MappingException: Error mapping GraphModel to instance - neo4j

Question

I'm trying to follow the new Cineasts app with SDN 4.0.0.M1 and SpringBoot to learn Spring and Neo4j but I have an error when I try to access the movie url with
curl http://localhost:8080/movies
MappingException: Error mapping GraphModel to instance
I implemented the minimum to get something working so the code is simple but I probably forgot something
the movie class
#NodeEntity
public class Movie {
#GraphId
private Long nodeId;
private String id;
private String title;
public Movie() {
}
public Movie(String id, String title) {
this.id = id;
this.title = title;
}
}
the associated MovieRepository is empty at the moment
public interface MovieRepository extends GraphRepository<Movie> {
}
the MovieController
#Autowired
private MovieRepository movieRepository;
#Autowired
private Session session;
#RequestMapping(value = "/movies/{id}", method = RequestMethod.GET, headers = "Accept=application/json")
public
#ResponseBody
Movie getMovie(#PathVariable String id) {
return IteratorUtil.firstOrNull(findMovieByProperty("id", id));
}
public Iterable<Movie> findMovieByProperty(String propertyName, Object propertyValue) {
return session.loadByProperty(Movie.class, new Property(propertyName, propertyValue));
}
and the main class with database connection
#SpringBootApplication
#EnableNeo4jRepositories("cineasts.repository")
#EnableTransactionManagement
public class CineastsApplication extends Neo4jConfiguration {
public static final int NEO4J_PORT = 7474;
#Bean
public Neo4jServer neo4jServer() {
return new RemoteServer("http://localhost:" + NEO4J_PORT);
}
#Override
public SessionFactory getSessionFactory() {
return new SessionFactory("org.neo4j.cineasts.domain");
}
#Override
#Bean
#Scope(value = "session", proxyMode = ScopedProxyMode.TARGET_CLASS)
public Session getSession() throws Exception {
return super.getSession();
}
public static void main(String[] args) {
SpringApplication.run(CineastsApplication.class, args);
}
}
I started Neo4j and added one record with Neo4j browser
CREATE (m:Movie {id:1, name:'The Matrix'}) return m
when I go to localhost:8080 I can see the json response
{
"_links" : {
"movies" : {
"href" : "http://localhost:8080/movies"
},
"profile" : {
"href" : "http://localhost:8080/alps"
}
}
but it fails to display the movies or http://localhost:8080/movies/1 record I just created. Any idea to fix this or get a more relevant message?
Thanks!

Answer 1

The problem could be the fact that your entity definition does not match that of the node you've created.
The Movie class defines a property id of data type String, and a property title of type String.
The Cypher you used however
CREATE (m:Movie {id:1, name:'The Matrix'}) return m
creates a node with a number id instead of a String id and a name property instead of a title property.
Changing the above to
CREATE (m:Movie {id:'1', title:'The Matrix'}) return m
should fix it.