DEV Community: dmacinto

AppDev Week 8

dmacinto — Wed, 22 Feb 2023 02:22:02 +0000

AppDev Week 8

N+1 problem - frequent requests to the database where you also call at the associates

eager loading - pull database once to work with

includes() method in the each do loop to note what to load

queries are where most of hte time improvements can be made

bullet gem can give a warning for N+1 problems

cache-ing - precomputing to save and show later

<% cache “hello” do %>

<% end %>

need to be enabled by rails dev:cache

middle term in the cache statement is the cache key
every time the key is changed, rails will update the cached

in hte belong_to, you can update touch:true to use the parent object as the cache key

kaminari gem used for pagnetnation

API Stuff

jbuilder

json.set!(:hello, “Hello World!”)

or json.hello(“world”)

nested hashes

json.hell(“world”) do

end
 React-native demo

View is like div

yarn start --tunnel to start apps on expo

AppDev Week 4

dmacinto — Wed, 25 Jan 2023 02:51:21 +0000

AppDev Week 4

Crossroads!

2-3 small apps in Ruby

Flutter
React
Ionic.js

react separates frontend from back end, no server side rendering

4 more homework and then a small project that works

assignments
figure out which way Im leaning

ruby notes

attr_accessor creates a getter and setter function for whatever symbol you define

attr_reader creates the getter

initialize method to set up stuff for htat model before doing anything with it

first step is to inspect routes to limit user functionality
each of hte routes if you allow, determine who is allowed
and check the logic
next, don’t show people things they shouldn’t see
use conditional statements to hide things they shouldn’t see
in the view templates

define a before action to help minimize redundant code

gem that helps with authorization

Pundit gem!

remember rails doesnt autoload every folder! if a new one like policies is needed, you must note it

raise exception rather than redirect_back when theres an error

AppDev 2 Week 3

dmacinto — Wed, 18 Jan 2023 02:52:43 +0000

AppDev Week 3

javascript!

Always include jQuery when using javascript
be sure to put the jQuery script as the first element before the script

Be careful of javascript asynchronous movement
Many things operate in parallel so be mindful of the code
To stuff like toggle in a function to help

callback functions

jQuery documentation is great

hover above a link is called a tooltip

put tooltips on the bottom of application layout for best effect. if on top, it will error because it runs before the html runs

better is to use $(document).ready(function(){ put in here}) in the head of the application layout

%i is used for creating an array of symbols

regular expressions are a pattern matching language
checks a string against a certain pattern

Pundit has makes sure you get the authorization correct to hide or show parts of the page, theres a chapter on it

policies folders has a place where we can define methods
becomes the one place where we make the policy on who does what

font awesome is a font set that we use for the discover nav bar

validates :recipient_id, uniqueness: { scope: :sender_id, message: "already requested" }

validate :users_cant_follow_themselves

def users_cant_follow_themselves
if sender_id == recipient_id
errors.add(:sender_id, "can't follow themselves")
end
end

validate is used when wanting to define our own method for validation

I18n is a class where the purpose is to automatically translate our old app into new languages for different users, multiple languages, make a key and then it changes the language, pulled from devise

dom_id is a helper function that simplifies class name and id number into one string

strip_attributes gem is used for setting parameters for user inputs commands like username creation with no white space etc

add remote: true to link_to functions to break the link
add a response in my respond_to block
update the template with the responses I want

escape_javascript method

AppDev Week 2

dmacinto — Wed, 11 Jan 2023 02:42:04 +0000

Always use bootstrap for the basic CSS on a rails app

When using if statements, until you use a method on a variable, it may be blank and may always be true because it will output “ ”

rails db:rollback to rollback 1 migration

If you add a column, you add it to the form, forget that urls can’t be added without permitting the parameter

rails g migration AddDirectorIdToMovies

def the subhashes in the controller function to use it as a local variable

Partials help clean up the CSS on the application layout file significantly

When using render template: and doing a partial, make sure the partial file name has the _ with it.

Locals allows you to pass local variables

https://github.com/heartcombo/simple_form

Bootstrap cards comprise head, body, and footer

All active record objects have a partial path established

Read through the Ruby API documentation on partials

before_action is very useful for repeating actions in the controller, can put in the application controller to make it a little more seamless

%i is a quick way (ruby ) to create symbols

jbuilder is a template for creating json using ruby

Scaffold method to generate stuff very quickly

Use the devise gem for sign-in and sign-out, very boiler plate and easy to use !

AppDev Week 1

dmacinto — Wed, 11 Jan 2023 00:30:24 +0000

resources :movies gives you all 7 routes

a = [1,2,3]

h = { :first => 1, :second => 2}

a.at(2)

h.fetch(“first”)

https://exercism.org/ for more practice

post used to modify the database

post needs to come with a password to ensure that a 3rd party isn’t generating a DDoS type of thing

routes start with the plural name of the table name

use patch for updates, change http verb for different crud functions

delete, patch, post, get

use rails/info on the bin/server url to pull up a listing of all of the routes