add core services, add graph service, add component graph

graph.go

@@ -0,0 +1,140 @@
+// Copyright (c) 2024 Zeni Kim <zenik@smarteching.com>
+// Use of this source code is governed by MIT-style
+// license that can be found in the LICENSE file.
+
+package core
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"git.smarteching.com/zeni/go-chart/v2"
+	"github.com/julienschmidt/httprouter"
+)
+
+func Graph(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
+
+	// $_GET values
+
+	service := ps.ByName("graph")
+
+	if service != "" {
+
+		//serv := strings.TrimPrefix(service, "/")
+		serv := strings.Split(service, "/")
+
+		switch serv[1] {
+
+		case "graph":
+
+			kindg := serv[2]
+
+			if kindg != "" {
+
+				switch kindg {
+				// case graph pie
+				case "pie":
+
+					queryValues := r.URL.Query()
+					labels := strings.Split(queryValues.Get("l"), "|")
+					values := strings.Split(queryValues.Get("v"), "|")
+
+					qtyl := len(labels)
+					qtyv := len(values)
+
+					// cjeck qty and equal values from url
+					if qtyl < 2 {
+						fmt.Fprintf(w, "Missing captions in pie")
+						return
+					}
+					if qtyv != qtyl {
+						fmt.Fprintf(w, "Labels and values mismatch")
+						return
+					}
+
+					var cvalues []chart.Value
+					var row chart.Value
+					// fill values
+					for index, line := range labels {
+						valuefloat, _ := strconv.ParseFloat(values[index], 64)
+						row.Value = valuefloat
+						row.Label = line
+						cvalues = append(cvalues, row)
+					}
+
+					pie := chart.PieChart{
+						Width:  512,
+						Height: 512,
+						Values: cvalues,
+					}
+					w.Header().Set("Content-Type", "image/png")
+					err := pie.Render(chart.PNG, w)
+					if err != nil {
+						fmt.Printf("Error rendering pie chart: %v\n", err)
+					}
+
+				// case graph bar
+				case "bar":
+
+					queryValues := r.URL.Query()
+					labels := strings.Split(queryValues.Get("l"), "|")
+					values := strings.Split(queryValues.Get("v"), "|")
+
+					qtyl := len(labels)
+					qtyv := len(values)
+
+					// cjeck qty and equal values from url
+					if qtyl < 2 {
+						fmt.Fprintf(w, "Missing captions in pie")
+						return
+					}
+					if qtyv != qtyl {
+						fmt.Fprintf(w, "Labels and values mismatch")
+						return
+					}
+
+					var cvalues []chart.Value
+					var row chart.Value
+					// fill values
+					for index, line := range labels {
+						valuefloat, _ := strconv.ParseFloat(values[index], 64)
+						row.Value = valuefloat
+						row.Label = line
+						cvalues = append(cvalues, row)
+					}
+
+					bar := chart.BarChart{
+						Height:   512,
+						BarWidth: 50,
+						Bars:     cvalues,
+					}
+					w.Header().Set("Content-Type", "image/png")
+					err := bar.Render(chart.PNG, w)
+					if err != nil {
+						fmt.Printf("Error rendering pie chart: %v\n", err)
+					}
+
+				default:
+					fmt.Fprintf(w, "Unknown graph %s!\n", kindg)
+				}
+
+			} else {
+				fmt.Fprintf(w, "Kind graph not exists")
+			}
+			//
+
+		default:
+
+			fmt.Fprintf(w, "Unknown option in core service %s!\n", ps.ByName("serv"))
+
+		}
+		fmt.Fprintf(w, "Service %s!\n", serv)
+
+	} else {
+
+		fmt.Fprintf(w, "Unknown core service %s!\n", ps.ByName("graph"))
+	}
+
+}