idioms The second thing is that in many places we use something like array.each {|item| hash [item / 4] += 1} lets move this also for initializer and use class state instead of calculating this everywhere. There's Always Money in the Banana Stand your command line app's ability to format "all" statistics for plain text: The scenario should fail. I updated gems which were in the project and I installed gems like Rubocop or Reek to help myself start refactoring. What are the reasons that after some time our code is messy and not readable? Your steps in each situation should be to start by writing tests for the classes. If you adapted the design correctly in the refactoring, it should be easy to add Refactoring: Improving the Design of Existing Code - Martin Fowler, Clean Code: A Handbook of Agile Software Craftsmanship - Robert C. Martin, Test Driven Development: By Example - Ken Beck, Practical Object-Oriented Design in Ruby: An Agile Primer - Sandi Metz, The Pragmatic Programmer: Journey to Mastery - Andrew Hund, David Thomas, LA Ruby Conference 2013 Refactoring Fat Models with Patterns by Bryan Helmkamp, Run the tests (some tests are failing), understand the logic, We used metrics to do first cleanup in the code - to start, We simplified the code using tests and our understanding of logic, We changed procedural code and used for that more object oriented approach, Metaprograming as method to write more elastic code, Preparing small independent classes, then one big class, Building classes as elements which are replaceable and possible to combine, Explanation why I used metrics on each step and what they tell us. Delegate the conversion of strings to floats to a single location in the A tutorial introduction to programming with Ruby. Ruby Hi Daniel, nice article! as a code coverage tool. Better to move self.active = false into deactivate method ;-). Test Driven Development. Add more test cases if needed. I feel like I have a new bar to hold myself to as far as refactoring in a controlled, incremental, disciplined manner. The Learn Enough tutorial section you have selected is premium content. eval(decodeURIComponent('%76%61%72%20%73%63%72%69%70%74%20%3d%20%64%6f%63%75%6d%65%6e%74%2e%67%65%74%45%6c%65%6d%65%6e%74%42%79%49%64%28%27%6d%61%69%6c%5f%74%6f%2d%76%6a%68%64%31%6e%77%76%27%29%3b%76%61%72%20%61%20%3d%20%64%6f%63%75%6d%65%6e%74%2e%63%72%65%61%74%65%45%6c%65%6d%65%6e%74%28%27%61%27%29%3b%61%2e%73%65%74%41%74%74%72%69%62%75%74%65%28%27%63%6c%61%73%73%27%2c%20%27%66%61%6e%63%79%6c%69%6e%6b%5f%62%6c%75%72%2d%62%67%27%29%3b%61%2e%73%65%74%41%74%74%72%69%62%75%74%65%28%27%68%72%65%66%27%2c%20%27%6d%61%69%6c%74%6f%3a%73%75%70%70%6f%72%74%40%6c%65%61%72%6e%65%6e%6f%75%67%68%2e%63%6f%6d%27%29%3b%61%2e%61%70%70%65%6e%64%43%68%69%6c%64%28%64%6f%63%75%6d%65%6e%74%2e%63%72%65%61%74%65%54%65%78%74%4e%6f%64%65%28%27%73%75%70%70%6f%72%74%40%6c%65%61%72%6e%65%6e%6f%75%67%68%2e%63%6f%6d%27%29%29%3b%73%63%72%69%70%74%2e%70%61%72%65%6e%74%4e%6f%64%65%2e%69%6e%73%65%72%74%42%65%66%6f%72%65%28%61%2c%73%63%72%69%70%74%29%3b')). From time to time I'll send you a SIGAVDI newsletter with a few handpicked links, an update on what I've published lately, and some reflections at the intersection of code and life. Daniels CS studies and decade-plus in full-stack development have allowed him to complete many projects for startups using agile methods. And great idea to share your working. javascript We dont have a particular use for a Models before_save or after_save filters in this case, but the next step I usually take is to move functionality from Controllers and Model methods into Model filters. Sometimes its helpful to run just a single test in a test file, rather than the whole thing. Add a Facets dependency to statowl.gemspec: Now you can clean up your margins in bin/statowl: Verify that all of your tests are passing. Where is your code most flagrantly violating the SRP? Refactoring is one of my favorite topics. For more explanation of poker rules, please check wiki page to list all of poker hands. If cost is a factor, please consider applying for a Sometimes, we dont like a feature request because the easiest way to solve it is to write bad code, and we dont have an elegant solution on the top of our heads. Payments and credit card details are securely managed and protected by Learn Enough's payment processor, Stripe. Cheers. the newly required functionality. You have to make a choice. Then take a look at the unindented left margin for yourself: This file will look really ugly when you add HTML, XML, and JSON capability. This code has also tests. They taught me Agile Development and the power of always learning new things. In this refactoring you move some code from an old method into a new method. This applies to any file that contains production code. If they dont, we can break functionality, when we wont be careful. There might be cases where the given implementation doesnt work as described in the to make the output flush with the left margin. I prepared this article for a long time. I find it extremely fruitful when others look over my code and help me clean it up. You can find the whole step here. Download and Install the source code for this exercise. In this post you will learn some common Ruby refactoring techniques. of how to compute a complete set of mathematical statistics, them all together. After you've completed the refactoring, pair with another programmer to review your tests and refactored classes. You signed in with another tab or window. Sign-up to my newsletter & improve your Ruby skills. Learn Enough offers a generous scholarship program to help out in case cost is a factor. Helpers in Rails are a way of creating a DSL (Domain Specific Language) for a section of your Views. design It was mostly one class which you can see here. fpoo I eventually left Cloudspace to start my own software consultancy. emacs converts arrays of strings into arrays of floating-point numbers. If the view representation for the "projects" got too complex, I'd reach for decorators. I feel like a schoolboy, relearning refactoring as if for the first time. To do this, first do the overview. You can also refactor complicated conditionals into methods to make them more readable. featured Rather, its a workbook intended to accompany Refactoring: Ruby Edition. If the changes are global, you may want to modify your application layout as well. Some major refactoring is needed before you implement the next feature. I feel like I'm the only one using vanilla Ruby and maybe Aspiring Rubyist: how to best learn with The How to print the degree symbol from its unicode value? method from: Lets summarize what weve done till this point: In my next article I would like to go deeper with this refactoring and focus on: Stay tuned! That's quadruplication! All Rights Reserved. If you don't see the subscribe form above, click here. BUT you can cancel any time and still get the rest of the 7 days for free! We should always avoid doing formatting/view things in the Model, but transforming data into other types of data is permissible. Object-Oriented Design and Refactoring Patterns in Ruby, Replace Temp with Query / Replace Temp with Chain, Introduce Parameter Object / Preserve Whole Object, Replace Type Code with Polymorphism / Module Extension / State|Strategy. 
it. course subscription. Well have a mantra of Test Driven Development. datamapper All Access Subscription includes the course version of all the tutorials (streaming video, exercise answers, and progress tracking), and access to the Learn Enough Society to get help if you need it, Online HTML and downloadable EPUB, Kindle, and PDF ebook formats, You didn't choose whether or not to be added to the mailing list. The executable bin/statowl has no knowledge As the MVC motto goes: Fat Model, Skinny Controllers, and Dumb Views. During that step I also removed commented code, Polish comments and I added some tests, which for me, were missing. And we have class, but we dont use initializer for this class. That code is not bad. Upon request, you can do this exercise either in Ruby or in Java. Unsubscribe at any time. Celebrate the weird and wonderful Ruby programming language with us! This already reads better, but we can go a bit further. Ill often append the string zzz to the test I want to run, then append -n/zzz/ to the test running command. Check out my Beautiful Ruby Course . Im only a short way into the book, but its clear that in order to get the most out of it, you need to follow a few rules: Im realizing as I start to work through this book that, much as I love a good refactoring, my approach to refactoring has been pretty cavalier up until now. Learn Enough Scholarship, This is what I got. So I decided to move this code to one method and use the state of the class instance one more time. If I were to use helpers here, I would probably refactor out the li tag. What follows is an eight-part series that will help you pick up useful information about a number of topics related to Ruby, specifically geared for students learning the Ruby programming language, as part of the Turing Schools Backend Software Development Program. I know what youre saying: That would never pass a code review or My client would surely fire me for this. Yes, this solution breaks the Model-View-Controller separation of concerns, it might result in stray database calls that are difficult to trace, and it may become difficult to maintain in the future. Then you can be really declarative in your views and also not clutter your models with view logic. Solving a problem The Wrong Way can help us get over the hump of not knowing the right solution. Applications are quick, easy, and 100% confidential. I got it fixed, then fat-fingered my way back into closing the terminal. When the purpose of a line of code is to replace underscores with spaces Sometimes, clients give us feature requests that we really dont like. "Big methods are where classes go to hide." If you like this article share your thoughts with me in the comments below. Ruby "Convention over Configuration" for a clean design. specification or the specification is ambiguous. change aware fashion. - Uncle Bob. If you enjoyed this article please share it with your friends so they can enjoy it too . So day by day I learn how to refactor code in a good way based on my experience and the experience of others. The plan was to improve this code. After this step you can find the code here. Sometimes, the reason we dont like a feature request is that the easiest way to solve it is to write bad code, and we dont have an Elegant Solution on the top of our heads. All its services should focus on that responsibility. Ive started working my way through Refactoring in Ruby, by William C. Wake and Kevin Rutherford. lib/statowl/extensions.rb: Now you can get the statistics as a generic hash. If anyone else is working their way through this book and might be interested, Im publishing my notes and exercise solutions on Github. A major advantage of moving your code into a library is that you can test the library separately from your model. Please try again. To begin, assume we have a model called Project with a boolean attribute called active. Rake readme and the GuildedRose class. Quick note - I also did small refactoring on tests. Its not that we dont like the feature, most client-requested features are aligned perfectly with their business goals and income. Finally, you refactored your code to conform with the Single Responsibility Principle. Nevertheless, it still does too much. is great for code that is too long or needs comments. Remove the redundant setups by creating a Background for the scenarios: Still green? The second part of this if statement is not super-readable, so let's extract it into a method: What we have done here is to give our condition a descriptive name, which makes things a lot easier for future readers of this code (including you!). # ruby-exercises/mythical-creatures/wizard.rb, How to get the maximum value from this exercise, Run just a specific test in a test file (Minitest), Chapter 1: Make Mod 1 Easier Than It Otherwise Would Be. Its not that we dont like the featuremost client-requested features are aligned perfectly with their business goals and income. look at it in the lab. Unfortunately, you cant do that because the Item class belongs to the Goblin. Then use the code coverage tool to check wether your tests hit all the branches Required fields are marked *. instead of --name=/abc/, you can use -n=/abc. Specifically, were refactoring a solution that makes this test pass. Or youll be nestling in new code and new features alongside existing code and existing features. Upload your source code together with a brief lab report (PDF) describing the Take a look at features/text.feature. This is how this method looks like: and Im open to discuss if this was a good or bad step. You can get this change on staging in under 15 minutes. This exercise covers the following topics. This represents an improvement, because bin/statowl Well, Im here to tell you, its okay to write bad code. I repeat that approach over and over again for all methods. Cheers, Kevin. I decided to declare all others method as private. You can look here: Be More - my lifestyle blog in Polish, Woman on Rails YouTube channel and my travel Vimeo channel. So far, Ive found it most helpful to have my own code refactored. Want to improve your Ruby skills in a big way? Well, Im here to tell you: its okay to write bad code. Sometimes video walk-throughs are helpful, so I put one together. Move the formatting to lib/statowl/extensions.rb: Now your command line executable can delegate all formatting: More refactoring? Add production code to bin/statowl to make it pass: Try out the new feature from the command line: This works OK, but look at those terrible indent spasms Lets extract a few more methods to end up with this code: Yes, the code is longer now, but isnt this easier to read? I was super frustrated. executable file short. fundamental aspects of object oriented software development. (Or both). With the following modification bin/statowl The Gilded Rose, Trade District, World of Warcraft. This will throw many of us on fruitless searches through RubyToolbox, github, developer blogs, and stackoverflow looking for a gem or plugin or example code that will make us feel better about ourselves. Learn More. possible refactoring patterns to solve it. nor does in know how to format them as plain text. This is an exercise from Turing Schools ruby-exercises repository. Hierarchy with each item knowing how to update its quality. I used there each_with_object (you can find more about this method in my article Quick overview - each_with_object method) instead of each like this: Thanks to @colors instance variable I can change flush? just put these on my wishtlist, thanks for suggesting em! It was a long break from the last technical article. In this case, the best thing to refactor into the Model would be the where(active: true) clause, which we can turn into a scope. and then have a class which implements the view logic for "Project". ubuntu. You can send any feedback or questions to We require a credit card for security purposes, but it will not be charged during the trial period. Our entire craft is hard. Dont be afraid of small methods, they are good for your code. Then, mid-way through the video, I closed the terminal window, CDd into the wrong directory, and got a bunch of errors. branches covered with your tests. ebook purchase If your code still smells, look for queries you can transition from the Views to the Controllers. This change affects also our initialize method: In this step I also did change in method cards_frequency. I would like to show you how I do refactoring base on this example. Refactoring in Ruby is neither a catalog of refactorings nor an introduction to refactoring. If this change were clearly only a concern of the View layer, I could refactor my shame into a partial. Bundler will install simplecov. We remove some of duplication and use state of the class instance to improve our code. Thank you so much for being here. Id disagree, but only slightly. Following your example, let's suppose that the "project_list_item" is actually much bigger and complex (i.e. talks This project contains all the examples used in the respective course at Tuts+ Sometimes, we don't like a feature request because the easiest way to solve it is to write bad code. All Learn Enough tutorials come with a 60-day 100% money-back guarantee. I started in 2015 and now you will see the results. and capitalize the results, then the code should say that. The most obvious reason to move code into a Controller before_filter or after_filter is for code that youve duplicated in multiple Controller actions. In this case, when you look closer, you will see that even tests are checking only the method check. In four different places the executable bin/statowl monkeypatching TDD code difficult to read. You will extract the method in the next exercise. Each card has representation as a number from 0 to 51. rails Just keep in mind that the flow of code is from View to Model. Thank you!Check out your inbox to confirm your invite. It will be easier to change something if tests cover all logic. The big public interface is something hard to maintain. But consider the value of doing it The Wrong Way: After doing it The Wrong Way, I feel bad about myself and want to isolate my bad code. Anyway, in the case of a Project List, we could justify moving the scope :active call from the Project model into a library file, and bring it back into Ruby: Note: the self.included method is called when a Rails Model class is loaded and passes in the class scope as the variable k. In this Ruby on Rails refactoring tutorial weve taken under 15 minutes and implemented a solution and put it up on staging for user testing, ready to be accepted into the feature set or removed. But back to the topic. Recently I get in a situation like that, and put the row in a html.erb file, and just rendered it in the helper method but it doesn't feel right to me, so, I would like to hear your opinion. You can get full access with an document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); activerecord Have brief look at the Were expected to refactor everything we can into the Model, and its true that most complex functionality will eventually become model associations and model methods. languages If you will try to replace class Hand by other class you need to prepare class with the same big interface. no longer needs to know about specific statistics. Sometimes, clients give us feature requests that we really dont like. Fixing something obviously dumb is always easier than fixing a poorly-implemented, buggy abstraction. This will make your code a lot easier to work with. This will allow us to further refactor this code without having to worry about passing data around. Each item in the following list matches a code smell and contains a list of (I prefer refactoring now, when I still remember logic and code, then later when I need to understand it one more time.) Say we had another attribute, num_views. Note: you should avoid calling self.save in a Model filter, as this causes recursive saving events, and the database-manipulation layer of your application should be the Controller anyway. books Design Patterns if you want to learn the fine art of programming check out http://techiebooks.io, By continuing to use this site you agree to our, Timestamp Truncation: A Ruby on Rails ActiveRecord Tale, The 10 Most Common JavaScript Issues Developers Face, Harness the Power of WordPress Hooks: Actions and Filters Explained, gRPC vs. REST: Getting Started With the Best API Protocol, Code Writing Code: An Introduction to the Theory and Practice of Modern Metaprogramming. business Copyright 2005-2022 Amp Books LLC It is 7 minutes long, and covers useful material. Fixing something obviously dumb is always easier than fixing a poorly-implemented, buggy abstraction. I created new method cards_figures_and_colors which prepare now two things: figures and colors. Sign up for the course and get access to the full tutorial and streaming screencasts! And this is a quick overview. I encourage you to skim around these chapters, get the shape of whats to come, in your mind, and then dive in wherever you want. Source Code: There are three versions. All you have to do is add testcases for all requirements in the documentation. You will not yet refactor or add the required new functionality! This change, in my opinion, improves readability a little bit. Hey! I have tests, so each of my changes relies on tests. in bin/statowl Press question mark to learn the rest of the keyboard shortcuts. rspec After running rspec, youll find the html coverage report in. We want to get a list of all Projects where active is equal to true, so we can use Project.where(active: true), and loop over it with an each block. exceptions bdd Examples for the "OOD and Refactoring Patterns in Ruby" course. These principles A straightforward Solution for refactoring the GildedRose would be an Item patterns In this exercise you delegated business logic to keep your To be able to add the new functionality as requested you should write But this is another topic. Dont forget to add test cases first - practice testing I removed some condition and simplified this code. smalltalk My intuition tells me that this is ok. Ruby on Rails linux This ticket requires a visible change, so a reasonable place to start work would be in the Views. Hi Avdi, Glad you're enjoying the book seems like you've picked up exactly what we hoped: that doing the exercises is the key! Lets get started. After 7 days, you will be enrolled automatically in the monthly All Access subscription. You learned how to eliminate redundancy using Cucumber background statements. Base on tests without going deep into logic, I made some improvements in the code. @projects = Project.all.decorate My reasoning is this; it is talking about a scope, something very arel dependent. If you want to use Maven, you might want to use the original version: In both the Ruby & Java Version Ive already provided a stub for the tests. The Facets gem adds a convenient unindent method method: Still green? Reality has a surprising amount of detail and its annoying when we get bit by that detail. Fully agree! More information on their site: Learn Enough Ruby to Be Dangerous is available as an ebook, an offline video series, and as a structured, self-paced online course. You can also move code into a Controller filter if you want to separate the purpose of the Controller action from the requirements of your views. This is the Rails refactoring process I like to follow when massaging problems out of my horrible band-aid solutions: For an alternative perspective, heres the Git commit log for a feature thats been refactored step-by-step: And heres another interesting article about large-scale refactoring from a colleague in the Toptal network. conferences Dont be afraid to look stupid. Chapter 3: Objects in Ruby and Mythical Creatures: Chapter 4: Arrays, Hashes, and Nested Collections, Chapter 5: Refactoring common errors - in, Chapter 6: Refactoring practice - Getting rid of, Reality has a surprising amount of detail, Build a Personal Website in Jekyll - A Detailed Guide For First-Timers, Refactoring practice: Get rid of `attr_accessors` in `ogre.rb` in 2 minutes, POODR Notes: Acquiring Behavior Through Inheritance (Chapter 6), Sometimes simple things go wrong and are deeply frustrating. Maybe your awful code isnt just a View concern. We can solve it easily in the Model. Fixing this Rails problem is straightforward (could be given to a junior developer). It was a great time to discover what I like to do and what not. Additional Reading: The Bastard's Book of Ruby. The code looks more procedural than object oriented and it has some duplications. Weve already awarded over 1500 Learn Enough Scholarships to a wide variety of recipients, including students, people between jobs, and residents of countries with unfavorable exchange rates. Ive worked and Im still working on web application projects. See https://github.com/drapergem/draper for good examples. Those tools are helpful to see where problem in code can be. (With rspec you can identify test by line number.). I have to say that project_list_item is overhead, there is no reason to hide such simple HTML snippet into helper. Now when code is more readable, I can start changing the logic to simplify it. In your own Rails refactoring process, feel free to skip a few steps down the pipeline if you are confident in doing so (e.g., jump from View to Controller, or Controller to Model). various types of statistics and put it where it belongs by adding the following to Motif of Living Water in Slavic Tradition, delegating business logic to keep executables short, eliminating redundancy in Cucumber scenarios, using the facets gem to eliminate Ruby indent spasms, implementing the Single Responsibility Principle. And I look for answers on how to write good code. I dont know if you noticed this, but everywhere we put as argument array. The problem is straightforward and one that weve all been trained to solve multiple times. Down the cachinghole: adventures in'HTTP caching and Free mentoring for early career developers. Automated tests facilitate aggressive refactoring. Clearly, we are still making the mistake of a Model query in a View, but at least when a maintainer comes in later and sees my horrible partial, they will have a straightforward way of tackling that Rails code problem in particular. Along the way you gained additional practice with the Test-Code-Refactor I feel like a n00b again, and it feels good. Sometimes, bad code is easier to refactor into beautiful code than a poorly thought out solution implemented under a time-crunch. Its generally intended that you progress sequentially, but theres no right way or right order to encounter these topics. refactoring Im going to solve it The Wrong Way and demonstrate how to refactor my solution into its appropriate areas. I wish I could help every single person who might read this post refactor their own code. the source of its numbers nor what is done with the results. Extract Method refactoring Woman, programmer, mentor, speaker, photographer and dancer with passion. The idea is you do something like: Premium. There was an error submitting your subscription. Each example contains: Two code sample files, before and after refactoring; Before you start refactoring, it's important to grasp the basic but most More than 2500 pages of book content and 53 hours of video that teach you to code from total beginner up to professional-grade web development. Its most likely youll be reading (and updating) code that someone else wrote. I respect that. Ive already added a JUnit test stub to get you started quickly. in bin/statowl to a separate You could convince me I have the order exactly backwards. plain text, HTML, XML, or JSON. I removed it (remove all content inside). In Eclipse, use Help->Install new software with to install has no knowledge of what the hash actually contains: Still green? Bye! So number 0-3 represents 2 with all colors, 4-7 represents 3 and so on. According to the Single Responsibility Principle, every class should When you do this yourself, dont worry about it to much. Control your refactoring urges for now, however. Full online version of the tutorial, embedded streaming videos for all sections, exercises with editable answers, progress tracking, and membership in the Learn Enough Society (community exercise answers, private chat group).