Thursday, July 16, 2009

Practical Django Projects, coltrane weblog app and django-tagging

I'm working through Practical Django Projects 2nd Edition.

There is a problem with Chapter 4's weblog application, "coltrane." I won't go into detail about the coltrane app, but in the event that you encounter the same problem I've posted a solution.

I downloaded django-tagging. The current version was 0.2.1.

I created a symlink from my projects directory to the downloaded directory.

I added "'taggigng'" to "INSTALLED_APPS" and tried to start the server. I got the following :
Validating models...
Unhandled exception in thread started by <function inner_run at 0x652c30>
Traceback (most recent call last):
File "/Library/Python/2.5/site-packages/django/core/management/commands/runserver.py", line 48, in inner_run
self.validate(display_num_errors=True)
File "/Library/Python/2.5/site-packages/django/core/management/base.py", line 246, in validate
num_errors = get_validation_errors(s, app)
File "/Library/Python/2.5/site-packages/django/core/management/validation.py", line 28, in get_validation_errors
for (app_name, error) in get_app_errors().items():
File "/Library/Python/2.5/site-packages/django/db/models/loading.py", line 128, in get_app_errors
self._populate()
File "/Library/Python/2.5/site-packages/django/db/models/loading.py", line 57, in _populate
self.load_app(app_name, True)
File "/Library/Python/2.5/site-packages/django/db/models/loading.py", line 72, in load_app
mod = __import__(app_name, {}, {}, ['models'])
File "/[path to django projects]/coltrane/models.py", line 6, in <module>
from tagging.fields import TagField
File "/[path to django projects]/tagging/fields.py", line 10, in <module>
File "/[path to django projects]/tagging/models.py", line 9, in <module>
File "/[path to django projects]/tagging/managers.py", line 6, in <module>
ImportError: cannot import name parse_lookup
Sweet!

Turns out a lot of people have had this problem.

I checked out the current version from svn and recreated the symlink. All was well.

Django syncdb and create/drop

Django's manage.py syncdb command doesn't drop/create. It is clearly stated in the documentation. Naturally it took me a while to figure that out.

There is an easy solution :


python ./Documents/DjangoWorkspace/cms/manage.py reset coltrane
I've used it a few times now.


Creating a build.xml for a JBoss Tools Seam project continued

I posted earlier about a really nice blog entry outlining the differences between JBoss Tools and Seam-Gen generated projects. I grabbed the build.xml the author supplied, saving myself a few hours. However, I ran into an annoying hiccup.

I usually develop with an exploded .ear. The ant target,"explode," worked fine.

I ran the "deploy" target to verify before committing my latest changes. The app wouldn't start.
java.lang.NoClassDefFoundError: org/ajax4jsf/application/ViewHandlerWrapper
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:675)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at org.jboss.mx.loading.RepositoryClassLoader.findClassLocally(RepositoryClassLoader.java:682)
at org.jboss.mx.loading.RepositoryClassLoader.findClass(RepositoryClassLoader.java:662)
at java.lang.ClassLoader.loadClass(ClassLoader.java:316)
at org.jboss.mx.loading.RepositoryClassLoader.loadClassLocally(RepositoryClassLoader.java:200)
at org.jboss.mx.loading.ClassLoadingTask$ThreadTask.run(ClassLoadingTask.java:131)
at org.jboss.mx.loading.LoadMgr3.nextTask(LoadMgr3.java:399)
at org.jboss.mx.loading.RepositoryClassLoader.loadClassImpl(RepositoryClassLoader.java:527)
at org.jboss.mx.loading.RepositoryClassLoader.loadClass(RepositoryClassLoader.java:415)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:374)
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2357)
at java.lang.Class.getConstructor0(Class.java:2671)
at java.lang.Class.newInstance0(Class.java:321)
at java.lang.Class.newInstance(Class.java:303)
at com.sun.faces.config.ConfigureListener.configure(ConfigureListener.java:825)
at com.sun.faces.config.ConfigureListener.configure(ConfigureListener.java:486)
at com.sun.faces.config.ConfigureListener.contextInitialized(ConfigureListener.java:381)
at org.jboss.web.jsf.integration.config.JBossJSFConfigureListener.contextInitialized(JBossJSFConfigureListener.java:69)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3856)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4361)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:790)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:770)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:553)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:296)
at org.jboss.mx.server.RawDynamicInvoker.invoke(RawDynamicInvoker.java:164)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.apache.catalina.core.StandardContext.init(StandardContext.java:5312)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:296)
at org.jboss.mx.server.RawDynamicInvoker.invoke(RawDynamicInvoker.java:164)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.web.tomcat.service.TomcatDeployer.performDeployInternal(TomcatDeployer.java:301)
at org.jboss.web.tomcat.service.TomcatDeployer.performDeploy(TomcatDeployer.java:104)
at org.jboss.web.AbstractWebDeployer.start(AbstractWebDeployer.java:375)
at org.jboss.web.WebModule.startModule(WebModule.java:83)
at org.jboss.web.WebModule.startService(WebModule.java:61)
at org.jboss.system.ServiceMBeanSupport.jbossInternalStart(ServiceMBeanSupport.java:289)
at org.jboss.system.ServiceMBeanSupport.jbossInternalLifecycle(ServiceMBeanSupport.java:245)
at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.system.ServiceController$ServiceProxy.invoke(ServiceController.java:978)
at $Proxy0.start(Unknown Source)
at org.jboss.system.ServiceController.start(ServiceController.java:417)
at sun.reflect.GeneratedMethodAccessor9.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanProxyExt.java:210)
at $Proxy44.start(Unknown Source)
at org.jboss.web.AbstractWebContainer.start(AbstractWebContainer.java:466)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.interceptor.AbstractInterceptor.invoke(AbstractInterceptor.java:133)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.interceptor.ModelMBeanOperationInterceptor.invoke(ModelMBeanOperationInterceptor.java:142)
at org.jboss.mx.interceptor.DynamicInterceptor.invoke(DynamicInterceptor.java:97)
at org.jboss.system.InterceptorServiceMBeanSupport.invokeNext(InterceptorServiceMBeanSupport.java:238)
at org.jboss.wsf.container.jboss42.DeployerInterceptor.start(DeployerInterceptor.java:87)
at org.jboss.deployment.SubDeployerInterceptorSupport$XMBeanInterceptor.start(SubDeployerInterceptorSupport.java:188)
at org.jboss.deployment.SubDeployerInterceptor.invoke(SubDeployerInterceptor.java:95)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanProxyExt.java:210)
at $Proxy45.start(Unknown Source)
at org.jboss.deployment.MainDeployer.start(MainDeployer.java:1025)
at org.jboss.deployment.MainDeployer.start(MainDeployer.java:1015)
at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:819)
at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:782)
at sun.reflect.GeneratedMethodAccessor20.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.interceptor.AbstractInterceptor.invoke(AbstractInterceptor.java:133)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.interceptor.ModelMBeanOperationInterceptor.invoke(ModelMBeanOperationInterceptor.java:142)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanProxyExt.java:210)
at $Proxy9.deploy(Unknown Source)
at org.jboss.deployment.scanner.URLDeploymentScanner.deploy(URLDeploymentScanner.java:421)
at org.jboss.deployment.scanner.URLDeploymentScanner.scan(URLDeploymentScanner.java:634)
at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.doScan(AbstractDeploymentScanner.java:263)
at org.jboss.deployment.scanner.AbstractDeploymentScanner.startService(AbstractDeploymentScanner.java:336)
at org.jboss.system.ServiceMBeanSupport.jbossInternalStart(ServiceMBeanSupport.java:289)
at org.jboss.system.ServiceMBeanSupport.jbossInternalLifecycle(ServiceMBeanSupport.java:245)
at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.system.ServiceController$ServiceProxy.invoke(ServiceController.java:978)
at $Proxy0.start(Unknown Source)
at org.jboss.system.ServiceController.start(ServiceController.java:417)
at sun.reflect.GeneratedMethodAccessor9.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanProxyExt.java:210)
at $Proxy4.start(Unknown Source)
at org.jboss.deployment.SARDeployer.start(SARDeployer.java:302)
at org.jboss.deployment.MainDeployer.start(MainDeployer.java:1025)
at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:819)
at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:782)
at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:766)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.interceptor.AbstractInterceptor.invoke(AbstractInterceptor.java:133)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.interceptor.ModelMBeanOperationInterceptor.invoke(ModelMBeanOperationInterceptor.java:142)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanProxyExt.java:210)
at $Proxy5.deploy(Unknown Source)
at org.jboss.system.server.ServerImpl.doStart(ServerImpl.java:482)
at org.jboss.system.server.ServerImpl.start(ServerImpl.java:362)
at org.jboss.Main.boot(Main.java:200)
at org.jboss.Main$1.run(Main.java:508)
at java.lang.Thread.run(Thread.java:613)
IN
Nice.

I tried again with "explode," and everything was fine. I love these kinds of errors.

I uzipped the .ear file and diffed the resulting folder with the exploded ear folder.

The first difference I noticed was that the MANIFEST.MF in the .ear/META-INF did not contain a Class-Path entry while the exploded one contained an entry with "/lib/groovy-all,jar quartz.jar".

I added a manifest tag to the jar command of the build.xml. The result was :

    <target name="archive" depends="jar,war,ear"
description="Package the archives">
<jar jarfile="${dist.dir}/${project.name}-ejb.jar" basedir="${jar.dir}" />
<jar jarfile="${dist.dir}/${project.name}.war" basedir="${war.dir}" />
<jar jarfile="${dist.dir}/${project.name}.ear">
<manifest >
<attribute name="Class-Path" value="lib/groovy-all.jar quartz.jar"/>
</manifest>
<fileset dir="${ear.dir}" />
<fileset dir="${dist.dir}" >
<include name="${project.name}-ejb.jar" />
<include name="${project.name}.war" />
</fileset>
</jar>
</target>


It didn't matter. I ran "deploy" and got the same error. So I checked the MANIFEST.MF in the ear. Sure enough the exploded one contained a "Class-Path" entry and the archived one didn't.
Adding the "Class-Path" attribute to the manifest fixed it. The result was :

    <target name="archive" depends="jar,war,ear"
description="Package the archives">
<jar jarfile="${dist.dir}/${project.name}-ejb.jar" basedir="${jar.dir}" >
<manifest>
<attribute name="Class-Path" value="antlr-runtime.jar drools-compiler.jar drools-core.jar jboss-el.jar jboss-seam.jar jbpm-jpdl.jar mvel14.jar richfaces-api.jar" />
</manifest>
</jar>
<jar jarfile="${dist.dir}/${project.name}.war" basedir="${war.dir}" />
<jar jarfile="${dist.dir}/${project.name}.ear">
<manifest >
<attribute name="Class-Path" value="lib/groovy-all.jar quartz.jar"/>
</manifest>
<fileset dir="${ear.dir}" />
<fileset dir="${dist.dir}" >
<include name="${project.name}-ejb.jar" />
<include name="${project.name}.war" />
</fileset>
</jar>
</target>


Finally, back to real work.

Friday, July 10, 2009

Creating a build.xml for a JBoss Tools Seam project

I usually use seam-gen to create my Seam projects. I have also been relying on a lot of JBoss Tools. JBoss Tools is a suite of Eclipse plugins.

I created my most recent project using the ide. The generated project does not contain a build.xml. This is of course a problem when you want to automate the build process.

There is a resolved JIRA issue so I imagine this won't be a problem much longer.

In the meantime this really nice blog entry contains a template build.xml.