fix(ListParams): address zero-indexing error in ListParams

Merge pull request #101 from qri-io/fix/list_params

api/handlers/history.go

@@ -36,7 +36,6 @@ func (h *HistoryHandlers) LogHandler(w http.ResponseWriter, r *http.Request) {
 }
 
 func (h *HistoryHandlers) logHandler(w http.ResponseWriter, r *http.Request) {
- p := util.PageFromRequest(r)
  params := &core.LogParams{
  ListParams: core.ListParamsFromRequest(r),
  Path: datastore.NewKey(r.URL.Path[len("/history/"):]),

core/params.go

@@ -14,39 +14,40 @@ type GetParams struct {
  Hash string
 }
 
+// ListParams is the general input for any sort of Paginated Request
+// ListParams define limits & offsets, not pages & page sizes.
+// TODO - rename this to PageParams.
 type ListParams struct {
  OrderBy string
  Limit int
  Offset int
 }
 
-// ListParamsFromRequest extracts ListParams from an http.Request pointer
-func ListParamsFromRequest(r *http.Request) ListParams {
- lp := &ListParams{}
- var pageIndex int
- if i, err := util.ReqParamInt("pageSize", r); err == nil {
- lp.Limit = i
+// NewListParams creates a ListParams from page & pagesize, pages are 1-indexed
+// (the first element is 1, not 0), NewListParams performs the conversion
+func NewListParams(orderBy string, page, pageSize int) ListParams {
+ if page < 1 {
+ page = 1
  }
- if i, err := util.ReqParamInt("page", r); err == nil {
- pageIndex = i
+ if pageSize <= 0 {
+ pageSize = DEFAULT_PAGE_SIZE
  }
- if pageIndex < 0 {
- pageIndex = 0
+ return ListParams{
+ Limit: pageSize,
+ Offset: (page - 1) * pageSize,
  }
- lp.Clean()
- lp.Offset = pageIndex * lp.Limit
- // lp.OrderBy defaults to empty string
- return *lp
-
 }
 
-func (lp *ListParams) Clean() {
- if lp.Limit <= 0 {
- lp.Limit = DEFAULT_PAGE_SIZE
+// ListParamsFromRequest extracts ListParams from an http.Request pointer
+func ListParamsFromRequest(r *http.Request) ListParams {
+ var page, pageSize int
+ if i, err := util.ReqParamInt("page", r); err == nil {
+ page = i
  }
- if lp.Offset < 0 {
- lp.Offset = 0
+ if i, err := util.ReqParamInt("pageSize", r); err == nil {
+ pageSize = i
  }
+ return NewListParams(r.FormValue("orderBy"), page, pageSize)
 }
 
 // Page converts a ListParams struct to a util.Page struct