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How to Read data from Jdbc and write to bigquery using Apache Beam Python Sdk

I am trying to write a Pipeline which will Read Data From JDBC(oracle,mssql) , do something and write to bigquery.

I am Struggling in the ReadFromJdbc steps where it was not able to convert it correct schema type.

My Code:

import typing

import apache_beam as beam
from apache_beam import coders
from apache_beam.io.gcp.spanner import ReadFromSpanner
from input.base_source_processor import BaseSourceProcessor
from apache_beam.io.jdbc import ReadFromJdbc


class Row(typing.NamedTuple):
   COUNTRY_ID: str
   COUNTRY_NAME: str
   inc_col: str


class RdbmsProcessor(BaseSourceProcessor, abc.ABC):
   def __init__(self, task):
       self.task = task

   def expand(self, p_input):
       row = typing.NamedTuple('row', [('COUNTRY_ID', str), ('COUNTRY_NAME', str), ('inc_col', str)])
       coders.registry.register_coder(Row, coders.RowCoder)

       data = (p_input
               | "Read from rdbms" >> ReadFromJdbc(
                   driver_class_name=self.task['rdbms_props']['driver_class_name'],
                   jdbc_url=self.task['rdbms_props']['jdbc_url'],
                   username=self.task['rdbms_props']['username'],
                   password=self.task['rdbms_props']['password'],
                   table_name='"dm-demo".COUNTRIES',
                   classpath=['/home/abhinav_jha_datametica_com/python_df/odbc_jars/ojdbc8.jar']
               )
               )

       data | beam.combiners.Count.Globally() | beam.Map(print)

       data | beam.Map(print)

       return data

My data has three columns two of which are Varchar and one is timestamp. Here is how my data looks like

Error which i am facing while running from dataflow as well as direct runner

ValueError: Failed to decode schema due to an issue with Field proto:
name: "COUNTRY_ID"
type {
  logical_type {
    urn: "beam:logical_type:javasdk:v1"
    payload: "202SNAPPY00000000010000000100000223525010360U2543550005sr00=org.apache.beam.sdk.io.jdbc.LogicalTypes$VariableLengthStringr<273'6u341257020001I00tmaxt3514xr008242X0020JdbcL31i270246376361367203_313a020004L0010argumentt0022Ljava/lang/Object;L0014ar 0124334t00.Lorg/t31600/013164/sdk/schemas/S051024$Field01034;L0010base0114Dq00~0003L00nidentifier6r00t35730;xpsr00210121100.01211<.Integer223422402443672012078%07$05valuexr002031(hNumber2062542253513224340213020000xp00000007sr006N(01r26224.AutoV01N00_t27404_F21274h9304m364S243227P020010L0025collectionEle!/353230413l9\10t000216"0100L312$;L00nmapKey35S1414map052273524,10metadatat0017)25234util/Map!g(nullablet0023t35!>8/Boolean;L00trowt34310t00$2122430001T(typeNamet00-21220000$0125401/20;xr00,nu01t210Y'3413PLl[3573103%266010114sr0036%3330134204.C5|Ds$EmptyMapY624205Z33434732005300s2202r364,315 r200325234372356020001ZQ230p00p~r00+21223400213140000r0130220000xr001605225!Z20.Enumr340535$pt0005INT32sA35100t0130601t002201051024p~0107\25t0006STRINGt0007VARCHAR00000007"
    representation {
      atomic_type: STRING
    }
    argument_type {
      atomic_type: INT32
    }
    argument {
      atomic_value {
        int32: 7
      }
    }
  }
}

Any Help regarding this would be greatly appreciated.

Answer

JdbcIO appears to rely on Java-only logical types, so Python cannot deserialize them. This is tracked in https://issues.apache.org/jira/browse/BEAM-13717