Support persistence of dynamically generated CGLib Beans [DATAMONGO-762]

[spring-projects-issues]

Sathish Kumar Thiyagarajan opened DATAMONGO-762 and commented

Steps:

1. Generate a Dynamic Bean Class using CGLib
   Name of the Bean: ProxyBean
   Name of the Property: properetyName

2. Create Instance of the ProxyBean.

3. Populate value for the "propertyName"

4. Save the record with MongoDB

Expected Result:
A new Record should get added with Collection Name as 'ProxyBean' and field name as 'propertyName'

Actual Result:
Getting an Exception as given below
Exception in thread "main" java.lang.IllegalArgumentException: fields stored in the db can't start with '$' (Bad Key: '$cglib_prop_propertyName')
at com.mongodb.DBCollection.validateKey(DBCollection.java:1450)
at com.mongodb.DBCollection._checkKeys(DBCollection.java:1410)
at com.mongodb.DBCollection._checkObject(DBCollection.java:1397)
at com.mongodb.DBCollection.save(DBCollection.java:800)
at com.mongodb.DBCollection.save(DBCollection.java:786)

Reference:

PAF Maven Project with main Class App.java

---

Affects: 1.2.3

Attachments:

• Spring-Mongo-CGLib.zip (3.65 kB)
• Spring-Mongo-CGLib-Patch.zip (16.33 kB)

[spring-projects-issues]

Sathish Kumar Thiyagarajan commented

Patch that solves this issue

[spring-projects-issues]

Sathish Kumar Thiyagarajan commented

Found a partial Fix for the problem.

1. Latest release from Spring release (Eg. 1.3.1.RELEASE) expose the method to set FieldNamingStrategy from MongoMappingContext. Below code will solve the issue for all fields except ID Property.

   ((MongoMappingContext) mongoOperation.getConverter().getMappingContext()).setFieldNamingStrategy(new FieldNamingStrategy() {
       @Override
       public String getFieldName(MongoPersistentProperty property) {
           return property.getName().replaceAll("\\$cglib_prop_", "");
       }
   });
   

2. For ID Property, Spring Mongo uses separete flow to find the approperiate Name. ( Through persistant Entity). So ID names has to be proper always. We can solve the issue my making CGLib Dynamic Beans extend a Java Class that has defined a proper ID Field with Annotation.

E.g:

public class BaseObject {

@Id
private String name;

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

}

PFA Spring-Mongo-CGLib-Patch.zip for the working patch

[spring-projects-issues]

Thomas Darimont commented

Hello Sathish,

thanks for the workaround - we're considering this as a new feature for the upcoming development iterations.

Cheers,
Thomas

[spring-projects-issues]

Christoph Strobl commented

Proxy resolution has been solved in the past few years. This works as designed on current master (3.0)