/*

* SPDX-License-Identifier: Apache-2.0

* Copyright 2018-2019 The Feast Authors

*

* 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

*

* https://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 feast.core.util;

import com.google.common.base.Strings;

import com.google.gson.Gson;

import com.google.gson.reflect.TypeToken;

import java.lang.reflect.Type;

import java.util.*;

import java.util.Map.Entry;

public class TypeConversion {

private static Gson gson = new Gson();

/**

* Convert a java data object to protobuf Timestamp object

*

* @param ts timestamp

* @return protobuf.Timestamp object of the given timestamp

*/

public static com.google.protobuf.Timestamp convertTimestamp(Date ts) {

return com.google.protobuf.Timestamp.newBuilder().setSeconds(ts.getTime() / 1000).build();

}

/**

* Convert a string of comma-separated strings to list of strings

*

* @param tags comma separated tags

* @return list of tags

*/

public static List<String> convertTagStringToList(String tags) {

if (tags == null || tags.isEmpty()) {

return Collections.emptyList();

}

return Arrays.asList(tags.split(","));

}

/**

* Unmarshals a given json string to map

*

* @param jsonString valid json formatted string

* @return map of keys to values in json

*/

public static Map<String, String> convertJsonStringToMap(String jsonString) {

if (jsonString == null || jsonString.equals("") || jsonString.equals("{}")) {

return Collections.emptyMap();

}

Type stringMapType = new TypeToken<Map<String, String>>() {}.getType();

return gson.fromJson(jsonString, stringMapType);

}

/**

* Marshals a given map into its corresponding json string

*

* @param map

* @return json string corresponding to given map

*/

public static String convertMapToJsonString(Map<String, String> map) {

return gson.toJson(map);

}

/**

* Convert a map of key value pairs to a array of java arguments in format --key=value

*

* @param map

* @return array of string arguments

*/

public static String[] convertMapToArgs(Map<String, String> map) {

List<String> args = new ArrayList<>();

for (Entry<String, String> arg : map.entrySet()) {

args.add(Strings.lenientFormat("--%s=%s", arg.getKey(), arg.getValue()));

}

return args.toArray(new String[] {});

}

}