better LDAP query error reporting

Author: Vladimir Kotal

plugins/src/main/java/opengrok/auth/plugin/LdapUserPlugin.java

@@ -166,8 +166,8 @@ public void fillSession(HttpServletRequest req, User user) {
             if ((res = getLdapProvider().lookupLdapContent(dn, expandedFilter,
                     attributes.toArray(new String[0]))) == null) {
                 LOGGER.log(Level.WARNING, "failed to get LDAP attributes ''{2}'' for user {0} " +
-                                "with filter ''{1}''",
-                        new Object[]{user, expandedFilter, attributes});
+                                "with filter ''{1}'' from LDAP provider {3}",
+                        new Object[]{user, expandedFilter, attributes, getLdapProvider()});
                 return;
             }
 

plugins/src/main/java/opengrok/auth/plugin/ldap/LdapFacade.java

@@ -176,6 +176,8 @@ public LdapFacade(Configuration cfg) {
         setInterval(cfg.getInterval());
         setSearchBase(cfg.getSearchBase());
         setWebHooks(cfg.getWebHooks());
+
+        // Anti-pattern: do some non trivial stuff in the constructor.
         prepareSearchControls(cfg.getSearchTimeout(), cfg.getCountLimit());
         prepareServers();
     }
@@ -425,7 +427,8 @@ private <T> T processResult(SearchResult result, AttributeMapper<T> mapper) thro
     }
 
     public String toString() {
-        return String.join(",",
-                getServers().stream().map(LdapServer::getUrl).collect(Collectors.toList()));
+        return "{servers=" + String.join(",",
+                getServers().stream().map(LdapServer::getUrl).collect(Collectors.toList())) +
+                ", searchBase=" + getSearchBase() + "}";
     }
 }

plugins/src/test/java/opengrok/auth/plugin/LdapFacadeTest.java

@@ -7,6 +7,8 @@
 
 import javax.naming.directory.SearchControls;
 
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 
 import static org.junit.Assert.assertEquals;
@@ -36,4 +38,17 @@ public void testConnectTimeoutInheritance() {
         LdapFacade facade = new LdapFacade(config);
         assertTrue(facade.getServers().stream().anyMatch(s -> s.getConnectTimeout() == timeoutValue));
     }
+
+    @Test
+    public void testToString() {
+        Configuration config = new Configuration();
+        config.setServers(Arrays.asList(new LdapServer("http://foo.foo"),
+                new LdapServer("http://bar.bar")));
+        config.setSearchBase("dc=foo,dc=com");
+        int timeoutValue = 42;
+        config.setConnectTimeout(timeoutValue);
+        LdapFacade facade = new LdapFacade(config);
+        assertEquals("{servers=http://foo.foo,http://bar.bar, searchBase=dc=foo,dc=com}",
+                facade.toString());
+    }
 }