protected String getUserDn()

in gateway-provider-security-shiro/src/main/java/org/apache/knox/gateway/shirorealm/KnoxLdapRealm.java [676:743]
60 lines of code
13 McCabe index (conditional complexity)

    protected String getUserDn( final String principal ) throws IllegalArgumentException, IllegalStateException {
      String userDn;
      Matcher matchedPrincipal = matchPrincipal( principal );
      String userSearchBase = getUserSearchBase();
      String userSearchAttributeName = getUserSearchAttributeName();

      // If not searching use the userDnTemplate and return.
      if ( ( userSearchBase == null || userSearchBase.isEmpty() ) ||
          ( userSearchAttributeName == null &&
              userSearchFilter == null &&
              !"object".equalsIgnoreCase( userSearchScope ) ) ) {
        userDn = expandTemplate( userDnTemplate, matchedPrincipal );
        LOG.computedUserDn( userDn, principal );
        return userDn;
      }

      // Create the searchBase and searchFilter from config.
      String searchBase = expandTemplate( getUserSearchBase(), matchedPrincipal );
      String searchFilter;
      if ( userSearchFilter == null ) {
        if ( userSearchAttributeName == null ) {
          searchFilter = String.format( Locale.ROOT, "(objectclass=%1$s)", getUserObjectClass() );
        } else {
          searchFilter = String.format( Locale.ROOT,
              "(&(objectclass=%1$s)(%2$s=%3$s))",
              getUserObjectClass(),
              userSearchAttributeName,
              expandTemplate( getUserSearchAttributeTemplate(), matchedPrincipal ) );
        }
      } else {
        searchFilter = expandTemplate( userSearchFilter, matchedPrincipal );
      }
      SearchControls searchControls = getUserSearchControls();

      // Search for userDn and return.
      LdapContext systemLdapCtx = null;
      NamingEnumeration<SearchResult> searchResultEnum = null;
      try {
        systemLdapCtx = getContextFactory().getSystemLdapContext();
        LOG.searchBaseFilterScope(searchBase, searchFilter, userSearchScope);
        searchResultEnum = systemLdapCtx.search( searchBase, searchFilter, searchControls );
        // SearchResults contains all the entries in search scope
        if (searchResultEnum.hasMore()) {
          SearchResult searchResult = searchResultEnum.next();
          userDn = searchResult.getNameInNamespace();
          LOG.searchedAndFoundUserDn(userDn, principal);
          return userDn;
        } else {
          throw new IllegalArgumentException("Illegal principal name: " + principal);
        }
      } catch (AuthenticationException e) {
        LOG.failedToGetSystemLdapConnection(e);
        throw new IllegalArgumentException("Illegal principal name: " + principal, e);
      } catch (NamingException e) {
        throw new IllegalArgumentException("Hit NamingException", e);
      } finally {
        try {
          if (searchResultEnum != null) {
            searchResultEnum.close();
          }
        } catch (NamingException e) {
          // Ignore exception on close.
        }
        finally {
          LdapUtils.closeContext(systemLdapCtx);
        }
      }
    }