What is the best way to represent configuration options internally? - php

So, I am looking at a number of ways to store my configuration data. I believe I've narrowed it down to 3 ways:
Just a simple variable
$config = array(
"database" => array(
"host" => "localhost",
"user" => "root",
"pass" => "",
"database" => "test"
)
);
echo $config['database']['host'];
I think that this is just too mutable, where as the configuration options shouldn't be able to be changed.
A Modified Standard Class
class stdDataClass {
// Holds the Data in a Private Array, so it cannot be changed afterwards.
private $data = array();
public function __construct($data)
{
// ......
$this->data = $data;
// .....
}
// Returns the Requested Key
public function __get($key)
{
return $this->data[$key];
}
// Throws an Error as you cannot change the data.
public function __set($key, $value)
{
throw new Exception("Tried to Set Static Variable");
}
}
$config = new stdStaticClass($config_options);
echo $config->database['host'];
Basically, all it does is encapsulates the above array into an object, and makes sure that the object can not be changed.
Or a Static Class
class AppConfig{
public static function getDatabaseInfo()
{
return array(
"host" => "localhost",
"user" => "root",
"pass" => "",
"database" => "test"
);
}
// .. etc ...
}
$config = AppConfig::getDatabaseInfo();
echo $config['host'];
This provides the ultimate immutability, but it also means that I would have to go in and manually edit the class whenever I wanted to change the data.
Which of the above do you think would be best to store configuration options in? Or is there a better way?

Of those 3 options, a static method is probably the best.
Really, though, "the best" is ultimately about what's easiest and most consistent for you to use. If the rest of your app isn't using any OO code then you might as well go with option #1. If you are ultimately wanting to write a whole db abstraction layer, option #2.
Without knowing something more about what your goals are and what the rest of your app looks like, it's kind of like asking someone what the best motor vehicle is -- it's a different answer depending on whether you're looking for a sports car, a cargo truck, or a motorcycle.

I'd go with whats behind door #3.
It looks easier to read and understand than #2, and seems to meet your needs better than #1.

Take a look at this question for ideas on storing the config data in a separate file:
Fastest way to store easily editable config data in PHP?
I'd use method #2 pulling the config data as an array from an external file.

The best way is that which fits your application best.
For a small app, it might be totally sufficient to use an array, even it is mutable. If no one is there to modify it except you, it doesn't have to be immutable.
The second approach is very flexible. It encapsulates data, but does not know anything about it. You can pass it around freely and consuming classes can take from it what they need. It is generic enough to be reused and it does not couple the config class to the concrete application. You could also use an interface with this or similar classes to allow for type hints in your method signatures to indicate a Config is required. Just don't name it stdDataClass, but name it by it's role: Config.
Your third solution is very concrete. It hardcodes a lot of assumptions about what your application requires into the class and it also makes it the responsibility of the class to know and provide this data through getters and setters. Depending on the amount of components requiring configuration, you might end up with a lot of specific getters. Chances are pretty good you will have to rewrite the entire thing for your next app, just because your next app has different components.
I'd go with the second approach. Also, have a look at Zend_Config, as it meets all your requirements already and let's you init the Config object from XML, Ini and plain arrays.

Related

Is it a good practice to define expectation in dataProvider

quick example of dataProvider:
return [
['180d-1pc', '6m-1pc'],
]
and test:
public function test_convert($title, $expected)
{
$uut = new Converter();
$this->assertEquals($expected, $uut->convertDayTitle($title));
}
(simply put: test if we convert 180d(days) to 6m(months))
as you can see - in data provider there are input data defined and also an expected output.
This works fine in many cases, but I keep having this feeling that maybe it's not the best idea. So I'm wondering if could be considered bad practice. If so - when I will see it was a bad idea to do it?
One example is, when you would like to use the same dataProvider in two tests - should you define two expected values and use one of them?
Quick example (I just made that up, so don't pay attention that I make product object just from title ;)):
public function test_gets_discount_when_licence_period_longer_than_1year($title, $expectedTitle, $expectedDiscount) {
$prod = new Product($title);
$this->assertEquals($expectedDiscount, $product->hasDiscount();
}
How to make this more elegant?
What you're doing is totally fine. Data providers can, and should, include the expected test result.
About the issue of reusing the same dataProvider for 2 tests, and only using some fields: I'd say that if the fields are related (i.e. they are properties of the same object), it can be acceptable.
If you feel the dataProvider is getting too big and complex because 2 tests must use data from it, just create 2 separate dataProviders, and use another private common method for building the common data.

Call method from class of unknown name

The title may be confusing, but I'm not sure how to word it otherwise. So I want to be able to initialize a class and call methods from it without knowing the class name before getting it from an array.
What I want to do
$modules = array(
'Forums' => array(
'class'=>'Forums',
'classVar'=>'forum'
)
);
foreach($modules as $name => $module) if ($module['enabled']) {
require_once('include/scripts/'.$module['link']);
$$module['classVar'] = new $module['class'];
$$module['classVar'] = $module['classVar'];
global $$module['classVar'];
}
However, I know that this is a roundabout way to accomplish this, and I need to know if there's an easier way, and if this is even logical.
The reason I want to do this is because what I'm working on will be able to accept modules, and I need to be able to get all of the stats from the modules and display them in the main admin panel, but there's no way to know if a module is enabled and running if I didn't create it. For instance, if someone created module.php that tracked how many times someone clicked a specific link, the software wouldn't natively know about it, and I need it to be able to get stats from it.
Hmm, you might be interested in the Singleton design pattern (http://en.wikipedia.org/wiki/Singleton_pattern and http://www.phptherightway.com/pages/Design-Patterns.html).
In this case you'd have a list of classes in your configuration array and call "getInstance()" when you actually want to do something with the actual module.
Also, have a look at the Factory pattern, it might be useful for your purposes as well.

Registering a new user in the Model layer. Am I doing it right?

I have been reading up on DDD a lot over the last few days and could not find one solid example of how someone would go about simply registering a user on their site so after lots of reading I have stuck this together and I would like your feedback on it because I am sure it is far from perfect, it might even be completely wrong but here it goes:
RegisterController
$userMapper = $this->dataMapperFactory->build('user');
if($userMapper->fetchByUsername($username) !== NULL) {
// Error: The chosen username already exists
}
else {
if($userMapper->fetchByEmail($email) !== NULL) {
// Error: The email address already exists
}
else {
$userDO = $this->domainObjectFactory->build('user');
// Set the properties of the $userDO object here with the ones
// from the registration form
// Insert the new user into the database
$userMapper->save($userDO);
}
}
I have done all the form validation with my own FormValidation class so when I add the properties to the $userDO object they are all 100% ready to be inserted into the database (correct length, type, format, ranges etc) so how does the code look to you?
I think I am on the right track and I would really appreciate any tips on how to improve my code.
Also, the way I am checking if the username they chose has already been taken, is there a better way to do that? Instead of having to create an object each time to check? Like the old way I used to do it with a simple:
SELECt COUNT(*) FROM users WHERE username = 'john'
Thanks.
Some theory-related "blah":
As you might be aware, the core concept of MVC and MVC-inspired design patterns is the SoC. It dictates that you divide these patterns in to major layers: presentation layer and domain model layer.
In this case it is significant, because you current structure of controller contains application logic (the interaction domain logic entities and storage abstractions), whereas a controller should be only responsible for altering state of model layer (and sometimes - the current view) based on user input.
You end up violating bot the above mentioned SoC and also SRP.
Note: in context of web based MVC variations the "user" is a web browser, not the person sitting behind it.
Instead you should encapsulate the application logic in services (as #Gordon mentioned). In a fully realized model layer the different services become something like a public-ish API through which the presentation layer interacts with model.
Though, unlink Gordon, I would recommend your service to be a bit broader. In case of user registration, I would make it a part of CommunityService or maybe MembershipService. A structure that handles all the aspects of the user account management as far as the model layer is concerned.
The code bits:
One way for using in controller would look something like:
public function postUser( $request )
{
$community = $this->serviceFactory->build('Community');
$community->addUser( $request->getParameter('username'),
$request->getParameter('password'),
$request->getParameter('repeated_password'),
$request->getParameter('email') );
}
While this is a valid way, you might already notice an possible problem. Even when user registration need only the minimum of data, the amount of parameters that you end up passing to the service makes it hard to use.
Passing the $request on to service is not a valid improvement. You would just end up violating Law of Demeter. Instead i would recommend something like:
$keys = ['username', 'password', 'repeated_password', 'email'];
$community->addUser( $request->getParameters( $keys ) );
Where the getParameters() method is implemented similar to:
public function getParameters( $keys )
{
$response = [];
foreach( $keys as $parameter )
{
$response[ $parameter ] = $this->getParameter( $parameter );
}
return $response;
}
Domain logic and validation
You mentioned, that some FormValidation class, that you are using to make sure, that your instance of User domain object receives proper values. Actually the data validation is one of the domain object's responsibilities. You still might use a separate validation class, to avoid code duplication, but that would be a dependency, which is injected by domain object's factory to share between instances.
Note: in my personal experience, the duplication for validation is quite rare for anything but the null-checks. Each of complicated validation rule-sets are targeted at fields of one specific domain object. That, in my opinion, makes a validation class quite redundant ... unless you expect to share same validation class between multiple projects.
The code-flow usually is such that, when you need to store the data from domain object, you check if it has not acquired an error state, and if there is an error, you actually dump it in session, for a retrieval after redirect.
if ( $user->isValid() )
{
$sqlMapper->store( $user );
}
else
{
$sessionMapper->storeUser();
}
In this use-case pre-validated input ends up actually being harmful.

Does this function have too many parameters?

In the end, I got this function. I don't know whether it's normal or not.
function user_registration($user_name, $user_email, $user_pass, $address,
$city, $postalcode, $country, $phone, $mobilephone)
How and why can I improve this?
You could either pass an array with all variables packed nicely together, or just make a "User" class and add all properties via setters and do the validation in the end with a dedicated method:
class User {
public function setName($name) {
$this->name = $name;
}
[...]
public function register() {
//Validate input
if (empty($this->name))
$this->errors[] = "ERROR, Username must not be emtpy";
//Add the user to the database
//Your SQL query
return empty($this->errors);
}
}
$user = new User();
$user->setName("Peter");
$success = $user->register();
if (!$success)
echo "ERRORS OCCURED: ".print_r($user->errors, true);
A solution would be to only have one parameter, that can contain several pieces of data -- like an array.
Your function could be defined this way :
function user_registration(array $data) {
// work with $data['name']
// and $data['email']
// ...
}
And you'd call it like this :
user_registration(array(
'name' => 'blah',
'email' => 'test#example.com',
'pass' => '123456',
// and so on
));
Nice things are :
You can add / remove "parameters" easily
The "parameters" can be passed in any order you want
Not so bad things are :
No hint while typing in your IDE
No documentation (like phpDoc)
I personally don't think it has too many parameters. From looking at the functions definition it is clear what you require as input which wouldn't be so obvious if called with an array.
"If it aint broke don't fix it!"
When you look at your argument names, you cannot but notice that they can be grouped into three different groups:
User Data: $user_name, $user_pass
Address Data: $address, $city, $postalcode, $country
Contact Data: $user_email, $phone, $mobilephone
Consequently, you could apply Introduce Parameter Object:
Often you see a particular group of parameters that tend to be passed together. Several methods may use this group, either on one class or in several classes. Such a group of classes is a data clump and can be replaced with an object that carries all of this data. It is worthwhile to turn these parameters into objects just to group the data together. This refactoring is useful because it reduces the size of the parameter lists, and long parameter lists are hard to understand. The defined accessors on the new object also make the code more consistent, which again makes it easier to understand and modify.
If you dont want to do OOP you could group the arguments into arrays as well but you'll lose all the type benefits then. I will just assume you don't mind using objects. So, after applying the Refactoring you'll end up with
function user_registration(User $user, Address $address, Contact $contact)
Looking at that parameter list should make you notice that Address and Contact likely belong to User in the first place, so you could consider changing the function signature to just
function user_registration(User $user)
and then call it like this:
$user = new User('johndoe', 'secretsauce');
$user->setAddress(new Address('Doe Street', 'Doe Town', 12345, 'Neverland'));
$user->setContact('jdoe#example.com', '+123 12345', '+123 54321');
user_registration($user);
We could probably make username and password into a Credentials object as well and then just do
user_registration(new User($credentials, $address, $contact));
By requiring the data in the ctor we make sure newly registered users do have all these information. We could argue whether we need Address and Contact for registering users though, so Setter injection might be good enough here:
$user = new User(new Credentials('johndoe', 'secretsauce'));
$user->setAddress(new Address('Doe Street', 'Doe Town', 12345, 'Neverland'));
$user->setContact(new Contact('jdoe#example.com', '+123 12345', '+123 54321'));
user_registration($user);
However, user_registration as a separate function in global scope is misplaced. By GRASP's Information Expert principle, methods should be on the objects that have the most information to fulfill the responsibility. This improves Cohesion and reduces Coupling. In other words:
$user = new User($credentials);
$user->setAddress($address);
$user->setContact($contact);
$user->register();
One problem with the User class now is that it contains the password. The password is only ever needed to authenticate the user against the authentication service. We could argue about the username, but the password definitely should not be part of the User object at all. So you should do something like
$user = new User;
$user->setAddress($address);
$user->setContact($contact);
$user->register($credentials);
and when register() is called, it will only use the credentials to delegate insertion of a new user into the user storage. But it will not retain them in the actual User instance.
Finally, you might want to add a Simple Factory or Builder pattern to encapsulate the creation of the User to simplify the aggregation of the various instances. Or you might want to introduce a Repository pattern and move the register() method there. This is beyond scope for this question though.
As a general rule of thumb (not as a steadfast rule), anytime you have to ask "Does this function have too many parameters?" -- the answer is yes. Your intuition is telling you something that your brain just hasn't yet been able to work out.
In this particular case, the first thing that comes to mind is that your user cred.s should be checked first (does the username already exist? is the pw complex enough) and your user details should be added separately, probably using an object or array.
One way is to pass an array as parameter to this function and put all info in that array:
function user_registration(array $user_info)
{
// process $user_info;
}
Function (method) without any parameters is best. Function with one paremeter is better than function with 2 parameters. Function with 2 parameters is better than function with 3 parameters and so on.
#Florianh has given a perfect solution how your code can be improved. With this comment, I would like to elaborate on the "why" part from a system design perspective.
From an Object Oriented perspective, other objects should be able to manipulate attributes. That is why attributes should never be defined as "public". They should be "private" e.g.:
private var $name;
The reason for this is when other objects would manipulate this variable, the correct working of the object is at risk. Methods, on the other hand, can be defined publicly:
public function register()
Accordingly, the manipulation of the attributes will happen through the appropriate methods. A method can be used to also evaluate the correctness of operations on the attributes.
There are two operations that can happen: reading the current value of an attribute by using Get methods and saving a new value of an attribute by using Set methods.
A good practice would be to implement a get method for each class attribute. Each attribute that can be modified, should have an appropriate set method as well.
Sometimes it is better to not implement a get/set method (e.g.: showData()) after all. This is because the usage of getters and setters within a particular class may possibly lead to a reduced performance. However, this means that when changing or implementing the class, one must be careful when trying to save false information and as a result putting the integrity of the class at risk.
Now, consider the fact that you decide to use only one phone number instead of both a phone- and mobile number. When the mobile number becomes deprecated, your main program still remains the same. All you have to do is change/remove one method. The advantage of using getters and setters is an increase in adaptability and maintainability.
I make array of keys like
$fields = array('field1', 'field2');
function register (array $values, array $keys)
{
$data = array();
foreach ($keys as $one)
{
if (isset($values[$one])) $data[$one] = $values[$one];
}
// or you can use array functions like array_flip and after - array intersect
}
I'd make it this way
fields=explode(",","name,surname,lastname,street,city,region,zip,country");
user_registration($fields);
Because I am sure these variables coming from $_POST

What is the best way to store configuration variables in PHP?

I need to store a bunch of configuration information in PHP.
I have considered the following....
// Doesn't seem right.
$mysqlPass = 'password';
// Seems slightly better.
$config = array(
'mysql_pass' => 'password'
);
// Seems dangerous having this data accessible by anything. but it can't be
// changed via this method.
define('MYSQL_PASSWORD', 'password');
// Don't know if this is such a good idea.
class Config
{
const static MYSQL_PASSWORD = 'password';
}
This is all I have thought of so far. I intend to import this configuration information into my application with require /config.inc.php.
What works for you with regard to storing configuration data, and what are best practices concerning this?
I've always gone with option #2 and just ensure that no one but the owner has ANY sort of access to it. It's the most popular method among PHP applications like Joomla, vBulletin, Gallery, and numerous others.
First method is too messy to me (readability) and the third is WAY too dangerous to do. I've never thought about the Class method, so someone else can provide their input on that one. But I guess it's fine so long as the right access is used on the class' usage.
Example..
define('EXAMPLE1', "test1"); // scenario 1
$example2 = "test2"; // scenario 2
function DealWithUserInput($input)
{
return eval($input);
}
Now this example of code is really dumb, but just an example. Consider what could be returned by the function depending on which scenario the user could try to use in their input.
Scenario 2 would only cause an issue if you made it a global within the function. Otherwise it's out of scope and unreachable.
I'd say it also depends of userbase a bit. If configurations has to be very user friendly or user has to have ability to change config via web etc.
I use Zend Config Ini for this and other settings are stored in SQL DB.
I generally use the second method... When handling database connections I generally open a connection at the beginning of the request, then close it at the end. I have a function that establishes the connection, then removes the username/password from the global array (with the unset() function), This prevents other parts of the system from accessing the "sensitive" mysql connection data.
I'm also with option 2 for most config values. If you were going to implement the Class then I would tie the specific values to the Class that it affects instead of a general config Class.
In your example, your Class would be for database connections and an instance would save the password, db_name, etc. This would encapsulate the data properly and also provide an easy means to create multiple connections if that was ever needed.

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