Initial commit.

utils/pagination.go

@@ -0,0 +1,37 @@
+package utils
+
+type OffsetPaginationError struct {
+	Page     int
+	Pages    int
+	NextPage int
+	LastPage int
+}
+
+func (p *OffsetPaginationError) Error() string {
+	return "Not an error, just for offsetbased pagination."
+}
+
+func NewOffsetPaginationError(page int, pages int) error {
+	var nextPage int
+	if page+1 <= pages {
+		nextPage = page + 1
+	} else {
+		nextPage = -1
+	}
+
+	return &OffsetPaginationError{Page: page, Pages: pages, NextPage: nextPage, LastPage: page - 1}
+}
+
+type KeysetPaginationError struct {
+	Key         int
+	NextKey     int
+	PreviousKey int
+}
+
+func (p *KeysetPaginationError) Error() string {
+	return "Not an error, just for Keysetbased pagination."
+}
+
+func NewKeysetPaginationError(key int, next int, previous int) error {
+	return &KeysetPaginationError{Key: key, NextKey: next, PreviousKey: previous}
+}