More extensions:

10. Navigation
11. Restricting pages to logged in users only

README.txt

@@ -96,4 +96,22 @@ By Gaving King, see http://in.relation.to/13053.lace.
 A component for enqueing faces messages, which will survive redirects. Use:
 
 @Inject
-private FacesMessages facesMessages;
+private FacesMessages facesMessages;
+
+10. Navigation
+
+Extend the NavBase to create a "nav" component and define any pages that you use the following way, using the PageBuilder:
+
+private final Page page1 = new PageBuilder("/page1.xhtml").setRequiresLogin(true).b();
+private final Page login = new PageBuilder("/login.xhtml").b();
+...
+
+And define a getter for each page.
+
+You can then use the component either to return results of action methods or to create links:
+
+<h:link outcome="#{nav.page1.s}">Page 1</h:link>
+
+11. Restricting pages to logged in users only
+
+There must be a bean implementing the LoginBean interface; the bean controls if there's a logged in user.

src/main/java/pl/softwaremill/cdiext/navigation/NavBase.java

@@ -0,0 +1,54 @@
+package pl.softwaremill.cdiext.navigation;
+
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+/**
+ * @author Adam Warski (adam at warski dot org)
+ */
+public abstract class NavBase {
+    private Map<String, Page> pagesByViewId= new HashMap<String, Page>();
+
+    public void register(String viewId, Page page) {
+        pagesByViewId.put(viewId, page);
+    }
+
+    public Page lookup(String viewId) {
+        Page p = pagesByViewId.get(viewId);
+        if (p == null) {
+            throw new RuntimeException("Page with view id " + viewId + " not found.");
+        }
+        return p;
+    }
+
+    protected class PageBuilder {
+        private final String viewId;
+
+        private boolean requiresLogin;
+
+        public PageBuilder(String viewId) {
+            this.viewId = viewId;
+            requiresLogin = false;
+        }
+
+        public PageBuilder setRequiresLogin(boolean requiresLogin) {
+            this.requiresLogin = requiresLogin;
+            return this;
+        }
+
+        public Page b() {
+            Page p = new Page(viewId, new LinkedHashMap<String, String>(), requiresLogin);
+            register(viewId, p);
+            return p;
+        }
+    }
+
+    private final Page currentPage = new PageBuilder("").b();
+
+    public Page getCurrentPage() {
+        return currentPage;
+    }
+
+    public abstract Page getLogin();
+}

src/main/java/pl/softwaremill/cdiext/navigation/Page.java

@@ -0,0 +1,88 @@
+package pl.softwaremill.cdiext.navigation;
+
+import javax.faces.FacesException;
+import javax.faces.component.UIComponent;
+import javax.faces.component.UIViewParameter;
+import javax.faces.component.UIViewRoot;
+import javax.faces.context.FacesContext;
+import javax.faces.view.ViewDeclarationLanguage;
+import javax.faces.view.ViewMetadata;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+/**
+ * @author Adam Warski (adam at warski dot org)
+ */
+public class Page {
+    private final String viewId;
+    private final Map<String, String> params;
+    private final boolean requiresLogin;
+
+    public Page(String viewId, Map<String, String> params, boolean requiresLogin) {
+        this.viewId = viewId;
+        this.params = params;
+        this.requiresLogin = requiresLogin;
+    }
+
+    public Page redirect() {
+        return includeParam("faces-redirect", "true");
+    }
+
+    public Page includeViewParams() {
+        return includeParam("includeViewParams", "true");
+    }
+
+    public Page includeViewParam(String name) {
+        // Getting the metadata facet of the view
+        FacesContext ctx = FacesContext.getCurrentInstance();
+        ViewDeclarationLanguage vdl = ctx.getApplication().getViewHandler().getViewDeclarationLanguage(ctx, viewId);
+        ViewMetadata viewMetadata = vdl.getViewMetadata(ctx, viewId);
+        UIViewRoot viewRoot = viewMetadata.createMetadataView(ctx);
+        UIComponent metadataFacet = viewRoot.getFacet(UIViewRoot.METADATA_FACET_NAME);
+
+        // Looking for a view parameter with the specified name
+        UIViewParameter viewParam = null;
+        for (UIComponent child : metadataFacet.getChildren()) {
+            if (child instanceof UIViewParameter) {
+                UIViewParameter tempViewParam = (UIViewParameter) child;
+                if (name.equals(tempViewParam.getName())) {
+                    viewParam = tempViewParam;
+                    break;
+                }
+            }
+        }
+
+        if (viewParam == null) {
+            throw new FacesException("Unknown parameter: '" + name + "' for view: " + viewId);
+        }
+
+        // Getting the value
+        String value = viewParam.getStringValue(ctx);
+        return includeParam(name, value);
+    }
+
+    public Page includeParam(String name, String value) {
+        Map<String, String> newParams = new LinkedHashMap<String, String>(params);
+        newParams.put(name, value);
+        return new Page(viewId, newParams, requiresLogin);
+    }
+
+    public String s() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(viewId);
+
+        String paramSeparator = "?";
+        for (Map.Entry<String, String> nameValue : params.entrySet()) {
+            sb.append(paramSeparator).append(nameValue.getKey()).append("=").append(nameValue.getValue());
+            paramSeparator = "&amp;";
+        }
+
+        return sb.toString();
+    }
+
+    public String getS() { return s(); }
+
+    public boolean isRequiresLogin() {
+        return requiresLogin;
+    }
+}

src/main/java/pl/softwaremill/cdiext/security/LoginBean.java

@@ -0,0 +1,12 @@
+package pl.softwaremill.cdiext.security;
+
+/**
+ * Should be implemented by the bean which controls the logged-in status of the user.
+ * @author Adam Warski (adam at warski dot org)
+ */
+public interface LoginBean {
+    /**
+     * @return True iff a user is currently logged in.
+     */
+    boolean isLoggedIn();
+}

src/main/java/pl/softwaremill/cdiext/security/SecurityPhaseListener.java

@@ -0,0 +1,49 @@
+package pl.softwaremill.cdiext.security;
+
+import pl.softwaremill.cdiext.navigation.NavBase;
+import pl.softwaremill.cdiext.util.BeanInject;
+
+import javax.faces.context.FacesContext;
+import javax.faces.event.PhaseEvent;
+import javax.faces.event.PhaseId;
+import javax.faces.event.PhaseListener;
+import java.io.IOException;
+
+/**
+ * TODO: go back after a redirect to login
+ *
+ * TODO: secure the cache:
+ * //Forces caches to obtain a new copy of the page from the origin server
+response.setHeader("Cache-Control","no-cache");
+//Directs caches not to store the page under any circumstance
+response.setHeader("Cache-Control","no-store");
+//Causes the proxy cache to see the page as "stale"
+response.setDateHeader("Expires", 0);
+//HTTP 1.0 backward compatibility
+response.setHeader("Pragma","no-cache");  
+ * @author Adam Warski (adam at warski dot org)
+ */
+public class SecurityPhaseListener implements PhaseListener {
+    public void beforePhase(PhaseEvent event) {
+        NavBase nav = BeanInject.lookup(NavBase.class);
+        LoginBean login = BeanInject.lookup(LoginBean.class);
+
+        if (nav.lookup(event.getFacesContext().getViewRoot().getViewId()).isRequiresLogin() && !login.isLoggedIn()) {
+            FacesContext ctx = event.getFacesContext();
+            String url = ctx.getApplication().getViewHandler().getActionURL(ctx, nav.getLogin().s());
+            try {
+                ctx.getExternalContext().redirect(ctx.getExternalContext().encodeActionURL(url));
+            } catch (IOException e) {
+                throw new RuntimeException(e);
+            }
+            ctx.responseComplete();
+        }
+    }
+
+    public void afterPhase(PhaseEvent event) { }
+
+    @Override
+    public PhaseId getPhaseId() {
+        return PhaseId.RENDER_RESPONSE;
+    }
+}

src/main/resources/META-INF/faces-config.xml

@@ -7,6 +7,7 @@
       http://java.sun.com/xml/ns/javaee/web-facesconfig_2_0.xsd">
     <lifecycle>
         <phase-listener>pl.softwaremill.cdiext.transaction.TransactionPhaseListener</phase-listener>
+        <phase-listener>pl.softwaremill.util.SecurityPhaseListener</phase-listener>
     </lifecycle>
 
     <application>