feat(validation): 添加表单验证功能并集成到名称处理器

- 新增基于结构体标签的验证器实现
- 实现必填和最小值验证规则- 在名称处理器中集成验证逻辑
- 添加验证错误页面模板- 注册默认验证服务
- 创建名称输入表单模板
- 为 NewName 结构体添加验证标签

32-platform/platform/placeholder/name_form.html

@@ -0,0 +1,15 @@
+{{ layout "layout.html" }}
+
+<form method="post" action="{{ . }}">
+    <div style="padding:5px">
+        <label for="name">Name:</label>
+        <input id="name" name="name"/>
+    </div>
+    <div style="padding:5px">
+        <label for="insertatstart">Insert at Front:</label>
+        <input id="insertatstart" name="insertatstart" type="checkbox" value="true"/>
+    </div>
+    <div style="padding:5px">
+        <input type="submit" value="Submit"/>
+    </div>
+</form>

32-platform/platform/placeholder/name_handler.go

@@ -5,6 +5,7 @@ import (
 	"platform/http/actionresults"
 	"platform/http/handing"
 	"platform/logging"
+	"platform/validation"
 )
 
 var names = []string{"Alice", "Bob", "charlie", "Dora"}
@@ -12,10 +13,11 @@ var names = []string{"Alice", "Bob", "charlie", "Dora"}
 type NameHandler struct {
 	logging.Logger
 	handing.URLGenerator
+	validation.Validator
 }
 
 type NewName struct {
-	Name          string
+	Name          string `validation:"required,min:3"`
 	InsertAtStart bool
 }
 
@@ -35,8 +37,16 @@ func (n NameHandler) GetNames() actionresults.ActionResult {
 	return actionresults.NewTemplateAction("simple_message.html", names)
 }
 
+func (n NameHandler) GetFOrm() actionresults.ActionResult {
+	postUrl, _ := n.URLGenerator.GenerateUrl(NameHandler.PostName)
+	return actionresults.NewTemplateAction("name_form.html", postUrl)
+}
+
 func (n NameHandler) PostName(new NewName) actionresults.ActionResult {
 	n.Logger.Debugf("PostName method invoked with argument: %v", new)
+	if ok, errs := n.Validator.Validate(&new); !ok {
+		return actionresults.NewTemplateAction("validation_errors.html", errs)
+	}
 	if new.InsertAtStart {
 		names = append([]string{new.Name}, names...)
 	} else {

32-platform/platform/placeholder/validation_errors.html

@@ -0,0 +1,8 @@
+{{ layout "layout.html" }}
+
+<h3>Validation Errors</h3>
+<ul>
+    {{ range . }}
+    <li>{{ .FieldName }}:{{ .Error }}</li>
+    {{ end }}
+</ul>

32-platform/platform/services/services_default.go

@@ -4,6 +4,7 @@ import (
 	"platform/config"
 	"platform/logging"
 	"platform/templates"
+	"platform/validation"
 )
 
 func RegisterDefaultService() {
@@ -39,4 +40,12 @@ func RegisterDefaultService() {
 	if err != nil {
 		panic(err)
 	}
+
+	// 注册验证服务
+	err = AddSingleton(func() validation.Validator {
+		return validation.NewDefaultValidator()
+	})
+	if err != nil {
+		panic(err)
+	}
 }

32-platform/platform/validation/tag_validator.go

@@ -0,0 +1,62 @@
+package validation
+
+import (
+	"reflect"
+	"strings"
+)
+
+func NewDefaultValidator() Validator {
+	return NewValidator(DefaultValidators())
+}
+
+func NewValidator(validators map[string]ValidatorFunc) Validator {
+	return &TagValidator{
+		validators: validators,
+	}
+}
+
+type TagValidator struct {
+	validators map[string]ValidatorFunc
+}
+
+func (tv *TagValidator) Validate(data interface{}) (ok bool, errs []ValidatorError) {
+	errs = []ValidatorError{}
+
+	dataVal := reflect.ValueOf(data)
+	if dataVal.Kind() == reflect.Ptr {
+		dataVal = dataVal.Elem()
+	}
+	if dataVal.Kind() != reflect.Struct {
+		panic("Only structs can be validated")
+	}
+	for i := 0; i < dataVal.NumField(); i++ {
+		fieldType := dataVal.Type().Field(i)
+		validationTag, found := fieldType.Tag.Lookup("validate")
+		if !found {
+			continue
+		}
+		for _, v := range strings.Split(validationTag, ",") {
+			var name, arg string = "", ""
+			if strings.Contains(v, ":") {
+				nameAndArgs := strings.SplitN(v, ":", 2)
+				name = nameAndArgs[0]
+				arg = nameAndArgs[1]
+			} else {
+				name = v
+			}
+			if validator, ok := tv.validators[name]; ok {
+				valid, err := validator(fieldType.Name, dataVal.Field(i).Interface(), arg)
+				if !valid {
+					errs = append(errs, ValidatorError{
+						FieldName: fieldType.Name,
+						Error:     err,
+					})
+				} else {
+					panic("Unknow validator:" + name)
+				}
+			}
+		}
+	}
+	ok = len(errs) == 0
+	return
+}

32-platform/platform/validation/validator.go

@@ -0,0 +1,56 @@
+package validation
+
+import (
+	"fmt"
+	"strconv"
+)
+
+type Validator interface {
+	Validate(data interface{}) (ok bool, errs []ValidatorError)
+}
+
+// ValidatorError 验证错误
+type ValidatorError struct {
+	FieldName string
+	Error     error
+}
+type ValidatorFunc func(fieldName string, value interface{}, arg string) (bool, error)
+
+func DefaultValidators() map[string]ValidatorFunc {
+	return map[string]ValidatorFunc{
+		"required": required,
+		"min":      minValue,
+	}
+}
+
+func required(fieldName string, value interface{}, arg string) (valid bool, err error) {
+	if str, ok := value.(string); ok {
+		valid = str != ""
+		err = fmt.Errorf("字段 %v 不能为空", fieldName)
+		return
+	} else {
+		err = fmt.Errorf("字段 %v 必须为字符串", fieldName)
+	}
+	return
+}
+
+func minValue(fieldName string, value interface{}, arg string) (valid bool, err error) {
+	minVal, err := strconv.Atoi(arg)
+	if err != nil {
+		err = fmt.Errorf("字段 %v 的配置参数 %v 必须为数字", fieldName, arg)
+		return
+	}
+	if iVal, iValOk := value.(int); iValOk {
+		valid = iVal >= minVal
+		err = fmt.Errorf("字段 %v 的值不能小于 %v", fieldName, minVal)
+	} else if fVal, fValOk := value.(float64); fValOk {
+		valid = fVal >= float64(minVal)
+		err = fmt.Errorf("字段 %v 的值不能小于 %v", fieldName, minVal)
+	} else if sVal, sValOk := value.(string); sValOk {
+		err = fmt.Errorf("字段 %v 的值长度不能小于 %v", fieldName, minVal)
+		valid = len(sVal) >= minVal
+	} else {
+		err = fmt.Errorf("字段 %v 的值类型必须为int,float,string", fieldName)
+	}
+	return
+}