Software Development: An Open Source Approach <-> RMH Homebase (Developing the Domain Classes)

For this post I will be going through Chapter 6 of Software Development: An Open Source Approach and reflecting upon my experience with some of the exercises at the end of the chapter. All of the exercises focus on dealing with the open source software RMH Homebase (which I have mentioned in posts in the past).

The previous blog post in which I talked about the installation and usage of RMH Homebase can be found here.

The RMH Homebase release 1.5 code base can be downloaded from myopensoftware.org/textbook

Unfortunately, all the work I did on my previous post is for naught for the purposes of doing these exercises since I am on a different computer. So let's run through some commands and dependencies with which I had to deal:

% sudo apt-get install mysql-client mysql-server
This command didn't work as I had hoped because it kept complaining about out-of-date dependencies and missing dependencies. And these errors kept continuing.

% sudo apt-get install mysql-server-5.5 mysql-client-5.5
led to
% sudo apt-get install libdbd-mysql-perl
led to
% libmysqlclient18
which ultimately led to an error with glusterfs-server, which is something, I believe, extremely specific to my lab computer.

Experience-wise, it is good that I can note what is going on. Practicality-wise, this is frustrating because I do not want to tinker with the cluster as there are a lot of projects that are relying on the cluster not being tinkered with (including my own). So while this was valuable, I will continue this on a different computer at a later point. Also, the gluster error perpetuated for every package I wanted to install (apache, php, etc.)

More commands:
% sudo apt-get install apache2
% sudo apt-get install php5
% sudo apt-get install phpmyadmin

For reference, an easier way to get all of the MySQL stuff installed can be done through:
% sudo apt-get install mysql-client-core-5.5 mysql-server-core-5.5

Everything that these commands install and do can be found in my older blog post I mentioned earlier.

The exercises are very basic, in nature. Defining new functions to set and retrieve the value of the variables $employer, $contact_person, and $contact_phone.

So, pretty much. Encapsulate the Person class with getters and setters so someone can say "get_employer()" or "set_employer($newEmployer)". So there's not really any work here rather than making getters and setters for all 3 of the features.

Example:
function set_employer($newEmployer){
     $this->employer = $newEmployer;
}
function get_employer(){
    return $this->employer;
}

The next step is to create a more well-defined constructor. This goes as follows:

function __construct($f, $1, $a, $c, $s, $z, $p1, $p2, $e, $t, $status, $employer, $contact, $contact_phone){
     $this->first_name = $f;
     $this->last_name = $l;
     .
     .
     .
}

It's obvious that you would just typical assignment in this constructor like I started to outline. When doing the password field you would probably want to throw in your favorite flavor of encryption so you are not handling raw passwords because that's a security no-no.

The next question pretty much asks you to rewrite the set_status function because currently the $value that is passed in is never checked to be valid (which it can be "active" or "inactive"). Currently, if something else is passed in (let's say "cheese") then someone's status could be set to "cheese" rather than actually checking if there is a problem. So let's rewrite the function below:

function set_status($value){
     if ($value == "active" or $value == "inactive"){
          $this->status = $value
     }
     else{
          echo "Your input for set_status was invalid. active and inactive are the only valid options."
     }
}

So now the user knows if they picked a wrong value for set_status and status does not get changed if an invalid input is put in.

The last exercise is to refactor the Person class (where we've been working this entire time) to have removed all the mutators that aren't called from anywhere in the code base. This can be done by deleting or commenting out (commenting out would be preferable in my eyes) unused mutators.

Music listened to while blogging: Childish Gambino