SOLR-179 -- Initalization collects any errors and displays them rather then continuing. this feature is configurable in solrconfig.xml

git-svn-id: https://svn.apache.org/repos/asf/lucene/solr/trunk@532912 13f79535-47bb-0310-9956-ffa450edef68

example/solr/conf/solrconfig.xml

@@ -17,6 +17,14 @@
 -->
 
 <config>
+  <!-- Set this to 'false' if you want solr to continue working after it has 
+       encountered an severe configuration error.  In a production environment, 
+       you may want solr to keep working even if one handler is mis-configured.
+
+       You may also set this to false using by setting the system property:
+         -Dsolr.abortOnConfigurationError=false
+     -->
+  <abortOnConfigurationError>${solr.abortOnConfigurationError:true}</abortOnConfigurationError>
 
   <!-- Used to specify an alternate directory to hold all index data
        other than the default ./data under the Solr home.

src/java/org/apache/solr/core/RequestHandlers.java

@@ -18,7 +18,6 @@
 package org.apache.solr.core;
 
 import java.net.URL;
-import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
@@ -145,7 +144,7 @@ final class RequestHandlers {
           names.put( name, args );
         } 
         catch (Exception e) {
-          // TODO: SOLR-179
+          SolrConfig.severeErrors.add( e );
           SolrException.logOnce(log,null,e);
         }
       }
@@ -156,7 +155,7 @@ final class RequestHandlers {
           handlers.get( reg.getKey() ).init( reg.getValue() );
         }
         catch( Exception e ) {
-          // TODO: SOLR-179
+          SolrConfig.severeErrors.add( e );
           SolrException.logOnce(log,null,e);
         }
       }
@@ -307,3 +306,4 @@ final class RequestHandlers {
 
 
 
+

src/java/org/apache/solr/core/SolrConfig.java

@@ -25,6 +25,8 @@ import org.xml.sax.SAXException;
 
 import javax.xml.parsers.ParserConfigurationException;
 
+import java.util.Collection;
+import java.util.HashSet;
 import java.util.StringTokenizer;
 import java.io.IOException;
 import java.io.InputStream;
@@ -47,6 +49,11 @@ public class SolrConfig {
    */
   public static Config config;
 
+  /**
+   * Singleton keeping track of configuration errors
+   */
+  public static final Collection<Throwable> severeErrors = new HashSet<Throwable>();
+
   /**
    * (Re)loads the static configation information from the specified file.
    *
@@ -79,6 +86,7 @@ public class SolrConfig {
     try {
       initConfig(DEFAULT_CONF_FILE);
     } catch (Exception ee) {
+      severeErrors.add( ee );
       throw new RuntimeException("Error in " + DEFAULT_CONF_FILE, ee);
     }
   }

src/java/org/apache/solr/core/SolrCore.java

@@ -728,6 +728,7 @@ public final class SolrCore {
         writer.init(DOMUtil.childNodesToNamedList(elm));
         responseWriters.put(name, writer);
       } catch (Exception ex) {
+        SolrConfig.severeErrors.add( ex );
         SolrException.logOnce(log,null, ex);
         // if a writer can't be created, skip it and continue
       }
@@ -773,3 +774,4 @@ public final class SolrCore {
   }
 }
 
+

src/java/org/apache/solr/schema/IndexSchema.java

@@ -24,6 +24,7 @@ import org.apache.lucene.document.Fieldable;
 import org.apache.lucene.search.DefaultSimilarity;
 import org.apache.lucene.search.Similarity;
 import org.apache.lucene.queryParser.QueryParser;
+import org.apache.solr.core.SolrConfig;
 import org.apache.solr.core.SolrException;
 import org.apache.solr.core.Config;
 import org.apache.solr.analysis.TokenFilterFactory;
@@ -467,9 +468,11 @@ public final class IndexSchema {
       dynamicCopyFields = (DynamicCopy[])dCopies.toArray(new DynamicCopy[dCopies.size()]);
 
     } catch (SolrException e) {
+      SolrConfig.severeErrors.add( e );
       throw e;
     } catch(Exception e) {
       // unexpected exception...
+      SolrConfig.severeErrors.add( e );
       throw new SolrException(1,"Schema Parsing Failed",e,false);
     }
 
@@ -820,3 +823,4 @@ public final class IndexSchema {
 
 }
 
+

src/webapp/src/org/apache/solr/servlet/SolrDispatchFilter.java

@@ -51,18 +51,52 @@ public class SolrDispatchFilter implements Filter
   protected SolrRequestParsers parsers;
   protected boolean handleSelect = false;
   protected String pathPrefix = null; // strip this from the begging of a path
+  protected String abortErrorMessage = null;
   
   public void init(FilterConfig config) throws ServletException 
   {
     log.info("SolrDispatchFilter.init()");
-        
-    // web.xml configuration
-    this.pathPrefix = config.getInitParameter( "path-prefix" );
-    this.handleSelect = "true".equals( config.getInitParameter( "handle-select" ) );
     
-    log.info("user.dir=" + System.getProperty("user.dir"));
-    core = SolrCore.getSolrCore();
-    parsers = new SolrRequestParsers( core, SolrConfig.config );
+    try {
+      // web.xml configuration
+      this.pathPrefix = config.getInitParameter( "path-prefix" );
+      this.handleSelect = "true".equals( config.getInitParameter( "handle-select" ) );
+      
+      log.info("user.dir=" + System.getProperty("user.dir"));
+      core = SolrCore.getSolrCore();
+      parsers = new SolrRequestParsers( core, SolrConfig.config );
+    }
+    catch( Throwable t ) {
+      // catch this so our filter still works
+      SolrConfig.severeErrors.add( t );
+      SolrCore.log( t );
+    }
+    
+    // Optionally abort if we found a sever error
+    boolean abortOnConfigurationError = SolrConfig.config.getBool("abortOnConfigurationError",true);
+    if( abortOnConfigurationError && SolrConfig.severeErrors.size() > 0 ) {
+      StringWriter sw = new StringWriter();
+      PrintWriter out = new PrintWriter( sw );
+      out.println( "Severe errors in solr configuration.\n" );
+      out.println( "Check your log files for more detailed infomation on what may be wrong.\n" );
+      out.println( "If you want solr to continue after configuration errors, change: \n");
+      out.println( " <abortOnConfigurationError>false</abortOnConfigurationError>\n" );
+      out.println( "in solrconfig.xml\n" );
+      
+      for( Throwable t : SolrConfig.severeErrors ) {
+        out.println( "-------------------------------------------------------------" );
+        t.printStackTrace( out );
+      }
+      out.flush();
+      
+      // Servlet containers behave slightly differntly if you throw an exception durring 
+      // initalization.  Resin will display that error for every page, jetty prints it in
+      // the logs, but continues normally.  (We will see a 404 rather then the real error)
+      // rather then leave the behavior undefined, lets cache the error and spit it out 
+      // for every request.
+      abortErrorMessage = sw.toString();
+      //throw new ServletException( abortErrorMessage );
+    }
     
     log.info("SolrDispatchFilter.init() done");
   }
@@ -73,6 +107,11 @@ public class SolrDispatchFilter implements Filter
   
   public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException 
   {
+    if( abortErrorMessage != null ) {
+      ((HttpServletResponse)response).sendError( 500, abortErrorMessage );
+      return;
+    }
+    
     if( request instanceof HttpServletRequest) {
       SolrQueryRequest solrReq = null;
       HttpServletRequest req = (HttpServletRequest)request;