CODEWITHSUNDEEP
grailsservicenulldatasource
pinei
pinei

Reputation: 2293

Grails datasource becoming null in Service

I am using Grails 2.2.1, and I have a custom dataSource injected into the service so that I can execute some SQL queries.

Upon first execution, there is a dataSource, but on each subsequent call, the reference to the dataSource has become null.

class ReportService {
  def dataSource_myds

  Object[] reportRecords(int a) {
    String query = "SELECT ..."

    Object[] resultSet;

    Sql sql = new Sql(dataSource_myds)
    // ^ Here the NullPointerException is thrown
    // But it always works at the first execution

    sql.eachRow(query, [a]) {
      ...
      resultSet += result
    }
    return resultSet
  }
}

class ReportController {
  ReportService reportService

  def report = {
     ...
     Object[] resultSet1 = reportService.reportRecords(1)
     ...
     Object[] resultSet2 = reportService.reportRecords(2)
     // ^ java.lang.NullPointerException : Must specify a non-null Connection
     ...
  }
}

Has anyone ever seen this before, and if so, how can I avoid this?

Here is my DataSource.groovy

environments {
  development {
    dataSource_myds {
      url = "jdbc:oracle:thin:@..."
      driverClassName = "oracle.jdbc.driver.OracleDriver"
      username = "..."
      password = "..."
    }
  }
}

Upvotes: 3

Views: 3490

Answers (4)

RN110
RN110

Reputation: 91

I had a similar issue and I got it fixed. Firstly, make sure your Service class is in the grails-app/services folder. Secondly, you need to make sure you get the object of the service class using the injection mechanism and not by using the constructor. I had my service class in the right folder but I was trying to create the instance of the service class as MyService.instance in my controller and having the issue of null dataSource/connection. Then I tried def myService in my controller instead of MyService.instance and it worked. Hope this helps. Thanks

Upvotes: 1

ETL
ETL

Reputation: 10001

James Kleeh's comment solved it for me - grails clean and then restart the app.

Upvotes: 1

pinei
pinei

Reputation: 2293

Solved avoiding 2 subsequent calls to the service. It seems the framework nulls the service connection after the first call from the controller.

Upvotes: 1

Anuj Aneja
Anuj Aneja

Reputation: 1344

Try, to use resources.groovy way as well. This will also give you option for environment basis datasource.

Explained well on the link given below:

Grails 2 multiple dynamic datasources in services

Thanks

Upvotes: 1

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