Programming

Selecting Your Next App Dependency

We often turn to open source or proprietary packages for adding functionality to our apps. Here are some key points and questions to ask when selecting your next dependency. This list can help compare multiple packages to determine which fits our needs better. The goal is to find well thought out packages because our apps depend on them.

Documentation

Documentation is often the first place we look when there are questions. If the package is well documented then developing a solution will be easier.

  • Does documentation exist?
  • Is the documentation up-to-date?

Community

An active community signals to us this package is adopted and being used by other people. Finding whether the community is active should be easy. My go to places are:

  • Stackoverflow (Are people asking questions about this package? Are the questions answered?)
  • GitHub (When was the last time the package was updated? How many issues exist? Do the maintainer(s) respond to issues? How many pull requests? Do the maintainer(s) respond to pull requests? Does the package follow semantic versioning? How many stars?)
  • Package specific forum (Does it exist? Is the forum active?)
  • Google

If the community is actively helping other people it’s a good sign. The chances of getting help with an active community are higher than if there was little to no community.

Extendability

Often times the package won’t meet our requirements 100% so we must add additional functionality.

  • How easy is it to build a module?
  • Are there hooks or events to add additional functionality without modifying core code?

Code Coverage

Well tested code can lead to less defects. Depending on a package that isn’t tested is risky.

  • Does the code base have tests?
  • How much of the code base is covered by the tests?
  • Are the critical parts of the package tested?

How To Bind An Interface To An Implementation In Laravel

Binding an interface to an implementation promotes good coding practices. As a result the code is less coupled, more maintainable, and testable.

Why might someone want to bind an interface using Laravel? To put an abstraction between the application and the concretion. A concretion is a class that implements the interface. It is a specific implementation, in our example it will be Amazon S3 file storage provider. The application doesn’t care which implementation it receives just that it receives an implementation with the guaranteed functions.

Lets build functionality to interact with files on a storage provider such as Amazon S3. Initially all files will be uploaded and deleted on S3 only. There are other ways to accomplish this and the main goal is to demonstrate how to bind an interface to an implementation and not so much the actual code to upload to a storage provider.

Create An Interface

The interface will determine which functions are available on the concrete implementation through the binding.

Create The Concrete Implementation

The concretion is an Amazon S3 file storage provider. This file is where Amazon specific upload/delete functionality goes.

Create The Laravel Service Provider

The Laravel service provider is the mechanism that binds the FileStorageInterface to the S3FileStorage class implementation. This means if we use dependency injection for the FileStorageInterface or use App:make it will automatically resolve to the S3FileStorage class.

Using The Interface

In the below example we are not using the implementation directly. Instead it is automatically resolved through the service provider which returns the concrete implementation. Laravel will automatically resolve dependencies if they are in the __construct() functions. We can see below that the controller doesn’t know about Amazon and nor should it. I am only using the controller in this example to provide a demonstration. There are other places where we would use the storage provider that might better organize the code.

Final Thoughts

If we wanted to swap out for Dropbox or some other provider the impact is minimal, create a Dropbox implementation and change the provider. The application would now use the Dropbox implementation instead of the Amazon S3 implementation.

Following this pattern can also help separate the application from Laravel which could make reusing this code in other projects easier than if the Amazon S3 code were included in a model directly. Definitely think about how to best structure your code and not to fall into the framework convenience trap of putting everything in a model, controller or view. In most cases there are better places for code than those 3 areas.

Framework Convenience Trap

The idea is “x” framework provides a level of convenience that can make developers sloppy.

This often happens because frameworks tend to make developing easier. So easy we forget to take a step back and figure out how all the pieces come together.

If the framework is modeled on the model view controller (MVC) pattern. The convenience trap for developers is adding unnecessary amounts of logic into controllers or models. It’s easy to do and get the work “done” and out of the way if no testing is involved. Generally the problem with putting unnecessary amounts of logic in controllers or models is hard to test which subsequently causes the application to be brittle.

For example:
Oh looky here something database related this needs to go in a model or hey this interacts with the user’s input this probably goes in the controller.

The framework should not be the application, but a portion that compliments the development.

Note: The above generally applies to larger apps and not small apps that may have a short lifecycle.

How to mitigate the framework convenience trap?

  1. Write tests for the application. If tests are written chances are the structure of the app is designed better.
  2. Learn software best practices.
  3. Don’t code in a silo. Talk to other developers.
  4. Realize no one has perfect code and let someone critique your code. DON’T TAKE IT PERSONAL.

Awesome list of free beginner, intermediate, and advanced programming courses

Programming is useful and important.

I like to compare programming to oil in that cars require oil to operate and business require programmers. If a business intends to compete most likely they have an IT team. Many times the competitive advantage for a company relies on technology. Most technology if not all requires software development.

Even if very basic programming interests you there are some awesome courses. Some courses are self-paced and some have deadlines.

Awesome list of courses

Laravel 4 Project On Shared Hosting

Laravel 4 is capable of running on a shared hosting environment. It’s a lot easier than you probably think.

  1. Login to your host and go to your home directory. This does not mean your public home directory, they are separate.
  2. Upload all the contents Laravel project EXCEPT the public folder to your home directory.
  3. Upload the contents of your Laravel public directory to your public directory on your host. The public directory is sometimes called public_html.
  4. Edit file paths.php located in the bootstrap folder so the public path matches the path to your public directory on your host.

After completing each of those steps you should now have a working Laravel 4 project on a shared hosting environment. This assumes the shared host has all the PHPmodules required to run Laravel as well. I was able to accomplish this on HostGator.

If you have any questions feel free to ask.

Xampp Send Email Issues

After upgrading my xampp installation I had issues sending email.

I wrote a small test PHP page and it was saying my emails were being sent, but I never received them. Obviously something was misconfigured.

I thought I correctly edited my php.ini file, but it turns out all the tinkering I did with it may have caused the issues.

Search your php.ini file for [mail function].

  1. Remove the comment on smtp and smtp_port by removing the semi colons before them.
  2. Add smtp server, port number. I’m using my ISP smtp server. Find your ISP smtp settings by searching google.
  3. sendmail_from needs to be set only if you don’t specify a from header in your PHP code. This can be set to any email address.
; XAMPP: Comment out this if you want to work with an SMTP Server like Mercury
SMTP = examplesmtpserver.com
smtp_port = 25

; For Win32 only.
; http://php.net/sendmail-from
sendmail_from = email you want to send from (ex: [email protected]). This needs to be set or a from header must be added in the php mail code

 

Here is test PHP code that I used. You’ll have to edit the “to” variable to your email address.

$to = "your email here";
$subject = "Test Email";
$body = "Email for testing Xampp";

if (mail($to, $subject, $body)){
	echo("Message successfully sent!");
} 
else{
	echo("Message delivery failed…");
}

After visiting your created PHP page the page should tell you whether PHP sent your email. Please note that just because PHP says it sent the mail doesn’t actually mean the email will be delivered  While I was having issues PHP still said it successfully sent, but I wasn’t receiving emails. If you’re still having problems after it says email successfully sent you’ll have to do more digging.

Contact me if you have questions I’ll do my best to assist [email protected].