美文网首页Go语言
Golang Echo数据绑定中time.Time类型绑定失败

Golang Echo数据绑定中time.Time类型绑定失败

作者: 承诺一时的华丽 | 来源:发表于2018-08-03 17:06 被阅读2次

    1、首先看官方绑定,time.Time将绑定失败

    func(c echo.Context) (err error) {
      u := new(User)
      if err = c.Bind(u); err != nil {
        return
      }
      return c.JSON(http.StatusOK, u)
    }
    

    2、自定义绑定

    加入Struct类型判断:


    image.png

    直接添加选项

        case reflect.Struct:
            //时间类型
            var t time.Time
            var err error
            val = strings.Replace(val, " 00:00:00", "", -1)
            
            if IsValidDate(val) {         //判断日期格式
                t, err = ParseDate(val)
                if err == nil {
                    structField.Set(reflect.ValueOf(t))
                }
            } else if IsValidTime(val) {         //判断日期时间格式
                t, err = ParseTime(val)
                if err == nil {
                    structField.Set(reflect.ValueOf(t))
                }
            }
            break
    

    完整版bind.go

    package handle
    
    import (
        "reflect"
        "strconv"
        "strings"
        "github.com/labstack/echo"
        "net/http"
        "encoding/json"
        "fmt"
        "errors"
        "encoding/xml" 
        "time"
    )
    
    type CustomBinder struct{}
    
    // Bind implements the `Binder#Bind` function.
    func (b *CustomBinder) Bind(i interface{}, c echo.Context) (err error) {
        req := c.Request()
        if req.ContentLength == 0 {
            if req.Method == echo.GET || req.Method == echo.DELETE {
                if err = b.bindData(i, c.QueryParams(), "query"); err != nil {
                    return echo.NewHTTPError(http.StatusBadRequest, err.Error())
                }
                return
            }
            return echo.NewHTTPError(http.StatusBadRequest, "Request body can't be empty")
        }
        ctype := req.Header.Get(echo.HeaderContentType)
        switch {
        case strings.HasPrefix(ctype, echo.MIMEApplicationJSON):
            if err = json.NewDecoder(req.Body).Decode(i); err != nil {
                if ute, ok := err.(*json.UnmarshalTypeError); ok {
                    return echo.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Unmarshal type error: expected=%v, got=%v, field=%v, offset=%v", ute.Type, ute.Value, ute.Field, ute.Offset))
                } else if se, ok := err.(*json.SyntaxError); ok {
                    return echo.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Syntax error: offset=%v, error=%v", se.Offset, se.Error()))
                } else {
                    return echo.NewHTTPError(http.StatusBadRequest, err.Error())
                }
            }
        case strings.HasPrefix(ctype, echo.MIMEApplicationXML), strings.HasPrefix(ctype, echo.MIMETextXML):
            if err = xml.NewDecoder(req.Body).Decode(i); err != nil {
                if ute, ok := err.(*xml.UnsupportedTypeError); ok {
                    return echo.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Unsupported type error: type=%v, error=%v", ute.Type, ute.Error()))
                } else if se, ok := err.(*xml.SyntaxError); ok {
                    return echo.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Syntax error: line=%v, error=%v", se.Line, se.Error()))
                } else {
                    return echo.NewHTTPError(http.StatusBadRequest, err.Error())
                }
            }
        case strings.HasPrefix(ctype, echo.MIMEApplicationForm), strings.HasPrefix(ctype, echo.MIMEMultipartForm):
            params, err := c.FormParams()
            if err != nil {
                return echo.NewHTTPError(http.StatusBadRequest, err.Error())
            }
            if err = b.bindData(i, params, "form"); err != nil {
                return echo.NewHTTPError(http.StatusBadRequest, err.Error())
            }
        default:
            return echo.ErrUnsupportedMediaType
        }
        return
    }
    
    func (b *CustomBinder) bindData(ptr interface{}, data map[string][]string, tag string) error {
        typ := reflect.TypeOf(ptr).Elem()
        val := reflect.ValueOf(ptr).Elem()
    
        if typ.Kind() != reflect.Struct {
            return errors.New("binding element must be a struct")
        }
    
        for i := 0; i < typ.NumField(); i++ {
            typeField := typ.Field(i)
            structField := val.Field(i)
            if !structField.CanSet() {
                continue
            }
            structFieldKind := structField.Kind()
            inputFieldName := typeField.Tag.Get(tag)
    
            if inputFieldName == "" {
                inputFieldName = typeField.Name
                // If tag is nil, we inspect if the field is a struct.
                if _, ok := bindUnmarshaler(structField); !ok && structFieldKind == reflect.Struct {
                    err := b.bindData(structField.Addr().Interface(), data, tag)
                    if err != nil {
                        return err
                    }
                    continue
                }
            }
    
            inputValue, exists := data[inputFieldName]
            if !exists {
                // Go json.Unmarshal supports case insensitive binding.  However the
                // url params are bound case sensitive which is inconsistent.  To
                // fix this we must check all of the map values in a
                // case-insensitive search.
                inputFieldName = strings.ToLower(inputFieldName)
                for k, v := range data {
                    if strings.ToLower(k) == inputFieldName {
                        inputValue = v
                        exists = true
                        break
                    }
                }
            }
    
            if !exists {
                continue
            }
    
            // Call this first, in case we're dealing with an alias to an array type
            if ok, err := unmarshalField(typeField.Type.Kind(), inputValue[0], structField); ok {
                if err != nil {
                    return err
                }
                continue
            }
    
            numElems := len(inputValue)
            if structFieldKind == reflect.Slice && numElems > 0 {
                sliceOf := structField.Type().Elem().Kind()
                slice := reflect.MakeSlice(structField.Type(), numElems, numElems)
                for j := 0; j < numElems; j++ {
                    if err := setWithProperType(sliceOf, inputValue[j], slice.Index(j)); err != nil {
                        return err
                    }
                }
                val.Field(i).Set(slice)
            } else {
                if err := setWithProperType(typeField.Type.Kind(), inputValue[0], structField); err != nil {
                    return err
                }
            }
        }
        return nil
    }
    
    func setWithProperType(valueKind reflect.Kind, val string, structField reflect.Value) error {
        // But also call it here, in case we're dealing with an array of BindUnmarshalers
        if ok, err := unmarshalField(valueKind, val, structField); ok {
            return err
        }
    
        switch valueKind {
        case reflect.Ptr:
            return setWithProperType(structField.Elem().Kind(), val, structField.Elem())
        case reflect.Int:
            return setIntField(val, 0, structField)
        case reflect.Int8:
            return setIntField(val, 8, structField)
        case reflect.Int16:
            return setIntField(val, 16, structField)
        case reflect.Int32:
            return setIntField(val, 32, structField)
        case reflect.Int64:
            return setIntField(val, 64, structField)
        case reflect.Uint:
            return setUintField(val, 0, structField)
        case reflect.Uint8:
            return setUintField(val, 8, structField)
        case reflect.Uint16:
            return setUintField(val, 16, structField)
        case reflect.Uint32:
            return setUintField(val, 32, structField)
        case reflect.Uint64:
            return setUintField(val, 64, structField)
        case reflect.Bool:
            return setBoolField(val, structField)
        case reflect.Float32:
            return setFloatField(val, 32, structField)
        case reflect.Float64:
            return setFloatField(val, 64, structField)
        case reflect.String:
            structField.SetString(val)
        case reflect.Struct:
            //时间类型
            var t time.Time
            var err error
            val = strings.Replace(val, " 00:00:00", "", -1)
            if IsValidDate(val) {
                t, err = ParseDate(val)
                if err == nil {
                    structField.Set(reflect.ValueOf(t))
                }
            } else if IsValidTime(val) {
                t, err = ParseTime(val)
                if err == nil {
                    structField.Set(reflect.ValueOf(t))
                }
            }
            break
        default:
            return errors.New("unknown type")
        }
        return nil
    }
    
    func unmarshalField(valueKind reflect.Kind, val string, field reflect.Value) (bool, error) {
        switch valueKind {
        case reflect.Ptr:
            return unmarshalFieldPtr(val, field)
        default:
            return unmarshalFieldNonPtr(val, field)
        }
    }
    
    // bindUnmarshaler attempts to unmarshal a reflect.Value into a BindUnmarshaler
    func bindUnmarshaler(field reflect.Value) (echo.BindUnmarshaler, bool) {
        ptr := reflect.New(field.Type())
        if ptr.CanInterface() {
            iface := ptr.Interface()
            if unmarshaler, ok := iface.(echo.BindUnmarshaler); ok {
                return unmarshaler, ok
            }
        }
        return nil, false
    }
    
    func unmarshalFieldNonPtr(value string, field reflect.Value) (bool, error) {
        if unmarshaler, ok := bindUnmarshaler(field); ok {
            err := unmarshaler.UnmarshalParam(value)
            field.Set(reflect.ValueOf(unmarshaler).Elem())
            return true, err
        }
        return false, nil
    }
    
    func unmarshalFieldPtr(value string, field reflect.Value) (bool, error) {
        if field.IsNil() {
            // Initialize the pointer to a nil value
            field.Set(reflect.New(field.Type().Elem()))
        }
        return unmarshalFieldNonPtr(value, field.Elem())
    }
    
    func setIntField(value string, bitSize int, field reflect.Value) error {
        if value == "" {
            value = "0"
        }
        intVal, err := strconv.ParseInt(value, 10, bitSize)
        if err == nil {
            field.SetInt(intVal)
        }
        return err
    }
    
    func setUintField(value string, bitSize int, field reflect.Value) error {
        if value == "" {
            value = "0"
        }
        uintVal, err := strconv.ParseUint(value, 10, bitSize)
        if err == nil {
            field.SetUint(uintVal)
        }
        return err
    }
    
    func setBoolField(value string, field reflect.Value) error {
        if value == "" {
            value = "false"
        }
        boolVal, err := strconv.ParseBool(value)
        if err == nil {
            field.SetBool(boolVal)
        }
        return err
    }
    
    func setFloatField(value string, bitSize int, field reflect.Value) error {
        if value == "" {
            value = "0.0"
        }
        floatVal, err := strconv.ParseFloat(value, bitSize)
        if err == nil {
            field.SetFloat(floatVal)
        }
        return err
    }
    
    
    func ParseTime(date string) (time.Time, error) {
        date = strings.Replace(date, "/", "-", -1)
        date = strings.Replace(date, ".", "-", -1)
        return time.Parse("2006-01-02 15:04:05", date)
    }
    
    func ParseDate(date string) (time.Time, error) {
        date = strings.Replace(date, "/", "-", -1)
        date = strings.Replace(date, ".", "-", -1)
        return time.Parse("2006-01-02", date)
    }
    
    
    
    func IsValidTime(s string) bool {
        _, err := time.Parse("2006-01-02 15:04:05", s)
        if err != nil {
            return false
        }
        return true
    }
    
    func IsValidDate(s string) bool { 
        _, err := time.Parse("2006-01-02", s)
        if err != nil {
            return false
        }
        return true
    }
    

    使用示例:

    if err := new(CustomBinder).Bind(user, c); err != nil {
            ...
    }
    

    相关文章

      网友评论

        本文标题:Golang Echo数据绑定中time.Time类型绑定失败

        本文链接:https://www.haomeiwen.com/subject/aztyvftx.html