title: Proto 3: A way to add metadata at field level
body: <p>I am using protobuf-gradle-plugin to generate java class from the proto files.</p>
  
  <p>My proto file looks like </p>
  
  <pre><code>syntax = "proto3";
  
  package com.address;
  option java_package = "com.address";
  
  
  message AddressesMessage {
   int32 id = 1;
   string address_line_1 = 4;
   string address_line_2 = 5;
   string city = 7;
   string postal_code = 9;
   string country = 10;
  }
  </code></pre>
  
  <p>The plugin is generating classes for me but now I want to add some metadata information at field level. Like </p>
  
  <pre><code>syntax = "proto3";
  
  package com.address;
  option java_package = "com.address";
  
  
  message AddressesMessage {
   int32 id = 1 [ (meta) = { isfact: false }];
   string address_line_1 = 4;
   string address_line_2 = 5;
   string city = 7;
   string postal_code = 9;
   string country = 10;
  }
  </code></pre>
  
  <p>Is this possible?</p>