The main aim of this mini reddit is to get an idea on the rails

1. Assosiactions
2. Validations

At the end the main aim of this application is to create simple blog app the features are.

• User signin
• Blog post creation
• Commenting

rails g model User username:string email:string password:string

This will create bunch of files but the most focused one is app/model/user.rb this is the where we write our validations.

After write validation according your choice & run the migration using rails db:migrate

validates :username, presence:true
validates :email, presence:true, uniqueness:true
validates :password, presence:true, length: {minimum: 8}

We can create blog post just modifying the above command little bit but the trick is we need to connect the user model with post model

rails g model Post title:string context:text user:references 

If you observe that connection is nothing but referencing the User model with Post model, also change the associations accordingly & add validation to the Post model

validates :title, acceptance: { message: 'Must container title for the blog'}
validates :context, acceptance: { message: 'Must containe context for the blog'}

If your observe shema.rd file your will see there is addition of foreign_key related to user_id in the post table this is responsiblr for connecting the 2 models

note: while creating a post don't forget to add the user_id other wise it will through you an error

Unless post model while creating Comment we need to reference both User & Post Model

rails g model Comment comment:string user:references post:references

change the assosiations & validations accordingly

validates :comment, presence:true

    has_many :posts, dependent: :destroy
    has_many :comments, dependent: :destroy

belongs_to :user

  belongs_to :user
  belongs_to :post