Fix S4004: Rule should not raise a violation when [DataMember] is applied

[cmenzi]

Description

I like this rule very much, because it's forcing good encapsulation. But when using [DataContract]s for DTOs, it's hard to fulfill this rule.

Repro steps

[DataContract]
public class Message
{
    [DataMember]
    [Required]
    public string Id { get; set; }

    [DataMember]
    [Required]
    public string MessageBody { get; set; }

    [DataMember]
    [Required]
    public Dictionary<string, string> Properties { get; set; }
}

Expected behavior

The rule should not raise, when [DataContract] attribute is attached to the class or maybe more explicitly [DataMember] is on the property.

Actual behavior

The rule raises a violation.

Known workarounds

• Implement custom serialization/deserialization for the class.
• Use custom backing fields and attach to attribute to datamember

Related information

• SonarC# 6.5.0.27846
• Visual Studio 2017.3
• MSBuild 15.3.409.57025