railstips

[railstips]

http://strftime.net/

http://strftime.net/

[railstips]

rails new created a lot directories and files

[railstips]

Pinterest Clone

My take on Pinterest

rails new pinterest

[railstips]

Add Bulma to Rails

gem bulma

bundle install

@import "bulma";  in your css

In your application.css, rename file to application.scss and add

 @import "bulma"; at bottom of file

[railstips]

twittr clone notes

rails new twittr

rails g scaffold Tweet tweet:text

gives use views, models, controllers

rails db:migrate

Set the root route

Rails.application.routes.draw do  

  resources :tweets  

  root "tweets#index"

end

We already had esources :tweets  from the scaffold earlier.

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gem 'sqlite3', '~> 1.3.6'

For some reason on my ubuntu machine I need to change version of sqlite in the gem file.

Open the Gemfile inside my_first_rails_app and change gem 'sqlite3' to gem 'sqlite3', '~> 1.3.6'

https://forum.theodinproject.com/t/sqlite3-error-when-trying-to-migrate-the-database-2-3-first-rails-app/15578/10

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localhost:3000/rails/info/routes

Great way to show routes and nested routes in your app.  Better than rails routes

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generating a resource

rails g resource registration name:string email:string how_heard:string event:references --no-test-framework

--no-test-framework ( now you won’t get the test stubs)

You get a ton of stuff.

     invoke  active_record      create    db/migrate/20190308120206_create_registrations.rb      create    app/models/registration.rb      invoke  controller      create    app/controllers/registrations_controller.rb      invoke    erb      create      app/views/registrations      invoke    helper      create      app/helpers/registrations_helper.rb      invoke    assets      invoke      coffee      create        app/assets/javascripts/registrations.coffee      invoke      scss      create        app/assets/stylesheets/registrations.scss      invoke  resource_route       route    resources :registrations

rails db:migrate

Now in registration.rb 

class Registration < ApplicationRecord  

   belongs_to :event

end

Now we can assign an event to a registration.

[railstips]

gem update --system

So I was having an issue in Visual Studio Code, one of the Rails extensions was giving me error: Failed to start Solargraph 

one answer suggested running 

gem update --system

And I’m glad I did as it installed all kinds of enhancements and bug fixes and...

after a bit more digging around ran...

gem install solargraph

Updating rubygems-update Fetching rubygems-update-3.0.3.gem Successfully installed rubygems-update-3.0.3 Parsing documentation for rubygems-update-3.0.3 Installing ri documentation for rubygems-update-3.0.3 Installing darkfish documentation for rubygems-update-3.0.3 Done installing documentation for rubygems-update after 83 seconds Parsing documentation for rubygems-update-3.0.3 Done installing documentation for rubygems-update after 0 seconds Installing RubyGems 3.0.3 Bundler 1.17.3 installed RubyGems 3.0.3 installed Regenerating binstubs Parsing documentation for rubygems-3.0.3 Installing ri documentation for rubygems-3.0.3

=== 3.0.2 / 2019-01-01

Minor enhancements:

* Use Bundler-1.17.3. Pull request #2556 by SHIBATA Hiroshi. * Fix document flag description. Pull request #2555 by Luis Sagastume.

Bug fixes:

* Fix tests when ruby --program-suffix is used without rubygems  --format-executable. Pull request #2549 by Jeremy Evans. * Fix Gem::Requirement equality comparison when ~> operator is used. Pull  request #2554 by Grey Baker. * Unset SOURCE_DATE_EPOCH in the test cases. Pull request #2558 by Sorah  Fukumori. * Restore SOURCE_DATE_EPOCH. Pull request #2560 by SHIBATA Hiroshi.

=== 3.0.1 / 2018-12-23

Bug fixes:

* Ensure globbed files paths are expanded. Pull request #2536 by Tony Ta. * Dup the Dir.home string before passing it on. Pull request #2545 by  Charles Oliver Nutter. * Added permissions to installed files for non-owners. Pull request #2546  by SHIBATA Hiroshi. * Restore release task without hoe. Pull request #2547 by SHIBATA Hiroshi.

------------------------------------------------------------------------------

RubyGems installed the following executables: /home/dom/.rbenv/versions/2.6.1/bin/gem /home/dom/.rbenv/versions/2.6.1/bin/bundle

Ruby Interactive (ri) documentation was installed. ri is kind of like man pages for Ruby libraries. You may access it like this:  ri Classname  ri Classname.class_method  ri Classname#instance_method If you do not wish to install this documentation in the future, use the --no-document flag, or set it as the default in your ~/.gemrc file. See 'gem help env' for details.

[railstips]

generate a Rails App with a postgresql database

rails new app-name -d postgresql

-d postgresql  is optional and allows us to use postgresql database.

in database.yml under default: &default enter username:postgres below adapter and encoding and above pool:5

before starting the rails server run 

rails db:create

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Adding Bootstrap to a Rails App

Some older Rails tutorials or ones using cloud ide's running 4.2 recommend bootstrap-sass gem. "a Sass-powered version of Bootstrap 3, ready to drop right into your Sass powered applications".  That was Bootstrap 3. For Bootstrap 4 use the Bootstrap ruby gem.​​

THE GEMS

gem 'bootstrap', '~> 4.2.1'

Bootstrap JavaScript depends on jQuery If you're using Rails 5.1+, add the jquery-rails gem to your Gemfile: gem 'jquery-rails'

bundle install and restart your server to make the files available through the pipeline.

CSS

If you have just generated a new Rails app, it may come with a .css file instead. If this file exists, it will be served instead of Sass, so rename it:

$ mv app/assets/stylesheets/application.css app/assets/stylesheets/application.scss

Then, remove all the *= require and *= require_tree statements from the Sass file. Instead, use @import to import Sass files.

The file should then contain depending on number of scss files.

They all need to be imported as we deleted require_tree which would bring them in automatically.

// Custom bootstrap variables must be set or imported *before* bootstrap.

@import "bootstrap";

@import "events";

@import "layout";

@import "show";

JAVASCRIPT

Bootstrap tooltips and popovers depend on popper.js for positioning. The bootstrap gem already depends on the popper_js gem. Add Bootstrap dependencies and Bootstrap to your application.js:  above //= require tree  .  (pulls everything in from the js directory). //= require jquery3 //= require popper //= require bootstrap-sprockets

[railstips]

The new, modern clearfix hack

The new, modern clearfix hack however, is safer to use, and the following code is used for most webpages:

.clearfix::after {  content: "";  clear: both;  display: table; }

The Old Way

The overflow:auto clearfix works well as long as you are able to keep control of your margins and padding (else you might see scrollbars).

source. w3schools

[railstips]

layouts / patials

If you create a partial to render to a file in layouts folder your partial must go there too.

Same if you render to a file in the events folder like a form partial for new and edit forms the partial goes in the events folder.

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migrations - rollback previously applied migration

rails db:rollback

== 20190304195318 AddImageAndCapacityToEvents: reverting ====================== -- remove_column(:events, :capacity, :integer, {:default=>1})   -> 0.0177s -- remove_column(:events, :image_file, :string, {:default=>""})   -> 0.0050s == 20190304195318 AddImageAndCapacityToEvents: reverted (0.0412s) =============

rails db:migrate:status

The status of the last migration is now down so we can go in and change the column name for example.

save then reapply the migration

== 20190304195318 AddImageAndCapacityToEvents: migrating ====================== -- add_column(:events, :image_file_name, :string, {:default=>""})   -> 0.0029s -- add_column(:events, :capacity, :integer, {:default=>1})   -> 0.0007s == 20190304195318 AddImageAndCapacityToEvents: migrated (0.0038s) =============

When you roll back the columns aren’t deleted when you run db:migrate again they will be added again minus any data that was previously entered.  Rolling back is just good for editing columns etc..

[railstips]

migrations - create new columns

rails g migration AddImageAndCapacityToEvents image_file:string capacity:integer

Adds 2 columns to the events table

class AddImageAndCapacityToEvents < ActiveRecord::Migration[5.2]  

def change  

  add_column :events, :image_file, :string    

  add_column :events, :capacity, :integer  

  end

end

Add the default values manually

   add_column :events, :image_file, :string, default: ""    

   add_column :events, :capacity, :integer, default: 1

save then rails db:migrate

[railstips]

thinking about objects using real life objects

OBJECT: COMPUTER

Attributes

Type: Macbook

Maker: Apple

Year: 2015

Methods (functionality - a thing the object can do)

Turn On

Shut down

Create a file

[railstips]

Making the index page a bit more interesting (custom queries)

Early on in a rails project you might just list out all posts, tweets, events (whatever the CRUD is).

def index      

  @events = Event.all   

 end

THE WRONG WAY

allowing controller to make decisions about which events to display. Old events are gone and soonest at top of list.  It’s the models job to get the data.

def index       

 @events = Event.where("starts_at >= ?", Time.now).order("starts_at")   

 end

A Better Way

Don’t put your query code in controller/views push it to methods that are defined in the model. (here event.rb)

class Event < ApplicationRecord  

# if an event is free it is business logic, so goes in model   

def self.upcoming  

      where("starts_at >= ?", Time.now).order("starts_at")    

 end

end

In the controller 

def index        

 @events = Event.upcoming    

end