Today I Learned

TIL, 2018-04-28, We're Back

Musings, Back-end and Ruby

  • Rails loads the I18n, you need to load it outside of Rails with I18n.load_path += Dir["#{app_path}/config/locales/**/*.yml"] Reference
  • File.realpath("symlink_path") to get the target of a symlink. Reference
  • Removing a scaffold in Rails: rails d scaffold SCAFFOLD_NAME.

  • Habitat: used for the app, Chef: used for provisioning the server.
  • 10 Common Software Architectural Patterns
    • Layered: Subtasks, each of which is at a particular level of abstraction. Presentation/application/business logic (domain)/data access (persistence).
    • Client-server.
    • Master-slave: used in DB replication.
    • Pipe-filter pattern: Each step is ran through pipes, and can be used to sync or for buffering.
    • Broker: Structures distributed systems with decoupled components. A broker is responsible for the coordination of communication among components. Servers publish their capabilities to a broker: clients request a service from the broker, and the broker then redirects the client to a suitable service from its registry.
    • Peer-to-peer.
    • Event bus: Sources publish messages to channels on a bus, and listeners are notified.
    • MVC.
    • Blackboard.
    • Interpreter: SQL, languages used to describe communication protocols.
  • alias vs alias_method: Reference, Reference
    • If you implement alias, when you call the aliased method in a child class, the child class calls the aliased method in the parent class.
    • Ruby style guide: “prefer alias when aliasing methods, so it communicates to the user that your alias will not be altered at runtime or by any subclass unless explicit.”
    • alias is a keyword and is lexically scoped: it treats self as the value of self at the time the source code was read.
class User

  def full_name
    puts "Johnnie Walker"

  def self.add_rename
    alias :name :full_name

class Developer < User
  def full_name
    puts "Geeky geek"
end #=> 'Johnnie Walker'
  • On skills:
    • Side projects, contributing to open-source, hacking on Github, enthusiasm for cool shit/software.
    • Learn about code quality, show that you care about it.
    • Teach the world that developers are more than their resumes.
    • Of course, experience matters, but it’s not everything.
    • 15 years of experience, of 1 year of experience repeated 15 years in a row?
  • Readline in the Ruby library: require 'readline'
  • parslet: Parsing expression grammar?
  • Regex: ^ as not?

  • DAS 83: Test cases vs example
    • Hamster vector library?
    • Representing test cases not as things that happen, but as human-readable output.
    • You can put test helpers to make the thing terse/readable.
    • By doing shit like def_delegator, it’s testable literally by doing an alias anyway.
    • If you can rewrite a class such that the value just relies on everything inside of it, why not?

    • Bitcoin mining inside of a Browser?

Reading Serverless Stack Book

  • Amazon Cognito. Wow. Amazon really does a lot of things.
  • DynamoDB: Is this
  • CloudFront: Create distribution, has custom error responses.

Musings, React

  • When to state and when to props?
    • Props flow downward from the parent component.
    • When a component receives data from someone other than the parent, we can use state.
    • State: for data that will change.
  • Medium posts: I like gists for this, for interpolation shit.

This project is maintained by daryllxd