Externalize error messages

Author: chartsboy

src/main/java/com/google/visualization/datasource/DataSourceHelper.java

@@ -18,6 +18,7 @@
 import com.google.visualization.datasource.base.DataSourceParameters;
 import com.google.visualization.datasource.base.InvalidQueryException;
 import com.google.visualization.datasource.base.LocaleUtil;
+import com.google.visualization.datasource.base.MessagesEnum;
 import com.google.visualization.datasource.base.OutputType;
 import com.google.visualization.datasource.base.ReasonType;
 import com.google.visualization.datasource.base.ResponseStatus;
@@ -361,26 +362,35 @@ public static String generateErrorResponse(ResponseStatus responseStatus,
 
   // -------------------------- Query helper methods ----------------------------------------------
 
+  /** @see #parseQuery(String, ULocale)*/
+  public static Query parseQuery(String queryString) throws InvalidQueryException {
+    return parseQuery(queryString, null);
+  }
+  
   /**
    * Parses a query string (e.g., 'select A,B pivot B') and creates a Query object.
    * Throws an exception if the query is invalid.
    *
    * @param queryString The query string.
+   * @param locale The user locale.
    *
    * @return The parsed query object.
    *
    * @throws InvalidQueryException If the query is invalid.
    */
-  public static Query parseQuery(String queryString) throws InvalidQueryException {
+  public static Query parseQuery(String queryString, ULocale userLocale) 
+      throws InvalidQueryException {
     QueryBuilder queryBuilder = QueryBuilder.getInstance();
-    Query query = queryBuilder.parseQuery(queryString);
+    Query query = queryBuilder.parseQuery(queryString, userLocale);
 
     return query;
   }
 
   /**
    * Applies the given <code>Query</code> on the given <code>DataTable</code> and returns the
    * resulting <code>DataTable</code>. This method may change the given DataTable.
+   * Error messages produced by this method will be localized according to the passed locale 
+   * unless the specified {@code DataTable} has a non null locale. 
    *
    * @param query The query object.
    * @param dataTable The data table on which to apply the query.
@@ -393,8 +403,10 @@ public static Query parseQuery(String queryString) throws InvalidQueryException
    */
   public static DataTable applyQuery(Query query, DataTable dataTable, ULocale locale)
       throws InvalidQueryException, DataSourceException {
+    dataTable.setLocaleForUserMessages(locale);
     validateQueryAgainstColumnStructure(query, dataTable);
     dataTable = QueryEngine.executeQuery(query, dataTable, locale);
+    dataTable.setLocaleForUserMessages(locale);
     return dataTable;
   }
 
@@ -443,8 +455,8 @@ public static void validateQueryAgainstColumnStructure(Query query, DataTable da
     Set<String> mentionedColumnIds = query.getAllColumnIds();
     for (String columnId : mentionedColumnIds) {
       if (!dataTable.containsColumn(columnId)) {
-        String messageToLogAndUser = "Column [" + columnId + "] does not"
-            + " exist in table.";
+        String messageToLogAndUser = MessagesEnum.NO_COLUMN.getMessageWithArgs(
+            dataTable.getLocaleForUserMessages(), columnId);
         log.error(messageToLogAndUser);
         throw new InvalidQueryException(messageToLogAndUser);
       }

src/main/java/com/google/visualization/datasource/base/ErrorMessages.java

@@ -41,7 +41,43 @@ public class ErrorMessages extends ListResourceBundle {
     {"TIMEOUT", "Request timeout"},
     {"ILLEGAL_FORMATTING_PATTERNS", "Illegal formatting patterns"},
     {"OTHER", "Could not complete request"},
-    {"SIGN_IN", "Sign in"}  
+    {"SIGN_IN", "Sign in"},  
+    // QUERY Errors
+    {"NO_COLUMN", "Column [{0}] does not exist in table."},
+    {"AVG_SUM_ONLY_NUMERIC",
+        "'Average' and 'sum' aggreagation functions can be applied only on numeric values."},
+    {"INVALID_AGG_TYPE", "Invalid aggregation type: {0}"},
+    // Parse
+    {"PARSE_ERROR", "Query parse error: {0}"},
+    {"CANNOT_BE_IN_GROUP_BY", "Column [{0}] cannot be in GROUP BY because it has an aggregation."},
+    {"CANNOT_BE_IN_PIVOT", "Column [{0}] cannot be in PIVOT because it has an aggregation."},
+    {"CANNOT_BE_IN_WHERE", "Column [{0}] cannot appear in WHERE because it has an aggregation."},
+    {"SELECT_WITH_AND_WITHOUT_AGG", 
+        "Column [{0}] cannot be selected both with and without aggregation in SELECT."},
+    {"COL_AGG_NOT_IN_SELECT", 
+        "Column [{0}] which is aggregated in SELECT, cannot appear in GROUP BY."},
+    {"CANNOT_GROUP_WITNOUT_AGG", "Cannot use GROUP BY when no aggregations are defined in SELECT."},
+    {"CANNOT_PIVOT_WITNOUT_AGG", "Cannot use PIVOT when no aggregations are defined in SELECT."},
+    {"AGG_IN_SELECT_NO_PIVOT",
+        "Column [{0}] which is aggregated in SELECT, cannot appear in PIVOT."},
+    {"FORMAT_COL_NOT_IN_SELECT",
+        "Column [{0}] which is referenced in FORMAT, is not part of SELECT clause."},
+    {"LABEL_COL_NOT_IN_SELECT",
+        "Column [{0}] which is referenced in LABEL, is not part of SELECT clause."},
+    {"ADD_COL_TO_GROUP_BY_OR_AGG",
+        "Column [{0}] should be added to GROUP BY, removed from SELECT, or aggregated in SELECT."},
+    {"AGG_IN_ORDER_NOT_IN_SELECT",
+        "Aggregation [{0}] found in ORDER BY but was not found in SELECT"},
+    {"NO_AGG_IN_ORDER_WHEN_PIVOT",
+        "Column [{0}] cannot be aggregated in ORDER BY when PIVOT is used."},
+    {"COL_IN_ORDER_MUST_BE_IN_SELECT",
+        "Column [{0}] which appears in ORDER BY, must be in SELECT as well, " +
+        "because SELECT contains aggregated columns."},
+    {"NO_COL_IN_GROUP_AND_PIVOT", "Column [{0}] cannot appear both in GROUP BY and in PIVOT."},
+    {"INVALID_OFFSET", "Invalid value for row offset: {0}"},
+    {"COLUMN_ONLY_ONCE", "Column [{0}] cannot appear more than once in {1}."}
+    
+    
   };
 
   /**

src/main/java/com/google/visualization/datasource/base/LocaleUtil.java

@@ -14,6 +14,7 @@
 
 package com.google.visualization.datasource.base;
 
+import com.ibm.icu.text.MessageFormat;
 import com.ibm.icu.util.ULocale;
 
 import java.util.Locale;
@@ -114,4 +115,27 @@ public static String getLocalizedMessageFromBundle(String bundleName, String key
     }
     return ResourceBundle.getBundle(bundleName, locale).getString(key);
   }
+  
+  /**
+   * Returns a localized message from the specified <code>ResourceBundle</code> for the given key
+   * with the given arguments inserted to the message in the specified locations.
+   * In case the locale is null, uses the default locale.
+   * If locale is null, the default <code>ResourceBundle</code> is used.
+   * 
+   *
+   * @param bundleName The name of the resource bundle.
+   * @param key The key of the requested string.
+   * @param args Arguments to place in the error message.
+   * @param locale The locale.
+   *
+   * @return A localized message from the bundle based on the given locale.
+   */
+  public static String getLocalizedMessageFromBundleWithArguments(String bundleName, String key,
+      String[] args, Locale locale) {
+    String rawMesage = getLocalizedMessageFromBundle(bundleName, key, locale);
+    if (args != null && args.length > 0) {
+      return MessageFormat.format(rawMesage, args);
+    }
+    return rawMesage;
+  }
 }

src/main/java/com/google/visualization/datasource/base/MessagesEnum.java

@@ -0,0 +1,238 @@
+// Copyright 2009 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.visualization.datasource.base;
+
+import com.google.common.collect.Maps;
+
+import com.ibm.icu.util.ULocale;
+
+import java.util.Locale;
+import java.util.Map;
+
+/**
+ * An enum for messages used in the DataSource library. Each element references a message
+ * in {@code ErrorMessages}. For example all the error messages produced in query parsing are
+ * listed here.
+ *
+ * @author Hillel M.
+ */
+public enum MessagesEnum {
+
+  /**
+   * Column in query is missing from the data table.
+   * @param column id.
+   */
+  NO_COLUMN,
+  
+  /**
+   * Average and sum aggregation can be applied only on numeric columns.
+   */
+  AVG_SUM_ONLY_NUMERIC,
+  
+  /**
+   * Invalid aggregation type.
+   * @param aggregation type.
+   */
+  INVALID_AGG_TYPE,
+  
+  /**
+   * An error when parsing the query.
+   * @param detailed message.
+   */
+  PARSE_ERROR,
+  
+  /**
+   * Column can not be in group by because it has an aggregation.
+   * @param column id 
+   */
+  CANNOT_BE_IN_GROUP_BY,
+  
+  /**
+   * Column can not be in pivot because it has an aggregation.
+   * @param column id 
+   */
+  CANNOT_BE_IN_PIVOT,
+  
+  /**
+   * Column can not be in where because it has an aggregation.
+   * @param column id 
+   */
+  CANNOT_BE_IN_WHERE,
+  
+  /**
+   * Column can not appear in select with and without aggregation.
+   * @param column id.
+   */
+  SELECT_WITH_AND_WITHOUT_AGG,
+  
+  /**
+   * Column which is aggregated in SELECT, cannot appear in GROUP BY.
+   * @param column id
+   */
+  COL_AGG_NOT_IN_SELECT,
+  
+  /**
+   * Cannot use GROUP BY when no aggregations are defined in SELECT. 
+   */
+  CANNOT_GROUP_WITNOUT_AGG,
+  
+  /**
+   * Cannot use PIVOT when no aggregations are defined in SELECT.
+   */
+  CANNOT_PIVOT_WITNOUT_AGG,
+  
+  /**
+   * Column which is aggregated in SELECT, cannot appear in PIVOT.
+   * @param column id
+   */
+  AGG_IN_SELECT_NO_PIVOT,
+  
+  /**
+   * Column which is referenced in FORMAT, is not part of SELECT clause.
+   * @param column id
+   */
+  FORMAT_COL_NOT_IN_SELECT,
+  
+  /**
+   * Column which is referenced in LABEL, is not part of SELECT clause.
+   * @param column id 
+   */
+  LABEL_COL_NOT_IN_SELECT,
+  
+  /**
+   * Column should be added to GROUP BY, removed from SELECT, or aggregated in SELECT.
+   * @param column id
+   */
+  ADD_COL_TO_GROUP_BY_OR_AGG,
+  
+  
+  /**
+   * Aggregation found in ORDER BY but was not found in SELECT.
+   * @param aggreation column
+   */
+   AGG_IN_ORDER_NOT_IN_SELECT,
+   
+   /**
+    * Column cannot be aggregated in ORDER BY when PIVOT is used.
+    * @param aggregation column
+    */
+   NO_AGG_IN_ORDER_WHEN_PIVOT,
+  
+  /**
+   * Column which appears in ORDER BY, must be in SELECT as well, because SELECT
+   * contains aggregated columns.
+   */
+   COL_IN_ORDER_MUST_BE_IN_SELECT,
+  
+  /**
+   * Column cannot appear both in GROUP BY and in PIVOT.
+   * @param column id 
+   */
+   NO_COL_IN_GROUP_AND_PIVOT,
+  
+  /**
+   * Invalid value for row offset.
+   * @param value
+   */
+   INVALID_OFFSET,
+   
+   /**
+    * Column cannot appear more than once.
+    * @param column id
+    * @param clause
+    */
+   COLUMN_ONLY_ONCE;
+   
+  /**
+   * A mapping from reason type to message.
+   */
+  private static final Map<MessagesEnum, String>
+      QUERY_ERROR_TO_MESSAGE = Maps.newEnumMap(MessagesEnum.class);
+
+  static {
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.NO_COLUMN,
+        "NO_COLUMN");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.AVG_SUM_ONLY_NUMERIC,
+        "AVG_SUM_ONLY_NUMERIC");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.INVALID_AGG_TYPE,
+        "INVALID_AGG_TYPE");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.PARSE_ERROR,
+        "PARSE_ERROR");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.CANNOT_BE_IN_GROUP_BY,
+        "CANNOT_BE_IN_GROUP_BY");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.CANNOT_BE_IN_PIVOT,
+        "CANNOT_BE_IN_PIVOT");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.CANNOT_BE_IN_WHERE,
+        "CANNOT_BE_IN_WHERE");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.SELECT_WITH_AND_WITHOUT_AGG,
+        "SELECT_WITH_AND_WITHOUT_AGG");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.COL_AGG_NOT_IN_SELECT,
+        "COL_AGG_NOT_IN_SELECT");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.CANNOT_GROUP_WITNOUT_AGG,
+        "CANNOT_GROUP_WITNOUT_AGG");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.CANNOT_PIVOT_WITNOUT_AGG,
+        "CANNOT_PIVOT_WITNOUT_AGG");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.AGG_IN_SELECT_NO_PIVOT,
+        "AGG_IN_SELECT_NO_PIVOT");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.FORMAT_COL_NOT_IN_SELECT,
+        "FORMAT_COL_NOT_IN_SELECT");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.LABEL_COL_NOT_IN_SELECT,
+        "LABEL_COL_NOT_IN_SELECT");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.ADD_COL_TO_GROUP_BY_OR_AGG,
+        "ADD_COL_TO_GROUP_BY_OR_AGG");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.AGG_IN_ORDER_NOT_IN_SELECT,
+        "AGG_IN_ORDER_NOT_IN_SELECT");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.NO_AGG_IN_ORDER_WHEN_PIVOT,
+        "NO_AGG_IN_ORDER_WHEN_PIVOT");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.COL_IN_ORDER_MUST_BE_IN_SELECT,
+        "COL_IN_ORDER_MUST_BE_IN_SELECT");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.NO_COL_IN_GROUP_AND_PIVOT,
+        "NO_COL_IN_GROUP_AND_PIVOT");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.INVALID_OFFSET,
+        "INVALID_OFFSET");
+    QUERY_ERROR_TO_MESSAGE.put(MessagesEnum.COLUMN_ONLY_ONCE,
+        "COLUMN_ONLY_ONCE");
+  }
+  
+
+  /**
+   * Returns a localized message for this reason type and locale.
+   *
+   * @param locale The locale.
+   * @param args An array of arguments.
+   *
+   * @return A localized message given a reason type and locale.
+   */
+  public String getMessageWithArgs(ULocale ulocale, String... args) {
+    Locale locale = ulocale != null ? ulocale.toLocale() : null;
+    return LocaleUtil.getLocalizedMessageFromBundleWithArguments(
+        "com.google.visualization.datasource.base.ErrorMessages", QUERY_ERROR_TO_MESSAGE.get(this),
+        args, locale);
+  }
+  
+  /**
+   * Returns a localized message for this reason type and locale.
+   *
+   * @param locale The locale.
+   *
+   * @return A localized message given a reason type and locale.
+   */
+  public String getMessage(ULocale ulocale) {
+    Locale locale = ulocale != null ? ulocale.toLocale() : null;
+    return LocaleUtil.getLocalizedMessageFromBundle(
+        "com.google.visualization.datasource.base.ErrorMessages", QUERY_ERROR_TO_MESSAGE.get(this), 
+        locale);
+  }
+}