Create datatables.go

datatables.go

@@ -0,0 +1,170 @@
+// This package parse a http request from datatables (jQuery plugin) to a friendly structure
+// More details in https://github.com/saulortega/datatables
+// import "github.com/saulortega/datatables"
+
+package datatables
+
+import (
+	"errors"
+	"net/http"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+type Column struct {
+	Data        string
+	Name        string
+	Index       int
+	Orderable   bool
+	Searchable  bool
+	SearchValue string
+	SearchRegex bool
+}
+
+type Order struct {
+	Column Column
+	Dir    string
+}
+
+type Filter struct {
+	Draw        int
+	Start       int
+	Length      int
+	Order       []Order
+	Columns     []Column
+	SearchValue string
+	SearchRegex bool
+}
+
+func Parse(r *http.Request) (Filter, error) {
+	return parse(r)
+}
+
+func MustParse(r *http.Request) Filter {
+	f, err := parse(r)
+	if err != nil {
+		panic(err)
+	}
+	return f
+}
+
+func parse(r *http.Request) (Filter, error) {
+	var E error
+	var F = Filter{
+		Order:   []Order{},
+		Columns: []Column{},
+	}
+
+	var errores = []string{}
+	var mapColsTmp = make(map[int]map[string]string)
+	var mapOrdsTmp = make(map[int]map[string]string)
+
+	for ll, v := range r.Form {
+		if regexp.MustCompile(`^columns\[`).MatchString(ll) {
+			a := regexp.MustCompile(`^columns\[([0-9]+)\]\[`).ReplaceAllString(ll, "$1-")
+			a = regexp.MustCompile(`search\]\[(value|regex)`).ReplaceAllString(a, "search$1")
+			a = regexp.MustCompile(`\]$`).ReplaceAllString(a, "")
+			p := strings.Split(a, "-")
+			i, er := strconv.Atoi(p[0])
+			if er != nil {
+				errores = append(errores, er.Error())
+				continue
+			}
+
+			if _, ok := mapColsTmp[i]; !ok {
+				mapColsTmp[i] = make(map[string]string)
+			}
+			mapColsTmp[i][p[1]] = v[0]
+		} else if regexp.MustCompile(`^order\[`).MatchString(ll) {
+			a := regexp.MustCompile(`^order\[([0-9]+)\]\[`).ReplaceAllString(ll, "$1-")
+			a = regexp.MustCompile(`\]$`).ReplaceAllString(a, "")
+			p := strings.Split(a, "-")
+			i, er := strconv.Atoi(p[0])
+			if er != nil {
+				errores = append(errores, er.Error())
+				continue
+			}
+
+			if _, ok := mapOrdsTmp[i]; !ok {
+				mapOrdsTmp[i] = make(map[string]string)
+			}
+			mapOrdsTmp[i][p[1]] = v[0]
+		} else if ll == "search[value]" {
+			F.SearchValue = strings.TrimSpace(v[0])
+		} else if ll == "search[regex]" {
+			F.SearchRegex, E = strconv.ParseBool(v[0])
+			if E != nil {
+				errores = append(errores, E.Error())
+			}
+		} else if ll == "start" {
+			F.Start, E = strconv.Atoi(v[0])
+			if E != nil {
+				errores = append(errores, E.Error())
+			}
+		} else if ll == "length" {
+			F.Length, E = strconv.Atoi(v[0])
+			if E != nil {
+				errores = append(errores, E.Error())
+			}
+		} else if ll == "draw" {
+			F.Draw, E = strconv.Atoi(v[0])
+			if E != nil {
+				errores = append(errores, E.Error())
+			}
+		}
+	}
+
+	for i := 0; i < len(mapColsTmp); i++ {
+		c := Column{Index: i}
+		c.Data = strings.TrimSpace(mapColsTmp[i]["data"])
+		c.Name = strings.TrimSpace(mapColsTmp[i]["name"])
+		c.Orderable, E = strconv.ParseBool(mapColsTmp[i]["orderable"])
+		if E != nil {
+			errores = append(errores, E.Error())
+		}
+		c.Searchable, E = strconv.ParseBool(mapColsTmp[i]["searchable"])
+		if E != nil {
+			errores = append(errores, E.Error())
+		}
+		c.SearchValue = strings.TrimSpace(mapColsTmp[i]["searchvalue"])
+		c.SearchRegex, E = strconv.ParseBool(mapColsTmp[i]["searchregex"])
+		if E != nil {
+			errores = append(errores, E.Error())
+		}
+		F.Columns = append(F.Columns, c)
+	}
+
+	for i := 0; i < len(mapOrdsTmp); i++ {
+		dir := strings.ToUpper(mapOrdsTmp[i]["dir"])
+		ic, er := strconv.Atoi(mapOrdsTmp[i]["column"])
+		if er != nil || (dir != "ASC" && dir != "DESC") {
+			if er != nil {
+				errores = append(errores, er.Error())
+			} else {
+				errores = append(errores, "dir invalid: «"+dir+"»")
+			}
+			continue
+		}
+
+		o := Order{Dir: dir}
+		for _, c := range F.Columns {
+			if c.Index == ic {
+				o.Column = c
+				break
+			}
+		}
+		if o.Column == (Column{}) {
+			errores = append(errores, "column with index "+strconv.Itoa(ic)+" not found")
+			continue
+		}
+
+		F.Order = append(F.Order, o)
+	}
+
+	if len(errores) > 0 {
+		E = errors.New(strings.Join(errores, "; "))
+	}
+
+	return F, E
+}