linear_solver: Add model_exporter_main.cc

ortools/linear_solver/CMakeLists.txt

@@ -15,6 +15,7 @@ file(GLOB _SRCS "*.h" "*.cc")
 list(REMOVE_ITEM _SRCS
   ${CMAKE_CURRENT_SOURCE_DIR}/solve.cc
 )
+list(FILTER _SRCS EXCLUDE REGEX "/model_exporter_main\\.cc")
 if(USE_SCIP)
   list(APPEND _SRCS ${LPI_GLOP_SRC})
 endif()

ortools/linear_solver/model_exporter_main.cc

@@ -0,0 +1,80 @@
+// Copyright 2010-2022 Google LLC
+// 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.
+
+// See kUsageStr below, and ./model_exporter.h.
+
+#include <cstdio>
+#include <string>
+
+#include "absl/strings/match.h"
+#include "google/protobuf/descriptor.h"
+#include "google/protobuf/io/zero_copy_stream_impl_lite.h"
+#include "google/protobuf/message.h"
+#include "google/protobuf/text_format.h"
+#include "ortools/base/commandlineflags.h"
+#include "ortools/base/file.h"
+#include "ortools/base/helpers.h"
+#include "ortools/base/init_google.h"
+#include "ortools/linear_solver/linear_solver.pb.h"
+#include "ortools/linear_solver/model_exporter.h"
+#include "ortools/util/file_util.h"
+
+ABSL_FLAG(std::string, input, "", "REQUIRED: Input file name");
+ABSL_FLAG(std::string, output, "", "REQUIRED: Output file name");
+ABSL_FLAG(bool, input_is_mp_model_request, false,
+          "Whether the input is a MPModelRequest proto.");
+ABSL_FLAG(bool, obfuscate, false,
+          "Whether variable and constaint names should be obfuscated.");
+
+static const char kUsageStr[] =
+    "Convert an operations_research::MPModelProto or"
+    " operations_research::MPModelRequest file (containing a single"
+    " proto, in ascii or wire format, possibly gzipped)"
+    " into a .lp or .mps file.";
+
+int main(int argc, char** argv) {
+  InitGoogle(kUsageStr, &argc, &argv, /*remove_flags=*/true);
+  std::string input_ascii_pb;
+  CHECK(!absl::GetFlag(FLAGS_input).empty() &&
+        !absl::GetFlag(FLAGS_output).empty())
+      << "--input and --output are required.";
+  operations_research::MPModelProto model_proto;
+  if (absl::GetFlag(FLAGS_input_is_mp_model_request)) {
+    operations_research::MPModelRequest request_proto;
+    CHECK(operations_research::ReadFileToProto(absl::GetFlag(FLAGS_input),
+                                               &request_proto));
+    model_proto.Swap(request_proto.mutable_model());
+  } else {
+    CHECK(operations_research::ReadFileToProto(absl::GetFlag(FLAGS_input),
+                                               &model_proto));
+  }
+  std::string output_contents;
+  operations_research::MPModelExportOptions options;
+  options.obfuscate = absl::GetFlag(FLAGS_obfuscate);
+  if (absl::EndsWith(absl::GetFlag(FLAGS_output), ".lp")) {
+    output_contents = ExportModelAsLpFormat(model_proto, options).value();
+  } else if (absl::EndsWith(absl::GetFlag(FLAGS_output), ".mps")) {
+    output_contents = ExportModelAsMpsFormat(model_proto, options).value();
+  } else if (absl::EndsWith(absl::GetFlag(FLAGS_output), ".pb.txt")) {
+    google::protobuf::io::StringOutputStream stream(&output_contents);
+    CHECK(google::protobuf::TextFormat::PrintToString(model_proto,
+                                                      &output_contents));
+  } else {
+    LOG(FATAL) << "Unsupported extension: " << absl::GetFlag(FLAGS_output)
+               << " (try: .lp, .mps or .pb.txt)";
+  }
+  CHECK_OK(file::SetContents(absl::GetFlag(FLAGS_output), output_contents,
+                             file::Defaults()));
+  fprintf(stderr, "Wrote '%s' successfully\n",
+          absl::GetFlag(FLAGS_output).c_str());
+}