles->Rlocation(root_dir + relative_path);
+}
+
+}  // namespace tensorflow

tensorflow/core/platform/resource_loader.h

@@ -0,0 +1,32 @@
+/* Copyright 2020 The TensorFlow 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.
+==============================================================================*/
+
+// Small helper library to access "data" dependencies defined in BUILD files.
+// Requires the relative paths starting from tensorflow/...
+// For example, to get this file, a user would call:
+// GetDataDependencyFilepath("tensorflow/core/platform/resource_loadder.h")
+
+#ifndef TENSORFLOW_CORE_PLATFORM_RESOURCE_LOADER_H_
+#define TENSORFLOW_CORE_PLATFORM_RESOURCE_LOADER_H_
+
+#include <string>
+
+namespace tensorflow {
+
+std::string GetDataDependencyFilepath(const std::string& relative_path);
+
+}  // namespace tensorflow
+
+#endif  // TENSORFLOW_CORE_PLATFORM_RESOURCE_LOADER_H_

tensorflow/core/platform/resource_loader_test.cc

@@ -0,0 +1,33 @@
+/* Copyright 2020 The TensorFlow 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.
+==============================================================================*/
+
+#include "tensorflow/core/platform/resource_loader.h"
+
+#include "tensorflow/core/platform/env.h"
+#include "tensorflow/core/platform/logging.h"
+#include "tensorflow/core/platform/status.h"
+#include "tensorflow/core/platform/test.h"
+
+namespace tensorflow {
+
+const char kDataDependencyPath[] = "tensorflow/core/platform/resource_loader.h";
+
+TEST(ResourceLoaderTest, FindsAndOpensFile) {
+  string filepath = GetDataDependencyFilepath(kDataDependencyPath);
+  Status s = Env::Default()->FileExists(filepath);
+  EXPECT_TRUE(s.ok()) << "No file found at this location: " << filepath;
+}
+
+}  // namespace tensorflow