Validation in GO "ozzo-validation"

I'm a beginner in GO :) just try to create simple crud throw it using gin and plugin called ozzo-validation

My code:

package models

import (
    validation "github.com/go-ozzo/ozzo-validation"
    "gorm.io/gorm"
)

type Post struct {
    gorm.Model
    Name string `gorm:"type:varchar(255);"`
    Desc string `gorm:"type:varchar(500);"`
}

type PostData struct {
    Name string `json:"name"`
    Desc string `json:"desc"`
}

func (p PostData) Validate() error {
    return validation.ValidateStruct(&p,
        validation.Field(&p.Name, validation.Required, validation.Length(5, 20)),
        validation.Field(&p.Desc, validation.Required),
    )
}

PostController:

package controllers

import (
    "curd/app/models"
    "fmt"
    "github.com/gin-gonic/gin"
)

func Store(c *gin.Context) {
    // Validate Input
    var post models.PostData
    err := post.Validate()
    fmt.Println(err)
}

{
  "name": "sdfsdfsfsdf"
}

The problem is once I submit the above JSON data from the postman the validation gives me this in terminal :

desc: cannot be blank; name: cannot be blank.

As noted in the comments, you need to decode the data from the HTTP request into the struct before you can perform validation. The validation errors you're seeing are a product of calling Validate() on a fresh instance (with zero values in every field) of your Post struct. Try this.

func Store(c *gin.Context) {
    var post models.PostData
    // This will infer what binder to use depending on the content-type header.
    if err := c.ShouldBind(&post); err != nil {
        c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
        return
    }
    // Validate Input
    err := post.Validate()
    fmt.Println(err)
}