Define base error in batch.go for better error handling

[Aisoipheo]

What do you want to change?

Define and export ErrBatchAlreadyClosed error for better error-handling

var (
    ErrBatchAlreadyClosed = errors.New("batch already closed")
)

Allows for

errors.Is(err, generated_package.ErrBatchAlreadyClosed)

Instead of awkward

err.Error() == "batch already closed"

Pros:

• Go-way of error-handling source
• Helps to check if specific error occurred efficiently

Cons:

• None

What database engines need to be changed?

PostgreSQL

What programming language backends need to be changed?

Go

Suggested solution

#2147