fix: fix base actions issue. (#280)

render/engine.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"html/template"
 	"io"
+	"reflect"
 	"regexp"
 
 	tpls "github.com/go-echarts/go-echarts/v2/templates"
@@ -86,12 +87,29 @@ func (r *chartRender) Render(w io.Writer) error {
 	return err
 }
 
+// isSet check if the field exist in the chart instance
+// Shamed copy from https://stackoverflow.com/questions/44675087/golang-template-variable-isset
+func isSet(name string, data interface{}) bool {
+	v := reflect.ValueOf(data)
+
+	if v.Kind() == reflect.Ptr {
+		v = v.Elem()
+	}
+
+	if v.Kind() != reflect.Struct {
+		return false
+	}
+
+	return v.FieldByName(name).IsValid()
+}
+
 // MustTemplate creates a new template with the given name and parsed contents.
 func MustTemplate(name string, contents []string) *template.Template {
 	tpl := template.Must(template.New(name).Parse(contents[0])).Funcs(template.FuncMap{
 		"safeJS": func(s interface{}) template.JS {
 			return template.JS(fmt.Sprint(s))
 		},
+		"isSet": isSet,
 	})
 
 	for _, cont := range contents[1:] {

templates/base.go

@@ -1,5 +1,7 @@
 package templates
 
+// We should check the BaseActions field before call the JSONNotEscapedAction since the BaseActions only exist in RectCharts
+
 var BaseTpl = `
 {{- define "base" }}
 <div class="container">
@@ -10,7 +12,9 @@ var BaseTpl = `
     "use strict";
     let goecharts_{{ .ChartID | safeJS }} = echarts.init(document.getElementById('{{ .ChartID | safeJS }}'), "{{ .Theme }}");
     let option_{{ .ChartID | safeJS }} = {{ .JSONNotEscaped | safeJS }};
+    {{ if isSet  "BaseActions" . }}
 	let action_{{ .ChartID | safeJS }} = {{ .JSONNotEscapedAction | safeJS }};
+    {{ end }}
     goecharts_{{ .ChartID | safeJS }}.setOption(option_{{ .ChartID | safeJS }});
  	goecharts_{{ .ChartID | safeJS }}.dispatchAction(action_{{ .ChartID | safeJS }});