moltin/gomo

package gomo

import "github.com/moltin/gomo/core"

// NextPage advances the supplied Meta to the next page by returning a new
// offset and limit
func NextPage(meta core.Meta) (int, int) {
    offset := meta.Page.Offset + meta.Page.Limit
    return offset, meta.Page.Limit
}

// MorePages returns true is the meta suggests there are more results
// available
func MorePages(meta core.Meta) bool {
    return meta.Page.Current < meta.Page.Total
}

// Iterate calls the function with a RequestResource that should be
// passed to a Get() request. The function is called for each page
// of size limit. If the function returns an error at any point
// the iteration stops and the error is returned.
func Iterate(limit int, f func(RequestResource) error) error {
    meta := core.Meta{
        Page: core.MetaPage{
            Offset:  0,
            Limit:   limit,
            Current: 0,
            Total:   1,
        },
    }
    offset := 0
    for MorePages(meta) {
        err := f(func(w *wrapper) {
            w.apply(
                Paginate(offset, limit),
                Meta(&meta),
            )
        })
        if err != nil {
            return err
        }
        offset, limit = NextPage(meta)
    }
    return nil
}