basic common app packages

request/pager.go

@@ -0,0 +1,90 @@
+// Copyright 2024 Patial Tech (Ankit Patial).
+// All rights reserved.
+
+package request
+
+import (
+	"net/http"
+	"strconv"
+	"strings"
+
+	"code.patial.tech/go/appcore/ptr"
+)
+
+type Pager struct {
+	Search      string
+	OrderBy     *string `json:"orderBy"`
+	OrderAsc    *bool   `json:"orderAsc"`
+	Page        int     `json:"page"`
+	Size        int     `json:"size"`
+	Total       int     `json:"total"`
+	TotalNeeded bool    `json:"-"`
+}
+
+func (i *Pager) HasSearch() bool {
+	if i == nil {
+		return false
+	}
+
+	return strings.TrimSpace(i.Search) != ""
+}
+
+func (i *Pager) Offset() int {
+	if i == nil {
+		return 0
+	}
+
+	return (i.Page - 1) * i.Limit()
+}
+
+func (i *Pager) Limit() int {
+	if i == nil || ptr.GetNumber(&i.Size) < 1 {
+		return 20
+	}
+
+	return i.Size
+}
+
+// GetPager info from request's query parameters
+func GetPager(r *http.Request) Pager {
+	p := Pager{
+		Page:     1,
+		Size:     20,
+		OrderAsc: ptr.Bool(true),
+	}
+
+	if v := r.URL.Query().Get("q"); v != "" {
+		p.Search = strings.TrimSpace(v)
+	}
+
+	if v := r.URL.Query().Get("pg"); v != "" {
+		if vv, err := strconv.Atoi(v); err == nil {
+			p.Page = int(vv)
+		}
+	}
+
+	if v := r.URL.Query().Get("pg_s"); v != "" {
+		if vv, err := strconv.Atoi(v); err == nil {
+			p.Size = int(vv)
+		}
+	}
+
+	if v := r.URL.Query().Get("pg_ob"); v != "" {
+		p.OrderBy = &v
+	}
+
+	if v := r.URL.Query().Get("pg_o"); v != "" {
+		switch strings.ToLower(v) {
+		case "asc":
+			p.OrderAsc = ptr.Bool(true)
+		case "desc":
+			p.OrderAsc = ptr.Bool(false)
+		}
+	}
+
+	if v := r.URL.Query().Get("pg_t"); v == "n" {
+		p.TotalNeeded = true
+	}
+
+	return p
+}