OK, I got it. Many thanks for your support! /Fredrik
2018-01-10 2:11 GMT+01:00 Hugi Thordarson <h...@karlmenn.is>: > Hi Fredrik. > > Jackson is attempting to serialize an entire universe of java objects > accessible from DataObject (including everything returned by > getObjectContext() (and then everything that comes with that)) and > obviously it doesn't know how to turn these into JSON. > You could solve this by creating custom Jackson serializers for your > DataObject subclasses, but I'd sincerely recommend just creating separate > classes for modeling your web service return types. It's easy to do and > that way your JSON API design won't change with your DB design. > > Cheers, > - hugi > > > > On 9 Jan 2018, at 20:51, Fredrik Widengren <fredrik.wideng...@gmail.com> > wrote: > > > > Thanks for your help! > > > > Below you can see my controller which is basically the Spring Boot "Hello > > World" REST example, plus my Cayenne test. > > When I access http://localhost:8080/greeting, I get the JSON result > below: > > > > {"id":1,"content":"Hello, World!"} > > > > When I access http://localhost:8080/recipe/id=15, I'm directed to a > Spring > > Boot default error page. But in the log I can see that Cayenne works > fine, > > the object is fetched as it should. > > > > *// SPRING BOOT LOG* > > 2018-01-09 21:41:04.733 INFO 6128 --- [io-8080-exec-38] > > o.a.cayenne.log.CommonsJdbcEventLogger : Detected and installed > adapter: > > org.apache.cayenne.dba.mysql.MySQLAdapter > > 2018-01-09 21:41:04.734 INFO 6128 --- [io-8080-exec-38] > > o.a.cayenne.log.CommonsJdbcEventLogger : --- transaction started. > > 2018-01-09 21:41:04.930 INFO 6128 --- [io-8080-exec-38] > > o.a.cayenne.log.CommonsJdbcEventLogger : SELECT `t0`.`Comment`, > > `t0`.`ID`, `t0`.`ID_privileges`, `t0`.`Instruction`, `t0`.`Name`, > > `t0`.`No_of_servings`, `t0`.`Rating`, `t0`.`Source`, `t0`.`Timestamp`, > > `t0`.`Username` FROM `foodbase`.`recipes` `t0` WHERE `t0`.`ID` = ? [bind: > > 1->ID:13] > > 2018-01-09 21:41:05.338 INFO 6128 --- [io-8080-exec-38] > > o.a.cayenne.log.CommonsJdbcEventLogger : === returned 1 row. - took > 579 > > ms. > > 2018-01-09 21:41:05.339 INFO 6128 --- [io-8080-exec-38] > > o.a.cayenne.log.CommonsJdbcEventLogger : +++ transaction committed. > > 2018-01-09 21:41:05.642 WARN 6128 --- [io-8080-exec-38] > > .w.s.m.s.DefaultHandlerExceptionResolver : Failed to write HTTP message: > > org.springframework.http.converter.HttpMessageNotWritableException: > Could > > not write JSON: No serializer found for class > > org.apache.cayenne.tx.TransactionFilter and no properties discovered to > > create BeanSerializer (to avoid exception, disable > > SerializationFeature.FAIL_ON_EMPTY_BEANS); nested exception is > > com.fasterxml.jackson.databind.JsonMappingException: No serializer found > > for class org.apache.cayenne.tx.TransactionFilter and no properties > > discovered to create BeanSerializer (to avoid exception, disable > > SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: > > model.Recipes["objectContext"]->org.apache.cayenne.access. > DataContext["channel"]->org.apache.cayenne.access. > DataDomain["filters"]->java.util.Collections$UnmodifiableRandomAccessList[ > 0]) > > 2018-01-09 21:41:05.965 ERROR 6128 --- [io-8080-exec-38] > > o.a.c.c.C.[.[.[.[dispatcherServlet] : Servlet.service() for servlet > > dispatcherServlet threw exception > > > > > > I have tested also to disable SerializationFeature.FAIL_ON_EMPTY_BEANS, > as > > suggested in the exception, with no luck. > > > > *// Class GreetingController* > > package hello; > > > > import java.util.List; > > import java.util.concurrent.atomic.AtomicLong; > > > > import org.apache.cayenne.ObjectContext; > > import org.apache.cayenne.configuration.server.ServerRuntime; > > import org.apache.cayenne.configuration.server.ServerRuntimeBuilder; > > import org.apache.cayenne.query.ObjectSelect; > > import org.springframework.web.bind.annotation.RequestMapping; > > import org.springframework.web.bind.annotation.RequestParam; > > import org.springframework.web.bind.annotation.RestController; > > > > import model.Recipes; > > import model.auto._Recipes; > > > > @RestController > > public class GreetingController { > > > > // Cayenne context > > ServerRuntime cayenneRuntime = > > ServerRuntimeBuilder.builder().addConfig("cayenne-project.xml").build(); > > ObjectContext context = cayenneRuntime.newContext(); > > > > // Hello World example variables > > private static final String template = "Hello, %s!"; > > private final AtomicLong counter = new AtomicLong(); > > > > @RequestMapping("/greeting") > > public Greeting greeting(@RequestParam(value="name", > > defaultValue="World") String name) { > > return new Greeting(counter.incrementAndGet(), > > String.format(template, name)); > > } > > > > @RequestMapping("/recipe") > > public Recipes getRecipe(@RequestParam(value="id") int id) { > > > > List <Recipes> recipesList = > > ObjectSelect.query(Recipes.class).where(Recipes.ID.eq(new > > Long(id))).select(context); > > > > return recipesList.get(0); > > > > } > > } > > > > 2018-01-09 9:00 GMT+01:00 Andrus Adamchik <and...@objectstyle.org>: > > > >> To clarify, I realize you are using Spring, but Spring is many things. > So > >> maybe you can post here the relevant code (of a REST endpoint?), so > that we > >> can advise on serialization. > >> > >> Andrus > >> > >> > >>> On Jan 9, 2018, at 10:04 AM, Andrus Adamchik <and...@objectstyle.org> > >> wrote: > >>> > >>> What technology are you using to serialize your data to JSON? Do you > >> have a code example? > >>> > >>> Andrus > >>> > >>> > >>>> On Jan 9, 2018, at 9:24 AM, Fredrik Widengren < > >> fredrik.wideng...@gmail.com> wrote: > >>>> > >>>> Hello Frank > >>>> Thanks for your mail. > >>>> They automatically included when running Spring Boot as I understand. > >> Also the ”Hello World” example is running fine, and that one returns the > >> answer in JSON. > >>>> > >>>> /Fredrik > >>>> > >>>> Skickat från min iPhone > >>>> > >>>>> 8 jan. 2018 kl. 23:07 skrev Frank Herrmann <frank.herrmann@ > >> modernizingmedicine.com>: > >>>>> > >>>>> Do you have the Jackson libraries included in your project? They are > >>>>> normally needed for JSON serialization/deserialization. > >>>>> > >>>>> On Mon, Jan 8, 2018 at 4:52 PM, Fredrik Widengren < > >>>>> fredrik.wideng...@gmail.com> wrote: > >>>>> > >>>>>> Hello, > >>>>>> > >>>>>> I'm testing to setup Cayenne with Spring Boot. I have created a > simple > >>>>>> REST service. Spring is working fine with a Hello World example from > >>>>>> Spring.io. > >>>>>> > >>>>>> When I try to send back my cayenne objects that I have generated > from > >>>>>> the Cayenne modeller, I get an exception that it can’t find a JSON > >>>>>> serializer. > >>>>>> > >>>>>> Error: > >>>>>> Could not write JSON: No serializer found for class > >>>>>> org.apache.cayenne.tx.TransactionFilter > >>>>>> > >>>>>> I have read that a common reason for this is that the class that you > >>>>>> try to serialize does not have any public getters/setters. The > >>>>>> generated classes (in the auto package) from the modeller that > extends > >>>>>> CayenneDataObject do have these public getters/setters. The class is > >>>>>> however abstract, but I'm using the class created by the modeller > that > >>>>>> extends the abstract modeller class. > >>>>>> > >>>>>> Anyone that have any experience from Cayenne and Spring that have > some > >>>>>> input? > >>>>>> > >>>>>> Many thanks! > >>>>>> > >>>>>> /Fredrik > >>>>>> > >>>>> > >>>>> > >>>>> > >>>>> -- > >>>>> FRANK HERRMANN > >>>>> SENIOR SOFTWARE ENGINEER > >>>>> > >>>>> T: 561-880-2998 x1563 > >>>>> > >>>>> E: frank.herrm...@modmed.com > >>>>> > >>>>> > >>>>> > >>>>> [image: [ Modernizing Medicine ]] <https://www.modmed.com/> > >>>>> [image: [ Facebook ]] <https://www.facebook.com/modernizingmedicine> > >> [image: > >>>>> [ LinkedIn ]] <https://www.linkedin.com/ > company/modernizing-medicine/> > >> [image: > >>>>> [ YouTube ]] <https://www.youtube.com/user/modernizingmedicine> > >> [image: [ > >>>>> Twitter ]] <https://twitter.com/modmed> [image: [ Blog ]] > >>>>> <https://www.modmed.com/BlogBeyondEMR> [image: [ Instagram ]] > >>>>> <https://instagram.com/modernizing_medicine> > >>>>> > >>>>> [image: [ MOMENTUM 2017 ]] <https://www.eventproducers. > >> events/momentum2017/> > >>> > >> > >> > >
