How to generate binary files containing Protobuf serialization from human readable input (Applied to RealtimeBidding)

bidRequest.ad

DEPRECATED_protocol_version: 1
id: "\006\013\230\033\240b\242\310\204\252v\306\354S\0340"
ip: "0\217O"
user_agent: "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0;)"
country: "CA"
region: "CA-ON"
city: "Toronto"
url: "http://www.nytimes.com/pages/technology/index.html"
detected_language: "en"
detected_vertical {
  id: 608
  weight: 0.641945431083
}
detected_vertical {
  id: 24
  weight: 0.615661596479
}
detected_vertical {
  id: 474
  weight: 0.421220140846
}
detected_vertical {
  id: 379
  weight: 0.494118810167
}
detected_vertical {
  id: 23
  weight: 0.196397066403
}
adslot {
  id: 42
  width: 180
  height: 60
  excluded_attribute: 1
  excluded_attribute: 3
  allowed_vendor_type: 145
  allowed_vendor_type: 226
  allowed_vendor_type: 316
  allowed_vendor_type: 234
  allowed_vendor_type: 231
  matching_ad_data {
    adgroup_id: 49162214
  }
  matching_ad_data {
    adgroup_id: 38217668
  }
  publisher_settings_list_id: "$&O\270hO\005j\333\207!~DJ\277\371\217$\r_"
}
adslot {
  id: 91
  width: 728
  height: 90
  excluded_attribute: 1
  excluded_attribute: 9
  excluded_attribute: 7
  allowed_vendor_type: 227
  allowed_vendor_type: 198
  allowed_vendor_type: 238
  allowed_vendor_type: 143
  allowed_vendor_type: 312
  allowed_vendor_type: 316
  matching_ad_data {
    adgroup_id: 89764029
  }
  publisher_settings_list_id: "\273w&Q\346\306\001=2\271\001\263\364d\375\216`\267\365X"
}
is_test: true
cookie_version: 1
google_user_id: "bR-Rl03r_iQeeeioQSqQS_gA75U"
seller_network: "New York Times"
publisher_settings_list_id: "~\024^F8\t\352^|(\362\335\361\003I\237\224,\236\243"
cookie_age_seconds: 2542923
postal_code_prefix: "M4C"

ProtocolBufferFileGenerator.java

import com.google.adex.rtb.RealtimeBidding;
import com.google.protobuf.TextFormat;

import java.io.*;

public class ProtocolBufferFileGenerator {

    public void generateBinaryFile() throws IOException {
        RealtimeBidding.BidRequest.Builder builder = RealtimeBidding.BidRequest.newBuilder();

        TextFormat.merge(new InputStreamReader(getClass().getResourceAsStream("/bidRequest.ad")), builder);

        OutputStream output = new FileOutputStream(new File(System.getProperty("user.home"), "protobuf.bin"));
        output.write(builder.build().toByteArray());
        output.close();
    }
}