Post submission only supports iso-8859-1 encoding about sql-jdbc

[dai-chen]

@PengtaoNing Thanks for reporting the issue! Could you provide some sample data and use case where you met the problem in our JDBC driver?

[ningpengtao-coder]

@PengtaoNing Thanks for reporting the issue! Could you provide some sample data and use case where you met the problem in our JDBC driver?

POST _bulk
{"create":{"_index":"sql_data","_id":1}}
{"name":"中文1"}
{"create":{"_index":"sql_data","_id":2}}
{"name":"中文2"}
{"create":{"_index":"sql_data","_id":3}}
{"name":"中文3"}
{"create":{"_index":"sql_data","_id":4}}
{"name":"中文4"}
{"create":{"_index":"sql_data","_id":5}}
{"name":"中文5"}

correct

kibana:
POST _opendistro/_sql
{
"query": "SELECT * FROM sql_data where name = '中文1'"
}

correct

curl:
curl -XPOST "http://localhost:9200/_opendistro/_sql" -H 'Content-Type: application/json' -d'{ "query": "SELECT * FROM sql_data where name = "中文1""}'

incorrect

jdbc:
Connection connection = DriverManager.getConnection(jdbcElasticsearchURL);

Statement statement = connection.createStatement();

ResultSet resultSet = statement.executeQuery("SELECT * FROM sql_data where name = '中文1'");

default charset: ISO-8859-1

The JDBC SQL statement is incorrect because the SQL statement is encoded to：

SELECT * FROM sql_data where name = '????1'

[dai-chen]

@PengtaoNing Thanks for the info! Will try to reproduce from my side.

[penghuo]

The issue has been fixed with #68. Feel free to reopen it.