Development

Stacked pull requests really do suck to deal with. When the change you are making is so large that it becomes extremely difficult to review and when you do have reviews and changes requested mid stack, it becomes a nightmare to have to rebase and untangle. There is a lot of book keeping involved in order to keep the stack up to date. Stacked PRs seem to have garnered favor because developers are pushing larger and larger changes to the point that it is down right impossible for developers to review in totality, so the initial reaction is to simply stack them and try to keep the focus on just that change and disregard the later changes that build on it or use the new stuff being introduced. ...

Postgres 11 has a nifty feature around partitions. When a partition exists for a range of values, when you insert into the parent table it’ll get routed to the correct partition. When you update that record’s partition key it will get moved to the correct partition. A default partition feature exists as well so that if you do try to insert something that doesn’t belong in any available partitions, it will be put there instead. ...

Service objects are a handy tool to use in any ruby application, that has complex logic that needs to be extracted out of a controller or model. There are some nice benefits to extracting complex things into a more testable interface. To avoid providing a contrived example, I will use similar code to how uploads on rubyfm are handled. class UploadService attr_reader :user, :logger, :upload def initialize(user, options = {}) @user = user @logger = options[:logger] || NullObject.new @errors = {} end def start(params) @upload = build_from_params(params) unless @upload.save logger.error { 'failed to save the upload' } # more logging info on why return false end unless transcode logger.error { 'failed to transcode upload' } return false end true end def transcode AmazonTranscodeService.new(@upload).start end end And the UploadsController that utilizes the UploadService with the following. ...

I’ve been writing a lot of C lately for a game I am working on. I am not a perfect programmer and I would like to catch my bugs before they arise. Thus, I am attempting to learn Rust in my free time. Backtrace Printing a backtrace in C is not incredibly difficult to accomplish. Although the following is fairly primitive, it will aid in your ability to discern what is happening in your program ...

Mixins are a bit of a touchy spot for me. I am in a love hate relationship when it comes to them. In some cases, they work brilliantly and in other cases they hide complexity. I have a few rules that I try to follow when I am considering using mixins. Does it hide complexity / indirection? Will it benefit the code base to share code? Will it override methods or will methods need to be overriden? Moving methods into mixins to just move them is not sufficient enough to warrant the need for mixins. It is something that should be used to refactor once a pattern is established. Mixins should only be used for adding abilities to classes. ...

Let me introduce you to my new library called Yukata. It is a light weight Ruby attribute library that is configurable and extendable. Virtus has been a huge inspiration for this library. I enjoyed the DSL it offered, while allowing me to have a quick way to make data objects. Here is an example on how to utilize Yukata: class Person < Yukata::Base attribute :first_name, String attribute :last_name, String attribute :born_on, DateTime attribute :married, Boolean, default: -> { false } end The #attribute method is straight forward with its meaning. It is dynamically creating both getter and setter methods for the object. It can be thought of as a fancy attr_accessor but with a few extra features. It provides a fast way to discover what data type can be expected for that attribute. ...

As I work on API projects I find myself having to track down status codes and ensuring a consistent response code for any given error. Keeping these status codes consistent throughout the application starts to become a hassle. A solution that I stumbled upon happened to be something very simple. # /lib/errors/unauthorized_access_error.rb module Errors class UnauthorizedAccessError def status 403 end def message 'unauthorized access' end def to_hash { meta: { code: status, message: message } } end def to_json(*) to_hash.to_json end end end In my controller I would do the following: ...

Test spies are a wonderful tool to utilize in the RSpec testing environment. When used in moderation and with care. Test spies require that a called method be stubbed so that it can be checked to see how it was invoked. I have put together a really simple class to demonstrate a test spy. class NotifyUser attr_reader :user def initialize(user) @user = user end def execute(params={}) mailer.notify({ message: params[:message] }) end def mailer SomeMailer.new(user) end end Notice in the test below that a test spy follows a pattern. There is a mock up section, an excercise section, and a verification section. Each of these are important and I always put a space in between the sections. It’s much easier to see what is happening in the test. ...

In any Unix based OS the command line reigns supreme. Commmands are predictable, and return zero for success and non-zero for failures. Rules The same principles can be applied to programming with some minor rule alterations. Class name must be in a similar format to VerbNoun (ex. CreateResource). Instance must have an #execute method. It can accept arguments. The only instance method that should be accessed is the #execute method. The return type for #execute must be a Boolean. Example A basic command object will look like the following: ...

A state machine is an interesting design pattern. The state_machine gem is a great library. It provides a nice structure to declare states and transitions. It also provides nice callback hooks that can be utilized to run specific actions before or after a transition happens. It has hooks into ActiveRecord and saves the model when the transition from one state to another is successful. The gem also works just fine with plain old ruby objects as well. Here is a simple example of a state machine. ...