Atom Feeds with Spring MVC

byJakub Nabrdalik
January 12, 2012
4 minute read

How to add feeds (Atom) to your web application with just two classes? How about Spring MVC? Here are my assumptions: you are using Spring framework you have some entity, say “News”, that you want to publish in your feeds your “News” entity has creationDate, title, and shortDescription you have some repository/dao, say “NewsRepository”, that will return the news from your database you want to write as little as possible you don’t want to format Atom (xml) by hand You actually do NOT need to use Spring MVC in your application already. If you do, skip to step 3. Step 1: add Spring MVC dependency to your application With maven that will be: <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>3.1.0.RELEASE</version> </dependency> Step 2: add Spring MVC DispatcherServlet With web.xml that would be: <servlet> <servlet-name>dispatcher</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-mvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>dispatcher</servlet-name> <url-pattern>/feed</url-pattern> </servlet-mapping> Notice, I set the url-pattern to “/feed” which means I don’t want Spring MVC to handle any other urls in my app (I’m using a different web framework for the rest of the app). I also give it a brand new contextConfigLocation, where only the mvc configuration is kept. Remember that, when you add a DispatcherServlet to an app that already has Spring (from ContextLoaderListener for example), your context is inherited from the global one, so you should not create beans that exist there again, or include xml that defines them. Watch out for Spring context getting up twice, and refer to spring or servlet documentation to understand what’s happaning. Step 3. add ROME – a library to handle Atom format With maven that is: <dependency> <groupId>net.java.dev.rome</groupId> <artifactId>rome</artifactId> <version>1.0.0</version> </dependency> Step 4. write your very simple controller @Controller public class FeedController { static final String LAST_UPDATE_VIEW_KEY = "lastUpdate"; static final String NEWS_VIEW_KEY = "news"; private NewsRepository newsRepository; private String viewName; protected FeedController() {} //required by cglib public FeedController(NewsRepository newsRepository, String viewName) { notNull(newsRepository); hasText(viewName); this.newsRepository = newsRepository; this.viewName = viewName; } @RequestMapping(value = "/feed", method = RequestMethod.GET) @Transactional public ModelAndView feed() { ModelAndView modelAndView = new ModelAndView(); modelAndView.setViewName(viewName); List<News> news = newsRepository.fetchPublished(); modelAndView.addObject(NEWS_VIEW_KEY, news); modelAndView.addObject(LAST_UPDATE_VIEW_KEY, getCreationDateOfTheLast(news)); return modelAndView; } private Date getCreationDateOfTheLast(List<News> news) { if(news.size() > 0) { return news.get(0).getCreationDate(); } return new Date(0); } } And here’s a test for it, in case you want to copy&paste (who doesn’t?): @RunWith(MockitoJUnitRunner.class) public class FeedControllerShould { @Mock private NewsRepository newsRepository; private Date FORMER_ENTRY_CREATION_DATE = new Date(1); private Date LATTER_ENTRY_CREATION_DATE = new Date(2); private ArrayList<News> newsList; private FeedController feedController; @Before public void prepareNewsList() { News news1 = new News().title("title1").creationDate(FORMER_ENTRY_CREATION_DATE); News news2 = new News().title("title2").creationDate(LATTER_ENTRY_CREATION_DATE); newsList = newArrayList(news2, news1); } @Before public void prepareFeedController() { feedController = new FeedController(newsRepository, "viewName"); } @Test public void returnViewWithNews() { //given given(newsRepository.fetchPublished()).willReturn(newsList); //when ModelAndView modelAndView = feedController.feed(); //then assertThat(modelAndView.getModel()) .includes(entry(FeedController.NEWS_VIEW_KEY, newsList)); } @Test public void returnViewWithLastUpdateTime() { //given given(newsRepository.fetchPublished()).willReturn(newsList); //when ModelAndView modelAndView = feedController.feed(); //then assertThat(modelAndView.getModel()) .includes(entry(FeedController.LAST_UPDATE_VIEW_KEY, LATTER_ENTRY_CREATION_DATE)); } @Test public void returnTheBeginningOfTimeAsLastUpdateInViewWhenListIsEmpty() { //given given(newsRepository.fetchPublished()).willReturn(new ArrayList<News>()); //when ModelAndView modelAndView = feedController.feed(); //then assertThat(modelAndView.getModel()) .includes(entry(FeedController.LAST_UPDATE_VIEW_KEY, new Date(0))); } } Notice: here, I’m using fest-assert and mockito. The dependencies are: <dependency> <groupId>org.easytesting</groupId> <artifactId>fest-assert</artifactId> <version>1.4</version> <scope>test</scope> </dependency> <dependency> <groupId>org.mockito</groupId> <artifactId>mockito-all</artifactId> <version>1.8.5</version> <scope>test</scope> </dependency> Step 5. write your very simple view Here’s where all the magic formatting happens. Be sure to take a look at all the methods of Entry class, as there is quite a lot you may want to use/fill. import org.springframework.web.servlet.view.feed.AbstractAtomFeedView; [...] public class AtomFeedView extends AbstractAtomFeedView { private String feedId = "tag:yourFantastiSiteName"; private String title = "yourFantastiSiteName: news"; private String newsAbsoluteUrl = "http://yourfanstasticsiteUrl.com/news/"; @Override protected void buildFeedMetadata(Map<String, Object> model, Feed feed, HttpServletRequest request) { feed.setId(feedId); feed.setTitle(title); setUpdatedIfNeeded(model, feed); } private void setUpdatedIfNeeded(Map<String, Object> model, Feed feed) { @SuppressWarnings("unchecked") Date lastUpdate = (Date)model.get(FeedController.LAST_UPDATE_VIEW_KEY); if (feed.getUpdated() == null || lastUpdate != null || lastUpdate.compareTo(feed.getUpdated()) > 0) { feed.setUpdated(lastUpdate); } } @Override protected List<Entry> buildFeedEntries(Map<String, Object> model, HttpServletRequest request, HttpServletResponse response) throws Exception { @SuppressWarnings("unchecked") List<News> newsList = (List<News>)model.get(FeedController.NEWS_VIEW_KEY); List<Entry> entries = new ArrayList<Entry>(); for (News news : newsList) { addEntry(entries, news); } return entries; } private void addEntry(List<Entry> entries, News news) { Entry entry = new Entry(); entry.setId(feedId + ", " + news.getId()); entry.setTitle(news.getTitle()); entry.setUpdated(news.getCreationDate()); entry = setSummary(news, entry); entry = setLink(news, entry); entries.add(entry); } private Entry setSummary(News news, Entry entry) { Content summary = new Content(); summary.setValue(news.getShortDescription()); entry.setSummary(summary); return entry; } private Entry setLink(News news, Entry entry) { Link link = new Link(); link.setType("text/html"); link.setHref(newsAbsoluteUrl + news.getId()); //because I have a different controller to show news at http://yourfanstasticsiteUrl.com/news/ID entry.setAlternateLinks(newArrayList(link)); return entry; } } Step 6. add your classes to your Spring context I’m using xml approach. because I’m old and I love xml. No, seriously, I use xml because I may want to declare FeedController a few times with different views (RSS 1.0, RSS 2.0, etc.). So this is the forementioned spring-mvc.xml <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver"> <property name="mediaTypes"> <map> <entry key="atom" value="application/atom+xml"/> <entry key="html" value="text/html"/> </map> </property> <property name="viewResolvers"> <list> <bean class="org.springframework.web.servlet.view.BeanNameViewResolver"/> </list> </property> </bean> <bean class="eu.margiel.pages.confitura.feed.FeedController"> <constructor-arg index="0" ref="newsRepository"/> <constructor-arg index="1" value="atomFeedView"/> </bean> <bean id="atomFeedView" class="eu.margiel.pages.confitura.feed.AtomFeedView"/> </beans> And you are done. I’ve been asked a few times before to put all the working code in some public repo, so this time it’s the other way around. I’ve describe things that I had already published, and you can grab the commit from the bitbucket. Hope that helps.

How to add feeds (Atom) to your web application with just two classes?
How about Spring MVC?

Here are my assumptions:

you are using Spring framework
you have some entity, say “News”, that you want to publish in your feeds
your “News” entity has creationDate, title, and shortDescription
you have some repository/dao, say “NewsRepository”, that will return the news from your database
you want to write as little as possible
you don’t want to format Atom (xml) by hand

You actually do NOT need to use Spring MVC in your application already. If you do, skip to step 3.

Step 1: add Spring MVC dependency to your application
With maven that will be:

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>3.1.0.RELEASE</version>
</dependency>

Step 2: add Spring MVC DispatcherServlet
With web.xml that would be:

<servlet>
    <servlet-name>dispatcher</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:spring-mvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>dispatcher</servlet-name>
    <url-pattern>/feed</url-pattern>
</servlet-mapping>

Notice, I set the url-pattern to “/feed” which means I don’t want Spring MVC to handle any other urls in my app (I’m using a different web framework for the rest of the app). I also give it a brand new contextConfigLocation, where only the mvc configuration is kept.

Remember that, when you add a DispatcherServlet to an app that already has Spring (from ContextLoaderListener for example), your context is inherited from the global one, so you should not create beans that exist there again, or include xml that defines them. Watch out for Spring context getting up twice, and refer to spring or servlet documentation to understand what’s happaning.

Step 3. add ROME – a library to handle Atom format
With maven that is:

<dependency>
    <groupId>net.java.dev.rome</groupId>
    <artifactId>rome</artifactId>
    <version>1.0.0</version>
</dependency>

Step 4. write your very simple controller

@Controller
public class FeedController {
    static final String LAST_UPDATE_VIEW_KEY = "lastUpdate";
    static final String NEWS_VIEW_KEY = "news";
    private NewsRepository newsRepository;
    private String viewName;

    protected FeedController() {} //required by cglib

    public FeedController(NewsRepository newsRepository, String viewName) {
        notNull(newsRepository); hasText(viewName);
        this.newsRepository = newsRepository;
        this.viewName = viewName;
    }

    @RequestMapping(value = "/feed", method = RequestMethod.GET)        
    @Transactional
    public ModelAndView feed() {
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.setViewName(viewName);
        List<News> news = newsRepository.fetchPublished();
        modelAndView.addObject(NEWS_VIEW_KEY, news);
        modelAndView.addObject(LAST_UPDATE_VIEW_KEY, getCreationDateOfTheLast(news));
        return modelAndView;
    }

    private Date getCreationDateOfTheLast(List<News> news) {
        if(news.size() > 0) {
            return news.get(0).getCreationDate();
        }
        return new Date(0);
    }
}

And here’s a test for it, in case you want to copy&paste (who doesn’t?):

@RunWith(MockitoJUnitRunner.class)
public class FeedControllerShould {
    @Mock private NewsRepository newsRepository;
    private Date FORMER_ENTRY_CREATION_DATE = new Date(1);
    private Date LATTER_ENTRY_CREATION_DATE = new Date(2);
    private ArrayList<News> newsList;
    private FeedController feedController;

    @Before
    public void prepareNewsList() {
        News news1 = new News().title("title1").creationDate(FORMER_ENTRY_CREATION_DATE);
        News news2 = new News().title("title2").creationDate(LATTER_ENTRY_CREATION_DATE);
        newsList = newArrayList(news2, news1);
    }

    @Before
    public void prepareFeedController() {
        feedController = new FeedController(newsRepository, "viewName");
    }

    @Test
    public void returnViewWithNews() {
        //given
        given(newsRepository.fetchPublished()).willReturn(newsList);
        
        //when
        ModelAndView modelAndView = feedController.feed();
        
        //then
        assertThat(modelAndView.getModel())
                .includes(entry(FeedController.NEWS_VIEW_KEY, newsList));
    }

    @Test
    public void returnViewWithLastUpdateTime() {
        //given
        given(newsRepository.fetchPublished()).willReturn(newsList);

        //when
        ModelAndView modelAndView = feedController.feed();

        //then
        assertThat(modelAndView.getModel())
                .includes(entry(FeedController.LAST_UPDATE_VIEW_KEY, LATTER_ENTRY_CREATION_DATE));
    }

    @Test
    public void returnTheBeginningOfTimeAsLastUpdateInViewWhenListIsEmpty() {
        //given
        given(newsRepository.fetchPublished()).willReturn(new ArrayList<News>());

        //when
        ModelAndView modelAndView = feedController.feed();

        //then
        assertThat(modelAndView.getModel())
                .includes(entry(FeedController.LAST_UPDATE_VIEW_KEY, new Date(0)));
    }
}

Notice: here, I’m using fest-assert and mockito. The dependencies are:

<dependency>
 <groupId>org.easytesting</groupId>
 <artifactId>fest-assert</artifactId>
 <version>1.4</version>
 <scope>test</scope>
</dependency>
<dependency>
 <groupId>org.mockito</groupId>
 <artifactId>mockito-all</artifactId>
 <version>1.8.5</version>
 <scope>test</scope>
</dependency>

Step 5. write your very simple view
Here’s where all the magic formatting happens. Be sure to take a look at all the methods of Entry class, as there is quite a lot you may want to use/fill.

import org.springframework.web.servlet.view.feed.AbstractAtomFeedView;
[...]

public class AtomFeedView extends AbstractAtomFeedView {
    private String feedId = "tag:yourFantastiSiteName";
    private String title = "yourFantastiSiteName: news";
    private String newsAbsoluteUrl = "http://yourfanstasticsiteUrl.com/news/"; 

    @Override
    protected void buildFeedMetadata(Map<String, Object> model, Feed feed, HttpServletRequest request) {
        feed.setId(feedId);
        feed.setTitle(title);
        setUpdatedIfNeeded(model, feed);
    }

    private void setUpdatedIfNeeded(Map<String, Object> model, Feed feed) {
        @SuppressWarnings("unchecked")
        Date lastUpdate = (Date)model.get(FeedController.LAST_UPDATE_VIEW_KEY);
        if (feed.getUpdated() == null || lastUpdate != null || lastUpdate.compareTo(feed.getUpdated()) > 0) {
            feed.setUpdated(lastUpdate);
        }
    }

    @Override
    protected List<Entry> buildFeedEntries(Map<String, Object> model, HttpServletRequest request, HttpServletResponse response) throws Exception {
        @SuppressWarnings("unchecked")
        List<News> newsList = (List<News>)model.get(FeedController.NEWS_VIEW_KEY);
        List<Entry> entries = new ArrayList<Entry>();
        for (News news : newsList) {
            addEntry(entries, news);
        }
        return entries;
    }

    private void addEntry(List<Entry> entries, News news) {
        Entry entry = new Entry();
        entry.setId(feedId + ", " + news.getId());
        entry.setTitle(news.getTitle());
        entry.setUpdated(news.getCreationDate());
        entry = setSummary(news, entry);
        entry = setLink(news, entry);
        entries.add(entry);
    }

    private Entry setSummary(News news, Entry entry) {
        Content summary = new Content();
        summary.setValue(news.getShortDescription());
        entry.setSummary(summary);
        return entry;
    }

    private Entry setLink(News news, Entry entry) {
        Link link = new Link();
        link.setType("text/html");
        link.setHref(newsAbsoluteUrl + news.getId()); //because I have a different controller to show news at http://yourfanstasticsiteUrl.com/news/ID
        entry.setAlternateLinks(newArrayList(link));
        return entry;
    }

}

Step 6. add your classes to your Spring context
I’m using xml approach. because I’m old and I love xml. No, seriously, I use xml because I may want to declare FeedController a few times with different views (RSS 1.0, RSS 2.0, etc.).

So this is the forementioned spring-mvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
        <property name="mediaTypes">
            <map>
                <entry key="atom" value="application/atom+xml"/>
                <entry key="html" value="text/html"/>
            </map>
        </property>
        <property name="viewResolvers">
            <list>
                <bean class="org.springframework.web.servlet.view.BeanNameViewResolver"/>
            </list>
        </property>
    </bean>

    <bean class="eu.margiel.pages.confitura.feed.FeedController">
        <constructor-arg index="0" ref="newsRepository"/>
        <constructor-arg index="1" value="atomFeedView"/>
    </bean>

    <bean id="atomFeedView" class="eu.margiel.pages.confitura.feed.AtomFeedView"/>
</beans>

And you are done.

I’ve been asked a few times before to put all the working code in some public repo, so this time it’s the other way around. I’ve describe things that I had already published, and you can grab the commit from the bitbucket.

Hope that helps.

Jakub Nabrdalik

Solution Architect @ TouK

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Bash'ing your git deployment

CasperJS for Java developers

byPiotr Jagielski
January 28, 2013

Why CasperJS

Being a Java developer is kinda hard these days. Java may not be dead yet, but when keeping in sync with all the hipster JavaScript frameworks could make us feel a bit outside the playground. It’s even hard to list JavaScript frameworks with latest releases on one website.

In my current project, we are using AngularJS. It’a a nice abstraction of MV* pattern in frontend layer of any web application (we use Grails underneath). Here is a nice article with an 8-point Win List of Angular way of handling AJAX calls and updating the view. So it’s not only a funny new framework but a truly helper of keeping your code clean and neat.

But there is also another area when you can put helpful JS framework in place of plan-old-java one - functional tests. Especially when you are dealing with one page app with lots of asynchronous REST/JSON communication.

Selenium and Geb

In Java/JVM project the typical is to use Selenium with some wrapper like Geb. So you start your project, setup your CI-functional testing pipeline and… after 1 month of coding your tests stop working and being maintainable. The frameworks itselves are not bad, but the typical setup is so heavy and has so many points of failure that keeping it working in a real life project is really hard.

Here is my list of common myths about Selenium: * It allows you to record test scripts via handy GUI - maybe some static request/response sites. In modern web applications with asynchronous REST/JSON communication your tests must contain a lot of “waitFor” statements and you cannot automate where these should be included. * It allows you to test your web app against many browsers - don’t try to automate IE tests! You have to manually open your app in IE to see how it actually bahaves! * It integrates well with continuous integration servers like Jenkins - you have to setup Selenium Grid on server with X installed to run tests on Chrome or Firefox and a Windows server for IE. And the headless HtmlUnit driver lacks a lot of JS support.

So I decided to try something different and introduce a bit of JavaScript tooling in our project by using CasperJS.

Introduction

CasperJS is simple but powerful navigation scripting & testing utility for PhantomJS - scritable headless WebKit (which is an rendering engine used by Safari and Chrome). In short - CasperJS allows you to navigate and make assertions about web pages as they’d been rendered in Google Chrome. It is enough for me to automate the functional tests of my application.

If you want a gentle introduction to the world of CasperJS I suggest you to read: * Official website, especially installation guide and API * Introductionary article from CasperJS creator Nicolas Perriault * Highlevel testing with CasperJS by Kevin van Zonneveld * grails-angular-scaffolding plugin by Rob Fletcher with some working CasperJS tests

Full example

I run my test suite via following script:

casperjs test --direct --log-level=debug --testhost=localhost:8080 --includes=test/casper/includes/casper-angular.coffee,test/casper/includes/pages.coffee test/casper/specs/

casper-angular.coffe

casper.test.on "fail", (failure) ->
    casper.capture(screenshot)

testhost   = casper.cli.get "testhost"
screenshot = 'test-fail.png'

casper
    .log("Using testhost: #{testhost}", "info")
    .log("Using screenshot: #{screenshot}", "info")

casper.waitUntilVisible = (selector, message, callback) ->
    @waitFor ->
        @visible selector
    , callback, (timeout) ->
        @log("Selector [#{selector}] not visible, failing")
        withParentSelector selector, (parent) ->
            casper.log("Output of parent selector [#{parent}]")
            casper.debugHTML(parent)
        @echo message, "RED_BAR"
        @capture(screenshot)
        @test.fail(f("Wait timeout occured (%dms)", timeout))

withParentSelector = (selector, callback) ->
    if selector.lastIndexOf(" ") > 0
       parent = selector[0..selector.lastIndexOf(" ")-1]
       callback(parent)

Sample pages.coffee:

x = require('casper').selectXPath

class EditDocumentPage

    assertAt: ->
        casper.test.assertSelectorExists("div.customerAccountInfo", 'at EditDocumentPage')

    templatesTreeFirstCategory: 'ul.tree li label'
    templatesTreeFirstTemplate: 'ul.tree li a'
    closePreview: '.closePreview a'
    smallPreview: '.smallPreviewContent img'
    bigPreview: 'img.previewImage'
    confirmDelete: x("//div[@class='modal-footer']/a[1]")

casper.editDocument = new EditDocumentPage()

End a test script:

testhost = casper.cli.get "testhost" or 'localhost:8080'

casper.start "http://#{testhost}/app", ->
    @test.assertHttpStatus 302
    @test.assertUrlMatch /\/fakeLogin/, 'auto login'
    @test.assert @visible('input#Create'), 'mock login button'
    @click 'input#Create'

casper.then ->
    @test.assertUrlMatch /document#\/edit/, 'new document'
    @editDocument.assertAt()
    @waitUntilVisible @editDocument.templatesTreeFirstCategory, 'template categories not visible', ->
        @click @editDocument.templatesTreeFirstCategory
        @waitUntilVisible @editDocument.templatesTreeFirstTemplate, 'template not visible', ->
            @click @editDocument.templatesTreeFirstTemplate

casper.then ->
    @waitUntilVisible @editDocument.smallPreview, 'small preview not visible', ->
        # could be dblclick / whatever
        @mouseEvent('click', @editDocument.smallPreview)

casper.then ->
    @waitUntilVisible @editDocument.bigPreview, 'big preview should be visible', ->
        @test.assertEvalEquals ->
            $('.pageCounter').text()
        , '1/1', 'page counter should be visible'
        @click @editDocument.closePreview

casper.then ->
    @click 'button.cancel'
    @waitUntilVisible '.modal-footer', 'delete confirmation not visible', ->
        @click @editDocument.confirmDelete

casper.run ->
    @test.done()

Here is a list of CasperJS features/caveats used here:

Using CoffeeScript is a huge win for your test code to look neat
When using casper test command, beware of different (than above articles) logging setup. You can pass --direct --log-level=debug from commandline for best results. Logging is essential here since Phantom often exists without any error and you do want to know what just happened.
Extract your helper code into separate files and include them by using --includes switch.
When passing server URL as a commandline switch remember that in CoffeeScript variables are not visible between multiple source files (unless getting them via window object)
It’s good to override standard waitUntilVisible with capting a screenshot and making a proper log statement. In my version I also look for a parent selector and debugHTML the content of it - great for debugging what is actually rendered by the browser.
Selenium and Geb have a nice concept of Page Objects - an abstract models of pages rendered by your application. Using CoffeeScript you can write your own classes, bind selectors to properties and use then in your code script. Assigning the objects to casper instance will end up with quite nice syntax like @editDocument.assertAt().
There is some issue with CSS :first and :last selectors. I cannot get them working (but maybe I’m doing something wrong?). But in CasperJS you can also use XPath selectors which are fine for matching n-th child of some element (x("//div[@class='modal-footer']/a[1]")).
Update: :first and :last are not CSS3 selectors, but JQuery ones. Here is a list of CSS3 selectors, all of these are supported by CasperJS. So you can use nth-child(1) is this case. Thanks Andy and Nicolas for the comments!

Working with CasperJS can lead you to a few hour stall, but after getting things working you have a new, cool tool in your box!

DDevelopment & Design

K_v(x)

bypawelz
March 27, 2011

I have just wasted about three hours of sunday afternoon trying to compute a modified bessel function of…

DDevelopment & Design

New HTTP Logger Grails plugin

byTomasz Kalkosiński
May 7, 2013

I've wrote a new Grails plugin - httplogger. It logs:

request information (url, headers, cookies, method, body),
grails dispatch information (controller, action, parameters),
response information (elapsed time and body).

It is mostly useful for logging your REST traffic. Full HTTP web pages can be huge to log and generally waste your space. I suggest to map all of your REST controllers with the same path in UrlMappings, e.g. /rest/ and configure this plugin with this path.

Here is some simple output just to give you a taste of it.

17:16:00,331 INFO  filters.LogRawRequestInfoFilter  - 17:16:00,340 INFO  filters.LogRawRequestInfoFilter  - 17:16:00,342 INFO  filters.LogGrailsUrlsInfoFilter  - 17:16:00,731 INFO  filters.LogOutputResponseFilter  - >> #1 returned 200, took 405 ms.
17:16:00,745 INFO  filters.LogOutputResponseFilter  - >> #1 responded with '{count:0}'

17:18:55,799 INFO  filters.LogRawRequestInfoFilter  - 17:18:55,799 INFO  filters.LogRawRequestInfoFilter  - 17:18:55,800 INFO  filters.LogRawRequestInfoFilter  - 17:18:55,801 INFO  filters.LogOutputResponseFilter  - >> #2 returned 404, took 3 ms.
17:18:55,802 INFO  filters.LogOutputResponseFilter  - >> #2 responded with ''

Official plugin information can be found on Grails plugins website here: http://grails.org/plugins/httplogger or you can browse code on github: TouK/grails-httplogger.