If you are new to Rails and want to make your own validation, stop by this finger.

About this article

A free article written by rails beginners for rails beginners. Recently, my friend's children have been rushing to say "** shit !!!!!!!!", so validation to eliminate the sweet idea that ** shit ** would be interesting. The purpose is to make good use of and not to spread vulgar words to the world.



Advance preparation

--Run rails new --Create controllers, models and tables, and set routing appropriately.


This time, if a content containing a word (shit) that is not suitable for the content column of the Post model is about to be posted, we will issue a verification error to protect the world of love and peace of service and prevent spreading dirty words. ..

Posts table columns

ActiveRecord::Schema.define(version: 2018_06_10_125752) do

  # These are extensions that must be enabled in order to support this database
  enable_extension "plpgsql"

  create_table "posts", force: :cascade do |t|
    t.string "title", null: false
    t.text "content", null: false
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.bigint "user_id", null: false
    t.index ["user_id"], name: "index_tasks_on_user_id"

Now, let's add a method for validation to the Post model.

Step 1

I will register the method for verification.

class Ppst < ApplicationRecord
  validate :validate_content_not_including_unko

Hey, isn't there something strange?

Those who have studied Rails to some extent here will want to put in a tsukkomi. so! !! !! That there is no ** validate ** in the third person singular present (third person) s ** instead of ** validates **! !! !! !! The difference between the two seems to be either custom or self-made validation.

Apparently, when using custom validation, use ** validate **. .. .. Horrible and difficult to understand https://guides.rubyonrails.org/active_record_validations.html#custom-methods

Step 2

I will implement a method for verification

class Ppst < ApplicationRecord
  validate :validate_name_not_including_unko


  def validate_content_not_including_unko
    errors.add(:content, 'If you write this, you can't! !! !! !!') if content.include?('shit')

①private Since this method is not used from outside this object, it is described below private

validate_content_not_including_unko The job of the validation method is ** "If you find a validation error, put the error content in errors" **. Therefore, when content.include? ('Unko') contains shit in the content column, the content of the verification error is included in errors.add.

Check if poop spreads in the world.

スクリーンショット 2020-11-13 14.52.28.png

This will stop you from saying that bad boy. .. ..


There is one thing I thought through this article that it had nothing to do with it.

Instead of making it possible to post suddenly by typing a sentence on Twitter or pressing the post button, to take a breather on the confirmation screen once, "Are you saying or acting like being dried?" I wondered if I could reduce the number of sentences that would be emotionally written and spread some kind of adverse effect.

Also, I'm sorry I had a lot of poop.

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