RE: Dynamically Discovering DataSource

[Rafiq, Adnan]

Larry,

 

Using ThreadLocal just might solve my problem. This is what I am thinking:

 

1 - Extend the JndiDataSourceFactory class and override the getDataSource method

2 - Obtain the company id from ThreadLocal (assuming that its been set in the DaoImpl class)

3 - In the getDataSource method of my new factory class, lookup the datasource name based on the company id

4 - Return the looked-up datasource name (instead of the one defined in sql maps xml file)

 

However, I need to figure out the following:

1 - If extend the JndiDataSourceFactory class, how do I plug it into iBatis?

2 - What will be the best place to set the company id in ThreadLocal

    a) In the DaoImpl class constructor, or

    b) In each DaoImpl class method

 

Your help is really appreciated in this matter.

 

Thanks,

 

- Adnan

-----Original Message-----
From: Larry Meadors [mailto:[EMAIL PROTECTED]
Sent: Thursday, April 21, 2005 11:15 AM
To: ibatis-user-java@incubator.apache.org
Subject: Re: Dynamically Discovering DataSource

This is such an unusual case that IMO, the DataSourceFactory should not be changed to accommodate it.

You could probably use a ThreadLocal class to set the parameter, then in your datasource, examine it to decide the real datasource to use.

Larry

On 4/21/05, Rafiq, Adnan <[EMAIL PROTECTED]> wrote:

Larry,

 

Thanks for the suggestion.

 

I looked at the DataSourceFactory. The method getDataSource() does not take any parameters. The flow of our application is like this:

 

1 - Contact the system datasource and get a list of all companies and their associated datasource jndi names

2 - When the user logs in, we get its company id and using it as a key we find the corresponding datasource jndi name

3 - The company datasource jndi name is then returned and used for all connections.

 

What seems like a good solution is to extend the JNDIDataSourceFactory and overload the method getDataSource so that it can accept a company id as an argument: getDataSource(int companyId). Internally, we have a map of companyid (key) and datasource name (value).

 

However, what I can't figure out is where that method is actually called in iBatis.

 

Thanks,

 

- Adnan

-----Original Message-----
From: Larry Meadors [mailto:[EMAIL PROTECTED]]
Sent: Thursday, April 21, 2005 10:26 AM
To: ibatis-user-java@incubator.apache.org
Subject: Re: Dynamically Discovering DataSource

Roll your own javax.sql.DataSource (6 methods) and com.ibatis.sqlmap.engine.datasource.DataSourceFactory (2 methods).

Larry

On 4/21/05, Rafiq, Adnan <[EMAIL PROTECTED]> wrote:

I have a situation where we have an ASP-like environment. There is one system database and several customer-specific databases. Each customer database is mapped to a different datasource. In iBatis we have to hardcode the JNDI name for the datasource in the sql-map-confi.xml file. Is there anyway to make this dynamic? In other words, I want to query the customer datasource name (the names are stored in the system database) at run time based on the user id, and then use that name for getting my connections.

 

Any help is greatly appreciated.