I have a GWT project that contains both the GWT UI and the server backend. The server backend contains the Java GWT Services that are exposed via GWT's RPC to the UI.
Since the project has grown quite a bit, with the backend requiring more and more time to start, I am considering moving the UI to a separate project, with the idea to run the backend in a separate VM. The backend is relatively stable, and it is the UI where we spent most time. With the two in separate VMs, we could work on the UI much more efficiently, since we would only reload the UI (in GWT development mode) and leave the backend running.
My question: Is it possible to configure the Google Eclipse Plugin in such a way that it runs the UI and backend in separate VMs and I can still use the GWT development mode?
The project uses GWT 2.4 and we will update to 2.5 as soon as it is out. We use Maven as the build system.
There are two things to consider:
You don't always have to reload the server - usually it's enough to just reload the browser page [*] For an overview of when to reload/restart, ... please see https://stackoverflow.com/a/6150736/291741
You can deploy to an external server. In an Eclipse Run Configuration, go to the Server tab, and uncheck "Run built-in server". This will disable the web server (default port 8888), but will still run the Code Server (default port 9997, see the GWT tab). Then just run your external server (e.g. Tomcat) on port 8888. It should serve the web content, and handle the servlet requests.
If you want to create a really cool fully automated Eclipse-JavaEE + GWT setup, with separate server-side redeploy on any server you like (even with two debugger instances, if you want), see https://stackoverflow.com/a/11700678/291741
[*] I know, there are certain situations, e.g. when changing Gin configuration or Validation annotations, where reloading the web page is unfortunately not enough. But in most cases it just works fine (as long as you run DevMode with "Run As...", not with "Debug As...") If you want to run with a debugger attached, then I'd recommend the external server solution, of course.
Related
We are building a project and will be using gwt 2.7 with rest ( spring) and weblogic server.
The problem which we face is that I want to run the gwt module on superdev mode (which runs on 8888 port by default) but the rest is deployed on 7001 port on weblogic server.
I cannot call the rest services from superdev mode as it gives a cross site scripting error.
How can get my super dev mode running so that I can test and develop UI and connect to rest services on different port.
I know there has been topic on use a different server for dev mode. But i don't see any examples.
Can some please suggest wat needs to be done. Even if it requires changing the project structure to get the dev mode working with rest.
This is a common problem for web-development. It can be solved by using:
CORS (at the REST server)
Using a proxy servlet (I use this approach, but with a handwritten servlet)
Disable the browser security (I would not do this)
did you try running GWT module on external server mode?
The project I work at is quite specific. We use GWT with SAP backend. We run the Dev Mode using the following configuration (as program arguments; I run the project directly using IntelliJ IDEA)
-noserver -logLevel INFO -startupUrl http://server-url:8000/aaa -whitelist ^http[:][/][/]server-url[.]eu[:]8000/aaa com.company.project.main.Main
Note, we didn't use a local server (-noserver).
After familiarizing myself with the Super Dev Mode, I understood, that it works similar to GWT Web Mode, i.e. it compiles JavaScript (the folder to compile to can be specified) and then runs the code server with that script hosted.
Due to the specifics of the project, the compiled JavaScript is deployed to the remote server using maven via WebDav. So simply specifying -workDir as a parameter will not deploy the scripts on the remote server. Nor can we run (at least at the moment) a Java server on the server-url address.
Can we use the Super Dev Mode in this situation?
Yes you can.
EDIT 2016-11-27: I built a devserver that can use -launcherDir-style SuperDevMode without the need to write to the server, by using a webpack-like proxy: https://github.com/tbroyer/gwt-devserver
EDIT: there are a few issues re. deferred-binding properties. The recommended use of SDM (since GWT 2.7) is to use -launcherDir which means using a local server.
SuperDevMode works much like DevMode with -noserver, which means you have to deploy your app at least once to your server. In the case of SuperDevMode, it means you have to compile and deploy with the xsiframe linker and devModeRedirectEnabled property set to true.
Then you run SuperDevMode on your machine, create your bookmarklets if not done already, load your app from the remote server and click the Dev Mode On bookmarklet.
This will store something in the browser's sessionStorage so that reloading the page will now load the permutation from the SuperDevMode running on your machine rather than the remote server.
More info about how SuperDevMode works: http://blog.ltgt.net/how-does-gwts-super-dev-mode-work/
For now, I see only one possible solution, which is to run the gwt-codeserver.jar somehow on the SAP server (with the address, say, http://server-url:8000/bbb) and write a servlet, that will redirect all requests to http://server-url:8000/aaa. However, this is not very easy to implement. The SAP server has "tricky" authentication mechanism, where user first sees the logon page and then they are redirected to a generated session-specific URL.
Other ideas are very welcome.
I'm building a web app with Backbone.js (I'm not tied to Backbone yet though). I need a back-end framework only for persistence to a database via a RESTful API. However, I also need to able to deploy it as a 'desktop' app for off-line use, i.e. running a local server and launching a browser window, but I don't want users to have to start a server from the command line to run the application.
I can use SQLite as a database since it's only a single user application, it's just the framework that I'm stuck on. I have looked at the following:
Rails and Django: Default web servers are too flimsy, requires Ruby/Python and runs from the command line. I'm aware of the Bitnami stacks but at 99mb it's too big of a dependency and not exactly hidden from the user.
Sproutcore: Run from command line, also too bulky.
Pyjamas Desktop - Depends on MSHTML which I suspect limits my ability to use HTML5 features.
I'm leaning towards creating a Java app that starts a Scala/Lift server instance and opens a web browser, then sits in the system tray (kind of like WAMP). Is anyone familiar with a tool or framework built for user-friendly deployment as a standalone desktop app?
I do not know if PHP is an option for you? Then I would recommend phpdock.
web2py has a standalone deploy-to-desktop feature with no dependency on Python: http://web2py.com/books/default/chapter/29/14#How-to-distribute-your-applications-as-binaries
As Eydun said, phpdock is an option but it's commercially licensed .
I settled on using Java/Spring/H2/Hibernate/Jetty. I find that Jetty serves requests VERY quickly so the application looks real-time when launched in a browser. There is a tutorial on embedding the Jetty server here. I imagine it's quite trivial to build a GUI that launches the server and a browser.
Another Java option is to use the Play Framework, which may be more at home to those coming from a Django/Rails background. However, the documentation for "creating a standalone version of your application" for Play 2.0+ indicates that they have ditched using Java EE containers (Tomcat/Jetty) and WAR files in favor of running the JARs with the bundled copy of JBoss Netty, so it may take a bit of work to get it running the way you want it.
I would recommend the Play Framework approach if you're OK with using/learning Scala.
I'm developing an application using the Vaadin framework in Eclipse. I'm using the Tomcat v6.0 servlet and run the application in the Eclipse Web Browser. A problem I've been having though is to have recent changes show in the browser when I test the application.
No matter how many times I restart Tomcat, clean all published resources and restart the Eclipse Web Browser the changes still won't take effect. The changes seem to take effect randomly where time is the biggest factor, which is of great frustration when developing...
So my question is if anyone else has noticed this problem and have any ideas of how to solve it, if there is a configuration I can do or if I'm missing a step in the restart which blocks the changes from taking effect..?
Any help would be greatly appreciated!
In Vaadin most of the code runs in the server and is contained in normal Java files. There are three levels of resource/class changes:
The runtime "hot code replacement". If running Tomcat in debug mode some Java class changes can be published without redeploying the web application. However, if the Tomcat is configured to "auto publish" (check your server settings in Eclipse), the redeployment is automatically done whenever classes change and this causes full context reload and sessions serialization (see #2) . Hot code replacement can be enhanced using tools like JRebel.
Web application deployment. This is essentially deploying a new war file to the server. Causes the previous version to be undeployed and deploys the new version of all classes and resources. Sometimes there are some resources left in the servers work directory or classes are not reloaded, in which case the server restart (#3) is needed.
Server restart. This makes the whole JVM to reload and all the classes and web applications are also reloaded. Still cleaning the work directory separately is needed to make sure everything is reloaded.
In addition to this there is the client-side part of Vaadin (essentially a JavaScript compiled with GWT), which is treated as a static resource by Tomcat. If you modify the client-side Java code the GWT is used to recompile the JavaScript. Deployment should be simply file copying. The browsers cache the generated HTML/JS files, but GWT includes mechanism to avoid this.
You should first try to change the server settings for automatic publishing and see if that helps. Also, I've noticed that different Tomcat version behave differently. This is unfortunate, but the only thing you can do is to try to find the versions/set-up that works for you.
Just to make sure: you have been adding ?restartApplication in the URL to force application to restart on page reload, haven't you?
I'm thinking about an application where in some cases both client and server would run on customer's computer. Concerning the client's resource usage I've found this question, concerning the general disadvantages of GWT I've found this, but I can't find anything about the overhead of the server part. I need no application server there, anything capable of running the server part of GWT would do.
What is needed to run the server part of GWT and how many resources it consumes?
If you use a ServiceImpl w/ your GWT app, you need to deploy it into a servlet container, like Tomcat or Jetty (or many others). Otherwise, it can be deployed on any web server, as it will only consist of javascript, HTML, and CSS.