An Army of PHP Service Classes

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    An Army of PHP Service Classes with Leanna Pelham
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    Yay, we got rid of a flat function. Well, not so fast.
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    Inside battle, we're calling a flat function didJediDestroyShipUsingTheForce?
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    That's no bueno. This lives at the bottom of functions.php.
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    In our app, this is only called from inside battle, and since it obviously relates to battles,
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    let's move it into BattleManager.
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    Make it a private function. Why did I make it private? Well, do we need to use this function
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    from outside of this class? No, the only code using it is up in battle.
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    So this is a perfect candidate to be private.
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    Above in battle, update the calls to be $this->didJediDestroyShipUsingTheForce?
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    The force of our app is happy again. Now if someday we did want to use this function
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    from outside of BattleManager, then we could change it to public.
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    Okay, so why not just make everything public?
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    Isn't that more flexible? Yes, but making this private is nice. It means that if I want to change this function,
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    add arguments, or even change what it returns, I know that the only code that will be affected
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    will be right inside this class. If it's public, who knows what code I might break in my app.
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    Start with private. Make it public only if you need to.
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    The same rule goes for protected, something we'll talk about later with inheritance.
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    Let's make sure we didn't bust things. Refresh.
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    Yes. In functions.php, only the get_ships function remains. You guys know what to do.
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    Move it into a class. Should we move it into BattleManager? No.
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    It doesn't relate to battles. Instead, create a new class for this.
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    How about ShipLoader?
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    Let's work our magic. Go grab get_ships and move it into ShipLoader.
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    Remove the old commented code and make the function public.
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    Also rename it from get_ships to getShips. That's a more common naming standard for methods in a class.
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    Yep, that's great. Now we need to update the code that calls this function.
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    But first, open functions.php and require the new ShipLoader.php.
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    GetShips is used in battle.php and index.php. Start there. To call the method, create a $shipLoader variable
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    and create a new ShipLoader object.
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    Now just shipLoader->getShips.
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    Do the same thing in battle.php.
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    I think it's time to try it. Click to create a new battle.
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    Looks pretty good. Set up a new battle and engage.
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    Okay, battle.php works too. And all the flat functions are gone.
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    Object orient all the things. So if you look in functions.php, well there aren't any functions here,
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    just require statements and even those we'll get rid of eventually.
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    To celebrate, give this a more appropriate name, bootstrap.php.
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    Update this in battle.php
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    and index.php. Refresh once more. Let's keep going.
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An Army of PHP Service Classes


In this tutorial we are going to continue to remove the flat functions in our code. We'll refactor one of them to a private function and create a new ShipLoader service class to clean up the rest. With this refactoring in place, we'll be able to rename the functions.php file since it won't contain any functions any longer.

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