Say in my application, some users give us their last name, and others do not. In a REST API response, which body is preferred:With a null value:{firstName: Bob, lastName: null}Or just a missing key:{firstName: Bob}
null vs missing key in REST API Response
rest;api design;json
Consider removing empty or null values.If a property is optional or has an empty or null value, consider dropping the property from the JSON, unless there's a strong semantic reason for its existence.{  volume: 10,  // Even though the balance property's value is zero, it should be left in,  // since 0 signifies even balance (the value could be -1 for left  // balance and +1 for right balance.  balance: 0,  // The currentlyPlaying property can be left out since it is null.  // currentlyPlaying: null}Further ReadingGoogle Style Guide - Empty or Null Property ValuesShould null values be included in JSON responses from a REST API?