Introduction 

A plugin that can efficiently export data from Oracle to be used as a source in Hydrator pipelines.  Oracle includes command line tools to export data  that can be utilized to perform this task.  

User Stories

• As a Hydrator User I want to export data from Oracle to be used in my hydrator Pipeline.
• As a Hydrator User I want a Oracle Export plugin that exports data efficiently using existing existing Oracle tools. 
• As a Hydrator User I want the export data capability of the Oracle plugin to be based on a sql query that I issue.  
• User should be able to specify credentials.
• Passwords should not be viewable in plain text from inside pipeline viewer or hydrator studio.  
• User should be able to specify Oracle Instance
• User should be able to specify location of EXP Utility.   
• User should be able to specify type of output.
• User should be able to specify location of output files.  
• User should know of connectivity errors, or malformed queries/output identifier.   

Example

Example for how the plugin should workUser wants to export the data from test table using filter on name='cask' i.e Select * from test where name='cask';

Plugin configurations:

"oracleServerHostname": "example.com",
"oracleServerPort": "22",
"oracleServerUsername": "oracle",
"oracleServerPassword": "oracle@123",
"dbUsername": "system",
"dbPassword": "cask",
"oracleHome": "/u01/app/oracle/product/11.2.0/xe",
"oracleSID": "cask",
"queryToExecute": "select * from test where name='cask';"
"pathToWriteFinalOutput" : "/tmp/data.csv"
"format" : "csv"

Implementation Tips

Design 

Design:

{
    "name": "OracleExportAction",
      "plugin": {
        "name": "OracleExportAction",
        "type": "action",
        "label": "OracleExportAction",
        "artifact": {
          "name": "core-plugins",
          "version": "1.4.0-SNAPSHOT",
          "scope": "SYSTEM"
      },
      "properties": {
          "oracleServerHostname": "example.com",
          "oracleServerPort": "22",
          "serverUsernameoracleServerUsername": "oracle",
          "serverPasswordoracleServerPassword": "oracle@123",
          "dbUsername": "system",
          "dbPassword": "cask",
          "oracleHome": "/u01/app/oracle/product/11.2.0/xe",
          "oracleSID": "cask",
          "queryToExecute": "select * from test where name='cask';"
          "paramFilePathpathToWriteFinalOutput" : "/parameterstmp/paramdata.parcsv"
       }   "format" : "csv"
      }
}

oracleServerHostname:HostHostname name of the remote DB machine where the data dump command is to be executed

oracleServerPort:Port of the remote DB machine to connect to. Defaults to 22

serverUsernameoracleServerUsername:UserUsername name used to connect to for remote DB host

serverPasswordoracleServerPassword:Password used to connect to for remote DB host

dbUsername:UserUsername name to connect to oracle DB

dbPassword:Password to connect to oracle DB

oracleHome:Path of the ORACLE_HOME

oracleSID:Oracle SIDparamFilePath

queryToExecute: FullQuery pathto ofbe theexecuted PARAMto fileexport.ParamQuery file should containhave the';' requiredat parameters to run data dump command. e.g If you want to export the data from test table using filter for name column" +
  "DIRECTORY = test_dir(This should be already configured and should have required access)\n" +
  "DUMPFILE = table.dmp(dump file name)\n" +
  "LOGFILE = table_lg.log\n" +
  "TABLES = test(tables on which data export needs to be done)\n" +
  "QUERY = test:\"WHERE name = 'cask'\"

the end.

pathToWriteFinalOutput: Path where output file to be exported

format: Format of the output file

Plugin would run below sequence of commands in one session:

1.export ORACLE_HOME and ORACLE_SID

2.create a script file(/tmp/test.sql) and add below content.We can take the path of the tmp file as a config from the user or use the home folder of the logged in user where program would always have the access.

set colsep ","
set linesize 10000
set newpage none
set wrap off
set heading off
spool on
select * from test;
spool off
exit

3.execute $oracleHome/bin/sqlplus -s $dbUsername/$dbPassword@$oracleSID  @/tmp/test.sql

4.Read the outstream and write into the specified output file on local.Before writing,multiline trailing spaces remover regex will be applied.

5.Since sqlplus spool generates trailing spaces before and after the column separators,sed command will be applied to remove the spaces.