Read Replica Support

[Flo4604]

It would be nice to have read replica support out of the box, by passing multiple sql.db's and saying whether they are the master / read replica

[stephenafamo]

Since every function/method asks for a bob.Executor this wouldn't really be Bob's responsibility. I assume it would be possible to create an *sql.DB that understands the primary/replica routing and use that.

I'm not sure how other implementations of something like this look like, can you share?

[Flo4604]

There is https://github.com/bxcodec/dbresolver

[stephenafamo]

Because Bob only needs a valid executor, you can use that package.

	connectionDB := dbresolver.New(...)
	defer connectionDB.Close()

	bobExecutor := bob.New(connectionDB)

Does this work for your use case?

[Flo4604]

The packages has its own types that should be based of sql.DB and its other types but still imeplements most if it itself to support the multiple connections.
So bob.New() doesn't like the type

T (type dbresolver.DB) does not satisfy bob.StdInterface (wrong type for method PrepareContext)
		have PrepareContext(context.Context, string) (dbresolver.Stmt, error)
		want PrepareContext(context.Context, string) (*sql.Stmt, error)

I will try to edit the dbresolver package so it satisfies sql.db so I can pass it to bob.NewDB()

[stephenafamo]

It seems you would have to write a wrapper for it, similar to the wrappers Bob has for the standard library types:

• *sql.DB
• *sql.Tx
• *sql.Conn

Take a look at the stdlib.go

[Flo4604]

thanks for the pointers i'll look into this