Create Document in CouchDB 2.0 fauxton using Java

Question

I created a default GWT project and trying to create a document in the database with a simple entry using CouchDB as my database. Previously we were using CouchDB 1.6 i.e futon as UI. Now, recently trying to use CouchDB 2.0 i.e Fauxton as UI.

PROBLEM:-

Unable to create a document in CouchDB 2.0.

SERVER SIDE CODE:-

public String greetServer(String input) throws IllegalArgumentException {
        // Verify that the input is valid. 
        System.out.println(input);

        Session session=new Session("192.168.1.48",5984);
        Database db=session.getDatabase("testing");
        Document doc=new Document();
        doc.put("name", input);
        db.saveDocument(doc);

        return "Hello, " + input;
    }

EXCEPTION:-

2017-02-22 17:23:41.147:WARN:/:qtp10750155-45: Exception while dispatching incoming RPC call
com.google.gwt.user.server.rpc.UnexpectedException: Service method 'public abstract java.lang.String com.dbconnect.client.GreetingService.greetServer(java.lang.String) throws java.lang.IllegalArgumentException' threw an unexpected exception: net.sf.json.JSONException: JSONObject["update_seq"] is not a number.
    at com.google.gwt.user.server.rpc.RPC.encodeResponseForFailure(RPC.java:416)
    at com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:605)
    at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:333)
    at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:303)
    at com.google.gwt.user.server.rpc.RemoteServiceServlet.processPost(RemoteServiceServlet.java:373)
    at com.google.gwt.user.server.rpc.AbstractRemoteServiceServlet.doPost(AbstractRemoteServiceServlet.java:62)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:812)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:587)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.handler.RequestLogHandler.handle(RequestLogHandler.java:95)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.Server.handle(Server.java:499)
    at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311)
    at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
    at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:544)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
    at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
    at java.lang.Thread.run(Unknown Source)
Caused by: 
net.sf.json.JSONException: JSONObject["update_seq"] is not a number.
    at net.sf.json.JSONObject.getDouble(JSONObject.java:2090)
    at net.sf.json.JSONObject.getInt(JSONObject.java:2109)
    at com.fourspaces.couchdb.Database.<init>(Database.java:50)
    at com.fourspaces.couchdb.Session.getDatabase(Session.java:185)
    at com.dbconnect.server.GreetingServiceImpl.greetServer(GreetingServiceImpl.java:22)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:587)
    at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:333)
    at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:303)
    at com.google.gwt.user.server.rpc.RemoteServiceServlet.processPost(RemoteServiceServlet.java:373)
    at com.google.gwt.user.server.rpc.AbstractRemoteServiceServlet.doPost(AbstractRemoteServiceServlet.java:62)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:812)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:587)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.handler.RequestLogHandler.handle(RequestLogHandler.java:95)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.Server.handle(Server.java:499)
    at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311)
    at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
    at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:544)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
    at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
    at java.lang.Thread.run(Unknown Source)

/**********************************EDIT 1************************/ Link where mentioned about update_seq

• The thing is we are not updating update_seq through our code its auto has done at the time of creation document in the database. So, don't know whats the issue.

• Forgot to write that database is been created through java easily on CouchDB 2.0.

• Do WE HAVE TO USE NEW VERSIONS OF JAR FILES>?

Answer 1

The problem has to do with couchdb4j being old (last commit on github was nearly 5 years ago).

This post also states this an suggests using a client-library that's more actively worked on e.g. Ektorp (see CouchDB Java client).

Background on the couchbd4j-problem you are facing

The migration documentation you linked (https://blog.couchdb.org/2016/08/17/migrating-to-couchdb-2-0/) states:

Most importantly, the update seq, or sequence, is not a number any longer but a string.

As you said you do not deal with update_seq directly but couchdb4j does.

The current implementation of couchdb4j client-library parses the server-response-property update_seq as Integer using the following code:

updateSeq = json.getInt("update_seq");

And this will no longer work with CouchDb 2.0

Here's a link to the most recent code containing this line: https://github.com/mbreese/couchdb4j/blob/master/src/java/com/fourspaces/couchdb/Database.java (see line 59)

I hope this helped, Christian