Category Archives: software design

Putting the ‘O’ in SOLID


We
covered the Open/Close principle in a recent lab, and it prompted a desire to
cover some of the SOLID principles. I have determined however, that the length
of this blog is short enough that I should dedicate it to a single principle at
a time, beginning with the aforementioned Open/Close principle.

              This particular object-oriented
principle was outlined by Bertrand Meyer and states:


“…entities should be open for extension, but closed for modification.”


              This of course, is a complex way
of expressing a simple guideline for software development; which is that new
functionality should be able to added without having to radically change existing
code. The operative word, extension, is illustrative. If your code was a home,
and you wanted to add more square-footage (read: functionality), you shouldn’t
need to knock all the walls, or the whole thing, down to add a bathroom.

              In the blog chosen, the author summarizes
a talk he gave about the very subject. In it, he provides an example of a program
he is developing for a company that calculates the total area of a set of rectangles.
As the customer requests more and more shapes be added to the calculator, the original
code changes drastically and gets longer and longer. This modification is opposed
to this principle. In opposition, creating a Shape class that contains many children
of different specific shapes – each with their own area function – with the
ability to add more, eliminates constant modification of the main class, and
allows for constant extensionability in the form of new shapes.

              To say simply that code should be
modular is unhelpful, as it is broad and the general definition of so many more
good coding practices. Our class and homework provide another perfect example.
Why should we have to constantly Override and rewrite portions of a superclass’
methods in each of its child classes to achieve proper functionality. Instead, in
making a Quack/Fly Behavior interface we have established a broad mold that
many new behaviors can be built off of; access to all of which is then granted
by the relationship to the single respective behavior interface.

              Therefore, the ability of code to be
extended with new functionalities, using a single reference – in this case the behaviors,
or shapes – instead of needing to rewrite or overwrite code is what is meant by
extension; while keeping the existing code from needing constant revisions, is being
closed for modification. Like the house example earlier, you should constantly be
building out, not renovating what exists already.


Sources:

A
simple example of the Open/Closed Principle

From the blog CS@Worcester – Press Here for Worms by wurmpress and used with permission of the author. All other rights reserved by the author.

Refactoring: Spring Cleaning for Code

Depending upon the subject, some of us are lucky to finish a functioning project so the thought of improving code after the fact – especially if there’s a new project due soon – is a distant one. However, they may be tricked into refactoring their code if asked when you say the magic words: “Refactoring is not rewriting code”. The definition, as defined by its creator is:


“a change [or changes] made to the
internal structure of software to make it easier to understand and cheaper to
modify without changing observable behavior.”


In
reality, the process may involve:

  • new
    code, but it must not change the behavior of the original code;
  • ensuring
    the system works before and after each refactor, including original unit tests;
  • creating
    unit tests to verify our refactoring has not changed system behavior;
  • changes
    that individually are minute, but combined lead to a healthier program;
  • eliminating
    duplicate code, potentially changing variable names, and more.

It is not
simply cleaning up code, but rather reorganizing it in order to make it easier
to trace and understand, as well as add functionality to in the future.

              For our purposes, this may be a very
important concept to learn but it may be some time before we get to implement
it, unless we’re coding or maintaining an entire program for our capstone; however,
it is important to understand when to do so. According to my sources, the best
time to do so is before you add new features to an existing program, or right
after you’ve already shipped it. For the former, it makes these new features much
easier to add when the program is much more readable and makes the program better
for having made the changes. As for the latter, it makes a lot of sense to
snoop around for ways to reorganize code after you’ve spent so much time on it,
and in a mad dash to finish it towards the end no doubt. Years’ worth of work
is no doubt going to have some inconsistencies that fell through the cracks in
the course of development.

              As for implementing these changes, there are several methods, including Red-Green-Refactor, Abstraction, Simplifying Methods, as well as many others we won’t cover. In R-G-R, red means stop and determine what to develop – usually with a new test that fails, getting this new development to pass tests (green), and finally refactoring to optimize. Abstraction is used to address duplicate code and can be done by restructuring hierarchies using the Pull-Up [pulling up code into a superclass to be shared more effectively] or Push-Down [pushing down code to more subclasses from a superclass] method. Finally, Simplifying Methods is an effort to simplify older code by consolidation and reducing interclass complexity. Hopefully this helps develop an understand of refactoring, in fact, I had to do quite a lot of refactoring to this blog to get it down to size!


Sources:

Refactoring – Martin Fowler
Refactoring – Agile Alliance
Code Refactoring Best Practices: When (and When Not) to Do It

From the blog CS@Worcester – Press Here for Worms by wurmpress and used with permission of the author. All other rights reserved by the author.

Thinkin ‘bout KISS‘n you


KISS
(Keep it Simple, Stupid) is potentially one of the most culturally pervasive concepts
used in Computer Science, the other being maybe blockchain – the difference of
course is that people actually understand what KISS is, everyone who says they
understand blockchain is lying. Of course, KISS did not originate in Computer
Science, and instead was popularized at Lockheed Skunk Works by noted
tangential war criminal and engineer Kelly Johnson. While it may be difficult and
seemingly sacrilegious to try to explain something so self-explanatory that is
what I hope to do, flying in the face of the concept of simplicity to stretch
four words into four hundred.

Credit: csiaexchange

              It begins with, put kindly, making
distinctions about the semantics of the scant few words in this phrase; put
more bluntly, being pedantic. This examination is important, and the linked
article does a great job of highlighting first the distinctions between ‘simple’
and ‘easy’, which could be mistaken as synonyms, and contrasts it with ‘complex’.
His conclusion is this, a simple system is defined by what it is not, which is one
with too many parts which are interconnected – with the latter being worse in
software development.

              This all sounds wonderful on paper,
and about the same on a computer screen, but sometimes complexity is
inevitable. So, it is advised that you make things as simple as possible, until
you can’t, at which point you are vigilant in handling that necessary
complexity. For instance, I could try all sorts of methods to navigate a 2D
array in some mock-up code, but I don’t need to introduce recursion or anything
outrageous to shorten a method body if a simple nested loop will do.

              This idea of simplifying through pruning
code is expressed in the next sections of this post, stressing the importance
of cleaning up dead or underutilized code so that no resources are wasted maintaining
or reintegrating useless code. Additionally, YAGNI (yay more acronyms) states
more or less the same thing, encouraging programmers to implement the essentials,
that will actually be presently utilized, and skip the bells, whistles, and
maybes. Code with bunches of maybe methods require time and resources to
maintain and if they aren’t actively being utilized, then they’re a waste of
both.

              From here on, the blog introduces
many more concepts that are possible to cover in just this blog post – although
I do hope to mention Lasagna Architecture in another post sometime later. Instead,
I think it is time to bring this post to a close. What is the take-away then?
Well its exactly what you thought it was from the first line. In conclusion, it
may be appealing to get a jump on features you may want to implement in the future,
but it is best to keep things as simple as possible and/or only as complex as
needed but no more.


Sources

KISS Principle Explained
KISS, A Design Principle

From the blog CS@Worcester – Press Here for Worms by wurmpress and used with permission of the author. All other rights reserved by the author.

WSU x AMPATH || Sprint 5 Retrospective

Sams Ships (14)Over the past two weeks, my team continued to discuss what we are working on as usual. We have come to the conclusion that we will add our Search Bar component once there are updates and more of a base to work off of. This was concluded after we realized that the process would be much more efficient. The parameters and details on the search bar would be harder to figure out without making up a base anyways.

Some advice for others who may be working on the same thing would be to try and collaborate or discuss potential orders between groups if one thing may depend on another. That would make it much simpler from the start if possible so there aren’t any clashes or time wasted on doing extra work that could have just been done by one group or team.

In the meantime, I did a little more research on the AMPATH system out of curiosity since we are going to be building onto their work. I found out that there are 500+ care sites in Kenya! It is interesting to think about the potential impact our work may make on how AMPATH carries out their process. Their initiative reminds me of what Enactus at Worcester State strives for when they work on projects to help people or organizations in the community “sustain their own success, connect them with universal health insurance, train next generation medical professionals, and research new breakthroughs and best practices.” Being able to help a healthcare organization is pretty meaningful, especially as a project through my capstone.

A way to tie our 348 course (Software Process Management) with our 448 (Capstone) course would be through now being able to use Travis CI and Heroku. It was interesting being able to experience using these in class and help our peers use it and now be able to use them in our capstone. I think the practice we got was nice because I found that my peers and I were more comfortable with following steps that were written out and explained to us instead of just “going for it.” I have also noticed that our 348 course helped us pay more attention to how we interact with others, which is very useful for the future when we will be working in teams of developers to create or update new technologies. One more thing which I found useful was seeing Travis CI load, and the race against time when it came to classmates pushing code at the same time; it made me push myself to be a little faster while at the same time not be sloppy about what I was putting into my code.

Overall, we discussed what we will do in these coming weeks as the semester comes to a close. The project we are planning on presenting will feature a search bar which we plan to implement by then. I am excited to see what we end up with in terms of helping AMPATH and their healthcare system!

 

 

From the blog CS@Worcester by samanthatran and used with permission of the author. All other rights reserved by the author.

Craft Over Art || S.S. 8

Sams Ships (10)As we have a few weeks left in the semester, I wanted to discuss the more creative apprenticeship patterns. This time I’m going to describe Craft Over Art, which is basically when a solution to a client’s problem can be solved with something that could work…or we could take it and go above and beyond. It’s being more innovative than just settling for a solution just to have something.

I found that the pattern is interesting because it emphasized the importance of how the things built for customers can still be beautiful but must always be useful. If it strays away from being useful, then it no longer counts as the craft.

I also found it to be thought-provoking because it brought up how people are truly in charge of how a problem gets solved. No one can force you to code something a certain way if they do not know a way to solve it on their own, which is why your role exists in the first place.

The pattern has caused me to change the way I think about my intended profession because your work can still reflect you in terms of creativity. As a person, I think I am more on the creative side and incorporating more ideas into creating something for people sounds pretty cool. If I had to follow a super rigorous structure, I may feel limited in what I can do to produce work that makes me happier.

The one thing I have to disagree with in the pattern is the part where it mentions that someone is suddenly no longer “part of the craft” if they deviate a little further. Who sets these boundaries? I do not want people to feel like they are not “enough” to be considered a real craftsman or whichever term it is referred it as just because they were being extra.

Overall, I appreciated the action section which encouraged people to reflect on what projects they worked on or situations they may have found themselves in where they chose creativity over usefulness. At the moments where I have personally done so, I had felt more proud of my work, because I knew it was uniquely mine.

From the blog CS@Worcester by samanthatran and used with permission of the author. All other rights reserved by the author.

Do You Hate Your Computer Too?

Sams Ships (3)Apparently doctors hate their computers, according to an article titled Why Doctors Hate Their Computers by Atul Gawande. Gawande started out the article by mentioning Epic, a company a lot of people know of because it is a leading provider of software for the healthcare industry. It’s funny because just the other day, a classmate who will not be named groaned when he heard Epic being mentioned by someone, as he works in a healthcare center.

I found the reading was interesting because I have no intentions of becoming a medical doctor one day but was able to hear about how it is being one while interacting with technology that exists today.

It seems like the tension of logging everything caused the system to make doctors’ lives harder instead of easier; this was noticeable when Sadoughi was talking about how she had to look over all notes from different doctors including herself per patient. Instead of being able to just see what is going on right away; it would take up time to gather all information and even then it was not always helpful because some notes were different than others and became dated. And then work-life balance had to be thrown off a little because people had to spend extra time, up to hours after-hours to catch up with the system and review things from the day.

The real customer for the system seemed to be patients because they have some benefits from using the system like logging when to take medications or see how they are doing. Doctors are also able to monitor how they are doing and communicate with them by being pinged.

The lessons from this system do not only apply to Electronic Medical Record systems; they also apply to working in life because burnout can happen to anyone in the workforce. I thought it was interesting how one of the ways doctors were trying to save time and prevent burnout from technology was by hiring in-hospital scribes or even virtual scribes when necessary.

The reading has caused me to changing the way I think I will work based on if I ever end up creating software that affects people’s healthcare by considering how much time it takes to interact with it, no matter how “cool” or “innovative” it may be. In terms of the topic itself, the reading has caused me to think more about software that has altered people’s professions as a whole; which I thought of before but never this deeply.

I do not disagree with anything in the reading for now as I do not personally know what it is like to work in a profession that is not traditionally non-technical and then gets transformed into something that relies on it.

 

From the blog CS@Worcester by samanthatran and used with permission of the author. All other rights reserved by the author.

Expose Your Ignorance|| Sam’s Ships S.S.2

Sams Ships (1)For this next installment of the Apprenticeship Series, I wanted to discuss Expose Your Ignorance. This apprenticeship pattern involves being more direct with people to have the faster route on the road to journeyman instead of protecting one’s pride to find other ways to obtain the knowledge they are seeking. When someone exposes their ignorance, they will be able to learn more quickly instead of trying to appear like they are capable.

Based on what I have learned of this pattern so far, my reaction is that it was useful seeing examples of how this happens in real life for people. To me, this was something I thought of before without putting it into a framework of sorts. I found that this was interesting because of the way they explained it saying, “One of the most important traits that a craftsman can possess is the ability to learn, identifying an area of ignorance and working to reduce it.” It shows how ignorance does not necessarily mean they are at fault of something, it just means they are willing to work to move past it.

Taking this as a lesson to think about, the way I work will be pretty much the same. I once almost made a task over-complicated because I wanted to find my own way to work on it instead of just asking another developer for their opinion on whether I was doing something correctly. After deciding to ask for help thought, we figured out that there was a much more simple way of going about it instead of changing a whole system of developing a certain feature. Due to this, I have gained more confidence to ask people when I am uncertain about something because in the end it would save a lot more time and avoid confusion.

I did not disagree with anything brought up in the pattern so far because I believe people should be able to communicate when they are not confident about something or at least ask for clarification. After some thinking, I realized I’ve never expected anyone to know everything so why should I feel like other people should expect the same from me?

From the blog CS@Worcester by samanthatran and used with permission of the author. All other rights reserved by the author.

The White Belt || Sam’s Ships S.S.1

Sams Ships.png

So you either want to or have already been an apprentice for software development huh? I just read the section on the apprenticeship pattern for The White Belt and it was a nice beginning to approach what we are doing. It reminds me of a quote: “In any given moment we have two options: to step forward into growth or back into safety.” This is us stepping out of our comfort zone as we approach real-life situations and try to help them by starting our journey into development.

A summary of the pattern would be after some time of developing skills, someone may feel that their growth has plateau-d, however there still remains confidence in their abilities to do something. I found that this was interesting because as someone approaching a career where I will be a life-long learner of technology and ways to develop it, I never considered getting stuck or feeling like I was not getting somewhere.

Based on what I have learned about the pattern, I think it will change the way I work based on their advice to set things we have previously learned aside in order to “unlearn what we have learned.” I like the idea of approaching something that is new to be able to fully appreciate it.

I could relate to the situation they describe about sacrificing productivity in order to improve our skills. From on-boarding as a junior developer, it was a different experience trying to do self-learning while getting assigned tasks to work on at the same time. It was interesting trying to find a good divide between learning something while trying to develop things compared to using internet references.

I agree with how they mentioned not basing everything you learn in other languages based on comparing it to a base language that you know. This made me realize how I have been doing this for a while; I sometimes forget that not everyone knows Java or a language that would seem “universal.” It would help take away the stress of thinking in a certain language’s syntax or process; allowing people to just code something that would work more efficiently and effectively.

Overall, I would say that this pattern is nice to hear about in the beginning so people can approach it in a way that allows them to learn things with a fresh start to programming. I also just liked how they called it The White Belt so people can level up.

From the blog CS@Worcester by samanthatran and used with permission of the author. All other rights reserved by the author.

Adapt or Git Left Behind?

CS SERIES (15)As my last fall semester comes to a close, I wanted to write about an article on something pretty interesting I learned about in my software construction and design course.

On Stackify, Thorben Janssen wrote Design Patterns Explained–Adapter Pattern (with code examples). Overall, this article re-instilled how design patterns make it easier to write more well-structured and maintainable code.

I found it useful to see how Janssen discussed the two different versions of the class adapter; the class adapter pattern (which implements the adapter using inheritance) and the object adapter pattern (which uses composition to reference an instance of the wrapped class within it).

Similar to how we learned the concept in class, something I appreciated is the “real-life” example or comparison used to describe the physical adapters we use when traveling. When we are traveling and do not have compatible power sockets, we must find a way to be able to charge our use our devices without having to change the whole make of it. A way of doing so is by using adapters; which does not change the overall product or device, it just allows you to be able to plug it in.

An situational example that I can think of when explaining adapters is if you have ever been zip-lining or done a ropes course (like Go Ape) where you are attached to a harness. When you are transferring from one line to another, you can use a metal contraption which helps guide you while connecting and disconnecting from paths. That metal contraption serves as an adapter, not changing what you are but allowing you to use something.

I agree with what message Janssen is trying to express about how great design patterns are (the adapter pattern specifically) when it comes to writing code. His content allowed me to think about real life situations in code form when he introduced the basic and premium coffee machines to brew coffee using the adapter pattern. One of the best ways of learning concepts, in my opinion, is to compare it to a real-life situation and then show people visualizations to help them better understand what you are trying to explain and the article did both.


Article: https://stackify.com/design-patterns-explained-adapter-pattern-with-code-examples/

From the blog CS@Worcester by samanthatran and used with permission of the author. All other rights reserved by the author.

Top 5oftware Architecture

CS SERIES (13)When using architecture patterns, how will you know which one to choose? Peter Wayner, an independent author for TechBeacon takes five architectures that the majority of programs today use and broke them down into their strengths and weaknesses. Through this, it seems like he is hoping to guide users to selecting the most effective software architecture pattern for their needs.

If this article does not clear up enough information, Wayner also brings up a book, Software Architecture Patterns by Mark Richards, which focuses further on architectures commonly used to organize software systems.

The fives types discussed in the article are:

  • Layered (n-tier) architecture
  • Event-driven architecture
  • Microkernel architecture
  • Microservices architecture
  • Space-based architecture

The one I found most interesting is space-based architecture because at first when I thought of space, I was thinking of the other kind. The one with the sun and the stars and the moon. But then I realized–what does that have anything to do with software architecture? Space-based architecture is listed as “best for high-volume data like click streams and user logs” and I think this one is pretty important, especially during times like Black Friday and Cyber Monday. I personally experienced the frustration of not being able to access a site (adidas) due to high volume and it really does not help a business.

Another architecture I found thought-provoking is micro-services architecture because of the way Wayner introduced the concept, “[s]oftware can be like a baby elephant: It is cute and fun when it’s little, but once it gets big, it is difficult to steer and resistant to change.” The author providing an example of this made me think about how a site with so many users and things happening at once actually just had many different separate services but they were put together as one. I was a little surprised to think of Netflix in that way after all the times I’ve used it but it makes much more sense now.

Overall, I found all of the information pretty useful and clear to understand as Wayner described what they were and then listed the caveats and what they were best for. I would recommend using this as a reference or quick review of common software architecture designs if someone needs it.


Article: https://techbeacon.com/top-5-software-architecture-patterns-how-make-right-choice

From the blog CS@Worcester by samanthatran and used with permission of the author. All other rights reserved by the author.