Fixes #10567: Infinite \"rudder is loading\" page if rudder-init didn…

…'t run

rudder-web/src/main/scala/bootstrap/liftweb/LiftInitContextListener.scala

@@ -89,23 +89,35 @@ class LiftInitContextListener extends ContextLoaderListener {
     initSpringAuthentication()
 
     val ms = System.currentTimeMillis()
+
     /*
-     * translate exception to UnavailableException
      *
-     * Note that that won't work for most exception thrown in RudderConfig, due to
-     * current arch: RudderConfig init all object in its constructor, and that will
-     * throw a java.lang.ExceptionInInitializerError (which can't be catched here,
-     * because it happens out of our scope, before init).
-     * None the less, that error will also stop jetty for that context, which is
-     * what we want in the end (it will be not so nice, thought)
+     * If any excpetion reach that point in init, we want to stop
+     * the application server.
+     * The "normal" way to handle that would have been to raise an
+     * UnavailableException, and so the web server would have then
+     * unloaded Rudder and responded with "error 503" to queries.
+     * But we are proxying Rudder with Apache and serving a "please
+     * wait, loading" page on that case.
+     * And in all case, an error in init almost always need a restart of Rudder.
+     *
+     * We can't simply "System.exit(1)", because it brokes everything.
+     * We can't simply throws an other exception, because for most of them,
+     * Jetty will mark the service unavailable (and so 503 and infinite "please
+     * wait" screen).
+     * So we need to make the JVM throw an IllegalStateException, which for some
+     * (totally unknown) reason make jetty unload the context and return 404 for
+     * queries on it (which we are correctly handling in Apache).
+     *
      */
 
     try {
       RudderConfig.init
     } catch {
-      case ex if(!ex.isInstanceOf[UnavailableException]) =>
-        ApplicationLogger.error("Fatal error during boot", ex)
-        throw new UnavailableException("An unrecoverable error occured during boot")
+      case ex =>
+        ApplicationLogger.error("Fatal error during boot, Rudder will stop now", ex)
+        //make the JVM throw the exception
+        ThrowIllegalAccessException.referenceMe
     }
 
     //init Spring

rudder-web/src/main/scala/bootstrap/liftweb/ThrowIllegalAccessException.java

@@ -0,0 +1,71 @@
+/*
+*************************************************************************************
+* Copyright 2017 Normation SAS
+*************************************************************************************
+*
+* This file is part of Rudder.
+*
+* Rudder is free software: you can redistribute it and/or modify
+* it under the terms of the GNU General Public License as published by
+* the Free Software Foundation, either version 3 of the License, or
+* (at your option) any later version.
+*
+* In accordance with the terms of section 7 (7. Additional Terms.) of
+* the GNU General Public License version 3, the copyright holders add
+* the following Additional permissions:
+* Notwithstanding to the terms of section 5 (5. Conveying Modified Source
+* Versions) and 6 (6. Conveying Non-Source Forms.) of the GNU General
+* Public License version 3, when you create a Related Module, this
+* Related Module is not considered as a part of the work and may be
+* distributed under the license agreement of your choice.
+* A "Related Module" means a set of sources files including their
+* documentation that, without modification of the Source Code, enables
+* supplementary functions or services in addition to those offered by
+* the Software.
+*
+* Rudder is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with Rudder.  If not, see <http://www.gnu.org/licenses/>.
+
+*
+*************************************************************************************
+*/
+package bootstrap.liftweb;
+
+/*
+ * This class must not be referenced but for throwing an IllegalStateException.
+ *
+ * It must be in Java to be able to use a static initializer and throw an
+ * IllegalArgumentException, which seems to be the only exception that make jetty
+ * unload the service WITHOUT making it returns 503 for it.
+ */
+public class ThrowIllegalAccessException {
+
+  /*
+   * Ah. Javac is somehow smart and look to see if the static initializer doesn't
+   * obviously fails. So we need to fool it (not very hard).
+   */
+  private static boolean foolCompiler(boolean choice) {
+    if(choice) {
+      throw new RuntimeException("An unrecoverable error happened during boot");
+    } else {
+      return choice;
+    }
+  }
+
+  /*
+   * Actually throws our exception.
+   */
+  static {
+    foolCompiler(true);
+  }
+
+  /*
+   * Something to reference to make the object be initialize.
+   */
+  public static int referenceMe = 42;
+}

rudder-web/src/main/scala/bootstrap/liftweb/checks/CheckDIT.scala

@@ -97,7 +97,7 @@ class CheckDIT(
           FAIL { "There is some required entries missing in the LDAP directory: %s".format(
             list.map {
               case (Failure(m,_,_), dn) => "%s (error message: %s)".format(dn.toString, m)
-              case (Empty,dn) => "%s (no error message)".format(dn.toString)
+              case (Empty,dn) => dn.toString
               case _ => "" //strange...
             }.mkString(" | ")
           )}
@@ -130,7 +130,7 @@ class CheckDIT(
           FAIL { "There is some required entries missing in the LDAP directory: %s".format(
             list.map {
               case (Failure(m,_,_), dn) => "%s (error message: %s)".format(dn.toString, m)
-              case (Empty,dn) => "%s (no error message)".format(dn.toString)
+              case (Empty,dn) => dn.toString
               case _ => "" //strange...
             }.mkString(" | ")
           )}