Java 类名:com.alibaba.alink.operator.stream.dataproc.format.CsvToJsonStreamOp
Python 类名:CsvToJsonStreamOp

功能介绍

将数据格式从 Csv 转成 Json

参数说明

| 名称 | 中文名称 | 描述 | 类型 | 是否必须? | 取值范围 | 默认值 | | —- | —- | —- | —- | —- | —- | —- |

| csvCol | CSV列名 | CSV列的列名 | String | ✓ | 所选列类型为 [STRING] | |

| jsonCol | JSON列名 | JSON列的列名 | String | ✓ | | |

| schemaStr | Schema | Schema。格式为”colname coltype[, colname2, coltype2[, …]]”,例如”f0 string, f1 bigint, f2 double” | String | ✓ | | |

| csvFieldDelimiter | 字段分隔符 | 字段分隔符 | String | | | “,” |

| handleInvalid | 解析异常处理策略 | 解析异常处理策略,可选为ERROR(抛出异常)或者SKIP(输出NULL) | String | | “ERROR”, “SKIP” | “ERROR” |

| quoteChar | 引号字符 | 引号字符 | Character | | | “”” |

| reservedCols | 算法保留列名 | 算法保留列 | String[] | | | null |

代码示例

Python 代码

  1. from pyalink.alink import *
  2. import pandas as pd
  3. useLocalEnv(1)
  4. df = pd.DataFrame([
  5. ['1', '{"f0":"1.0","f1":"2.0"}', '$3$0:1.0 1:2.0', 'f0:1.0,f1:2.0', '1.0,2.0', 1.0, 2.0],
  6. ['2', '{"f0":"4.0","f1":"8.0"}', '$3$0:4.0 1:8.0', 'f0:4.0,f1:8.0', '4.0,8.0', 4.0, 8.0]])
  7. data = StreamOperator.fromDataframe(df, schemaStr="row string, json string, vec string, kv string, csv string, f0 double, f1 double")
  8. op = CsvToJsonStreamOp()\
  9. .setCsvCol("csv")\
  10. .setSchemaStr("f0 double, f1 double")\
  11. .setReservedCols(["row"])\
  12. .setJsonCol("json")\
  13. .linkFrom(data)
  14. op.print()
  15. StreamOperator.execute()

Java 代码

  1. import org.apache.flink.types.Row;
  2. import com.alibaba.alink.operator.stream.StreamOperator;
  3. import com.alibaba.alink.operator.stream.dataproc.format.CsvToJsonStreamOp;
  4. import com.alibaba.alink.operator.stream.source.MemSourceStreamOp;
  5. import org.junit.Test;
  6. import java.util.Arrays;
  7. import java.util.List;
  8. public class CsvToJsonStreamOpTest {
  9. @Test
  10. public void testCsvToJsonStreamOp() throws Exception {
  11. List <Row> df = Arrays.asList(
  12. Row.of("1", "{\"f0\":\"1.0\",\"f1\":\"2.0\"}", "$3$0:1.0 1:2.0", "f0:1.0,f1:2.0", "1.0,2.0", 1.0, 2.0),
  13. Row.of("2", "{\"f0\":\"4.0\",\"f1\":\"8.0\"}", "$3$0:4.0 1:8.0", "f0:4.0,f1:8.0", "4.0,8.0", 4.0, 8.0)
  14. );
  15. StreamOperator <?> data = new MemSourceStreamOp(df,
  16. "row string, json string, vec string, kv string, csv string, f0 double, f1 double");
  17. StreamOperator <?> op = new CsvToJsonStreamOp()
  18. .setCsvCol("csv")
  19. .setSchemaStr("f0 double, f1 double")
  20. .setReservedCols("row")
  21. .setJsonCol("json")
  22. .linkFrom(data);
  23. op.print();
  24. StreamOperator.execute();
  25. }
  26. }

运行结果

| row | json | | —- | —- |

| 1 | {“f0”:”1.0”,”f1”:”2.0”} |

| 2 | {“f0”:”4.0”,”f1”:”8.0”} |