1) Do not use gflags in the example binary code.

2) Also surface wv_cas_key_fetcher_example to partner.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=229965302

example/wv_cas_ecm_example.cc

@@ -13,17 +13,15 @@
 #include <iostream>
 #include <string>
 
-#include "gflags/gflags.h"
 #include "media_cas_packager_sdk/public/wv_cas_ecm.h"
 #include "media_cas_packager_sdk/public/wv_cas_types.h"
 
-DEFINE_int32(content_iv_size, 8, "Content IV size");
-DEFINE_bool(key_rotation, true, "Whether key rotation is enabled");
-DEFINE_string(crypto_mode, "CSA2", "Only CBC, CTR, or CSA2 is allowed");
-DEFINE_int32(ecm_pid, 149, "PID for the ECM packet");
-DEFINE_string(output_file, "",
-              "If specified, generated ECM TS packet will be written to the "
-              "specified output file path");
+const size_t kContentIvSize = 8;
+const bool kKeyRotation = false;   // whether key rotation is enabled
+const char kCryptoMode[] = "CTR";  // CBC, CTR, or CSA2
+const int kEcmPid = 149;           // PID for the ECM packet
+const char kOutputFile[] =
+    "/tmp/ecm.ts";  // ECM TS packet will be output to here
 
 const char kCsaEvenKey[] = "even_key";                    // 8 bytes
 const char kEvenContentIv8Bytes[] = "even_iv.";           // 8 bytes
@@ -35,31 +33,31 @@ const char kOddContentIv8Bytes[] = "odd_iv..";           // 8 bytes
 const char kOddEntitlementKeyId[] = "fake_key_id2....";  // 16 bytes
 const char kOddEntitlementKey[] =
     "fakefakefakefakefakefakefake2...";  // 32 bytes
+const uint8_t kTableId = 0x80;
 const size_t kTsPacketSize = 188;
 
-widevine::cas::CryptoMode GetCryptoMode() {
-  if (FLAGS_crypto_mode.compare("CBC") == 0) {
+widevine::cas::CryptoMode GetCryptoMode(const std::string& crypto_mode) {
+  if (crypto_mode.compare("CBC") == 0) {
     return widevine::cas::CryptoMode::kAesCbc;
   }
-  if (FLAGS_crypto_mode.compare("CTR") == 0) {
+  if (crypto_mode.compare("CTR") == 0) {
     return widevine::cas::CryptoMode::kAesCtr;
   }
   return widevine::cas::CryptoMode::kDvbCsa2;
 }
 
-int main(int argc, char **argv) {
-  gflags::ParseCommandLineFlags(&argc, &argv, true);
+int main(int argc, char** argv) {
   // Generate ECM.
   widevine::cas::WvCasEcm wv_cas_ecm;
   widevine::cas::WvCasStatus status = wv_cas_ecm.Initialize(
-      FLAGS_content_iv_size, FLAGS_key_rotation, GetCryptoMode());
+      kContentIvSize, kKeyRotation, GetCryptoMode(kCryptoMode));
   if (status != widevine::cas::OK) {
     std::cerr << "Failed to initialize WV CAS ECM, error: "
               << widevine::cas::GetWvCasStatusMessage(status)
               << std::endl;
   }
   std::string ecm;
-  if (FLAGS_key_rotation) {
+  if (kKeyRotation) {
     status = wv_cas_ecm.GenerateEcm(
         kCsaEvenKey, kEvenContentIv8Bytes, kEvenEntitlementKeyId,
         kEvenEntitlementKey, kCsaOddKey, kOddContentIv8Bytes,
@@ -85,8 +83,7 @@ int main(int argc, char **argv) {
   // Generate ECM TS Packet.
   uint8_t packet[kTsPacketSize];
   uint8_t continuity_counter;  // not used.
-  status = wv_cas_ecm.GenerateTsPacket(ecm, FLAGS_ecm_pid,
-                                       /* table_id= */ 0x80,
+  status = wv_cas_ecm.GenerateTsPacket(ecm, kEcmPid, kTableId,
                                        &continuity_counter, packet);
   if (status != widevine::cas::OK) {
     std::cerr << "Failed to create ECM TS packet" << std::endl;
@@ -99,13 +96,11 @@ int main(int argc, char **argv) {
     std::cout << std::endl;
   }
   // Write ECM TS Packet to a file.
-  if (!FLAGS_output_file.empty()) {
     std::ofstream file;
-    file.open(FLAGS_output_file.c_str(), std::ios_base::binary);
+    file.open(kOutputFile, std::ios_base::binary);
     assert(file.is_open());
     file.write(reinterpret_cast<char *>(packet), kTsPacketSize);
     file.close();
-  }
 
   return 0;
 }

example/wv_cas_key_fetcher_example.cc

@@ -0,0 +1,68 @@
+////////////////////////////////////////////////////////////////////////////////
+// Copyright 2018 Google LLC.
+//
+// This software is licensed under the terms defined in the Widevine Master
+// License Agreement. For a copy of this agreement, please contact
+// widevine-licensing@google.com.
+////////////////////////////////////////////////////////////////////////////////
+
+
+#include <iostream>
+#include <string>
+
+#include "gflags/gflags.h"
+#include "glog/logging.h"
+#include "common/status.h"
+#include "media_cas_packager_sdk/public/wv_cas_key_fetcher.h"
+#include "protos/public/media_cas_encryption.pb.h"
+
+DEFINE_string(content_id, "21140844", "Content ID");
+DEFINE_bool(key_rotation, true, "Whether key rotation is enabled");
+DEFINE_string(track_type, "SD", "Provider name");
+
+int main(int argc, char **argv) {
+  gflags::ParseCommandLineFlags(&argc, &argv, true);
+  CHECK(!FLAGS_content_id.empty() && !FLAGS_track_type.empty())
+      << "Flags 'content_id' and 'track_type' are required";
+  // Required flags in key fetcher.
+  CHECK(!FLAGS_license_server.empty() && !FLAGS_signing_provider.empty() &&
+        !FLAGS_signing_key.empty() && !FLAGS_signing_iv.empty())
+      << "Flags 'license_server', 'signing_provider', 'signing_key' "
+         "and 'signing_iv' are required";
+
+  std::string request_str;
+  widevine::CasEncryptionRequest request;
+  request.set_provider(FLAGS_signing_provider);
+  request.set_content_id(FLAGS_content_id);
+  request.set_key_rotation(FLAGS_key_rotation);
+  // Only 1 track in this example.
+  request.add_track_types(FLAGS_track_type);
+  LOG(INFO) << "Request: " << request.ShortDebugString();
+  if (!request.SerializeToString(&request_str)) {
+    LOG(ERROR) << "Failed to serialize request";
+    return -1;
+  }
+
+  std::string signed_response_str;
+  widevine::cas::WvCasKeyFetcher key_fetcher;
+  widevine::Status status =
+      key_fetcher.RequestEntitlementKey(request_str, &signed_response_str);
+  if (!status.ok()) {
+    LOG(ERROR) << "Failed to request entitlement key";
+    return -1;
+  }
+  widevine::SignedCasEncryptionResponse signed_response;
+  if (!signed_response.ParseFromString(signed_response_str)) {
+    LOG(ERROR) << "Failed to deserialize signed response";
+    return -1;
+  }
+  LOG(INFO) << "Signed response: " << signed_response.ShortDebugString();
+  widevine::CasEncryptionResponse response;
+  if (!response.ParseFromString(signed_response.response())) {
+    LOG(ERROR) << "Failed to deserialize response";
+    return -1;
+  }
+  LOG(INFO) << "Response: " << response.ShortDebugString();
+
+  return 0;
+}

example/wv_cas_types_example.cc

@@ -10,13 +10,9 @@
 
 #include <string>
 
-#include "gflags/gflags.h"
 #include "glog/logging.h"
 #include "media_cas_packager_sdk/public/wv_cas_types.h"
 
-DEFINE_string(function_to_call, "CreateWvCasEncryptionRequestJson",
-              "Function in wv_cas_types to exercise");
-
 void CallCreateWvCasEncryptionRequestJson() {
   widevine::cas::WvCasEncryptionRequest request;
   request.content_id = "cont_id cont_id ";
@@ -25,13 +21,10 @@ void CallCreateWvCasEncryptionRequestJson() {
   request.key_rotation = true;
   std::string request_json;
   widevine::cas::CreateWvCasEncryptionRequestJson(request, &request_json);
-  LOG(INFO) << FLAGS_function_to_call << " returns " << request_json;
+  LOG(INFO) << "CreateWvCasEncryptionRequestJson returns " << request_json;
 }
 
 int main(int argc, char **argv) {
-  gflags::ParseCommandLineFlags(&argc, &argv, true);
-  if (FLAGS_function_to_call.compare("CreateWvCasEncryptionRequestJson") == 0) {
     CallCreateWvCasEncryptionRequestJson();
-  }
   return 0;
 }