CodeIgniter CRUD view abstraction - php

I'm building a CMS using CodeIgniter and I'm stumped on the best way to go about handling the various CRUD views. Given that my URL is similar to...
mydomain.com/admin/app/content/pages/edit
...where 'admin' is my controller and 'app' is my action method, I currently map segments 3, 4, and 5 to actual directories/files, like so:
/views
/admin
/content
/pages
list_view.php
edit_view.php
add_view.php
/banners
list_view.php
edit_view.php
add_view.php
One caveat is that I need to call different non-CRUD model methods depending on which page is being called, so my app() action method is starting to have have a nasty if..else block. Also, each section's views are going to look different, because of different table data, so I don't see how I can avoid having a bunch of view pages. Obviously the downside of all this is that 1) I'm repeating a lot of code, and 2) if I add a new admin section I have to physically make a slew of new directories and add a new portion to the if...else block.
So my questions are:
How can I reduce the number of directories and view pages I'm creating?
Can list_fields() or field_data() methods lend itself to any automation?
One idea I had was to profile the table I'm interacting with, create a dynamic associative array that defines which fields I want to expose as well as the type of form element it should be, and then pass that off to a common view. Thoughts? Flaws?

While this may not directly answer to your question, it may provide you with a basis on which to design your CRUD. I've used GroceryCRUD for quite a while now and pretty much swear by it for basic and advanced CRUD operations. It's pretty well designed and built and apart from the bespoke file structure, would appear to offer all that you're looking for.
The CRUD could easily be modified to incorporate the file/url structure you're looking for too.
See http://www.grocerycrud.com/

You can extend the CI_Model and use some reflection functions like getProperties() to help with your generic CRUDs. In conjunction with CI's list_fields() like you mentioned, you could definitely create some generic pages to do so.
An example that can process form data for any object might be
function processForm() {
$props = $this->self->getProperties(ReflectionProperty::IS_PUBLIC);
foreach ($props as $prop) :
$prop->setValue($this,$this->input->post($prop->getName()));
endforeach;
}
where
$this->self = new ReflectionClass($this);

Related

Why separate Model and Controller in MVC?

I'm trying to understand the MVC pattern in Phalcon.
In my current application I only need ONE template file for each table. The template contains the datagrid, the SQL statement for the SELECT, the form, add/edit/delete-buttons, a search box and all things necessary to interact with the database, like connection information (of course using includes as much as possible to prevent duplicate code). (I wrote my own complex framework, which converts xml-templates into a complete HTML-page, including all generated Javascript-code and CSS, without any PHP needed for the business logic. Instead of having specific PHP classes for each table in the database, I only use standard operation-scripts and database-classes that can do everything). I'm trying to comply more with web standards though, so I'm investigating alternatives.
I tried the INVO example of Phalcon and noticed that the Companies-page needs a Companies model, a CompaniesController, a CompaniesForm and 4 different views. To me, compared to my single file template now, having so many different files is too confusing.
I agree that separating the presentation from the business logic makes sense, but I can't really understand why the model and controller need to be in separate classes. This only seems to make things more complicated. And it seems many people already are having trouble deciding what should be in the model and what should be in the controller anyway. For example validation sometimes is put in the model if it requires business logic, but otherwise in the controller, which seems quite complex.
I work in a small team only, so 'separation of concerns' (apart from the presentation and business logic) is not really the most important thing for us.
If I decide not to use separate model and controller classes,
what problems could I expect?
Phalcon's Phalcon\Mvc\Model class, which your models are supposed to extend, is designed to provide an object-oriented way of interacting with the database. For example, if your table is Shopping_Cart then you'd name your class ShoppingCart. If your table has a column "id" then you'd define a property in your class public $id;.
Phalcon also gives you methods like initialize() and beforeValidationOnCreate(). I will admit these methods can be very confusing regarding how they work and when they're ran and why you'd ever want to call it in the first place.
The initialize() is quite self-explanatory and is called whenever your class is initiated. Here you can do things like setSource if your table is named differently than your class or call methods like belongsTo and hasMany to define its relationship with other tables.
Relationship are useful since it makes it easy to do something like search for a product in a user's cart, then using the id, you'd get a reference to the Accounts table and finally grab the username of the seller of the item in the buyer's cart.
I mean, sure, you could do separate queries for this kind of stuff, but if you define the table relationships in the very beginning, why not?
In terms of what's the point of defining a dedicated model for each table in the database, you can define your own custom methods for managing the model. For example you might want to define a public function updateItemsInCart($productId,$quantity) method in your ShoppingCart class. Then the idea is whenever you need to interact with the ShoppingCart, you simply call this method and let the Model worry about the business logic. This is instead of writing some complex update query which would also work.
Yes, you can put this kind of stuff in your controller. But there's also a DRY (Don't Repeat Yourself) principle. The purpose of MVC is separation of concerns. So why follow MVC in the first place if you don't want a dedicated Models section? Well, perhaps you don't need one. Not every application requires a model. For example this code doesn't use any: https://github.com/phalcon/blog
Personally, after using Phalcon's Model structure for a while, I've started disliking their 1-tier approach to Models. I prefer multi-tier models more in the direction of entities, services, and repositories. You can find such code over here:
https://github.com/phalcon/mvc/tree/master/multiple-service-layer-model/apps/models
But such can become overkill very quickly and hard to manage due to using too much abstraction. A solution somewhere between the two is usually feasible.
But honestly, there's nothing wrong with using Phalcon's built-in database adapter for your queries. If you come across a query very difficult to write, nobody said that every one of your models needs to extend Phalcon\Mvc\Model. It's still perfectly sound logic to write something like:
$pdo = \Phalcon\DI::getDefault()->getDb()->prepare($sql);
foreach($params as $key => &$val)
{
$pdo->bindParam($key,$val);
}
$pdo->setFetchMode(PDO::FETCH_OBJ);
$pdo->execute();
$results=$pdo->fetchAll();
The models are very flexible, there's no "best" way to arrange them. The "whatever works" approach is fine. As well as the "I want my models to have a method for each operation I could possibly ever want".
I will admit that the invo and vokuro half-functional examples (built for demo purposes only) aren't so great for picking up good model designing habits. I'd advise finding a piece of software which is actually used in a serious manner, like the code for the forums: https://github.com/phalcon/forum/tree/master/app/models
Phalcon is still rather new of a framework to find good role models out there.
As you mention, regarding having all the models in one file, this is perfectly fine. Do note, as mentioned before, using setSource within initialize, you can name your classes differently than the table they're working on. You can also take advantage of namespaces and have the classes match the table names. You can take this a step further and create a single class for creating all your tables dynamically using setSource. That's assuming you want to use Phalcon's database adapter. There's nothing wrong with writing your own code on top of PDO or using another framework's database adapter out there.
As you say, separation of concerns isn't so important to you on a small team, so you can get away without a models directory. If it's any help, you could use something like what I wrote for your database adapter: http://pastie.org/10631358
then you'd toss that in your app/library directory. Load the component in your config like so:
$di->set('easySQL', function(){
return new EasySQL();
});
Then in your Basemodel you'd put:
public function easyQuery($sql,$params=array())
{
return $this->di->getEasySQL()->prepare($sql,$params)->execute()->fetchAll();
}
Finally, from a model, you can do something as simple as:
$this->easyQuery($sqlString,array(':id'=>$id));
Or define the function globally so your controllers can also use it, etc.
There's other ways to do it. Hopefully my "EasySQL" component brings you closer to your goal. Depending on your needs, maybe my "EasySQL" component is just the long way of writing:
$query = new \Phalcon\Mvc\Model\Query($sql, $di);
$matches=$query->execute($params);
If not, perhaps you're looking for something more in the direction of
$matches=MyModel::query()->where(...)->orderBy(...)->limit(...)->execute();
Which is perfectly fine.
Model, View and Controller were designed to separate each process.
Not just Phalcon uses this kind of approach, almost PHP Frameworks today uses that approach.
The Model should be the place where you're saving or updating things, it should not rely on other components but the database table itself (ONLY!), and you're just passing some boolean(if CRUD is done) or a database record query.
You could do that using your Controller, however if you'll be creating multiple controllers and you're doing the same process, it is much better to use 1 function from your model to call and to pass-in your data.
Also, Controllers supposed to be the script in the middle, it should be the one to dispatch every request, when saving records, when you need to use Model, if you need things to queue, you need to call some events, and lastly to respond using json response or showing your template adapter (volt).
We've shorten the word M-V-C, but in reality, we're processing these:
HTTP Request -> Services Loaded (including error handlers) -> The Router -> (Route Parser) -> (Dispatch to specified Controller) -> The Controller -> (Respond using JSON or Template Adapter | Call a Model | Call ACL | Call Event | Queue | API Request | etc....) -> end.

How should I divide my code using CodeIgniter?

I have searched the web and found only styling code posts. I want to write site using Code Igniter and I wonder how should I maintain my code.
For example:
Should I use one class for static pages and methods for each page or separate file for every static page. Should I use the same file to load dynamic pages or different one?
Can I use some common code and include it automatically to every class?
How can I have lets say header_view footer_view etc and then just load->view('whatever') and footer, header and other files would load automatically. Maybe there is better way to do that?
In generall what are the best practices when coding using CodeIgniter.
You can use one single class for static pages (and use one method for each page).
You can use the same one to load dynamic pages, but it is better IMO to load them with a separate class. It will be easier to maintain later.
Using common code: You can always override the CI_Controller with your own, and instantiating controllers from yours. Here is an example about how to do it.
You can load multiple views in a single controller function. A view doesn't have to be a full html document. You can also load the same view multiple times (for example in a loop).
Best practices: CodeIgniter is an MVC framework. IMO, MVC is a best practice. Always use the framework's documented features if they are suitable for what you want to achieve (CodeIgniter's documentation is very good. That link is momentarily offline, so please try this one).
Codeigniter is a MVC based framework, MVC is basically used for organizing your code, so at last its up to you how you are going to use it so ease you on the long term.
Basically when I design large projects in codeigniter I tried to to make unit of functionality at one place lets take example of any simple users, messages based project.
I tried to make functionality by grouping main topics, in this example user will be a controller, in that controller there will be methods like login, register, edit, listing, forgot_password now I'll create single model with all the methods which will give data for these above methods. by using this methods our urls will be also meaningfull like /user/login, /user/register etc
like that if its messages I will create controller message and add all related methods in it so that my related functionality will be in a single group.
as far as the question of static pages you can also group them in a single controller if they can be a part of group.
you can also use codeigniter's caching technique for static pages so that your pages will load faster

Creating a subview in PHP MVC

I recently went through some tutorials on how to program your own PHP MVC framework. To avoid some questions and comments: I don't want to use it in a productive environment, I just like to fiddle and get the idea of whats going on in MVC.
So far I am able to have single pages eg. http://domain/news/show/3 shows me the news-record from the database with id 3 and http://domain/news/all lists them all on one page.
Now I have multiple entities and thus multiple lists and want them all to appear on one page. Preferably the page you see when you open http://domain/
Do I have to write a new model and controller that makes calls to the other models? I'm kinda unsure how to achieve this.
There is no strict definition or convention on this that I'm aware of.
What I would do is this:
Class Overview
Controller_Homepage
Controller_News
Model_NewsArticle
Behavior
Controller_Homepage
Action_Index fetches multiple Model_NewsArticle entities, has them rendered, and passes the output to view. Also fetches any other entities you may need and gives their rendered output to view.
Controller_News
Action_List fetches multiple Model_NewsArticle entities, has them rendered, and passes the output to view.
Action_View calls Model_NewsArticle::factory($id), has it rendered, and passes the output to view.
Model_NewsArticle
Contains a static factory method that accepts an $id. Returns an instance of Model_NewsArticle.
Contains methods used to find multiple articles. A query builder would be nice here.
That's by no means comprehensive and I've left out lots of little details, but it's fairly simple and is pretty dry.
This is a matter of preference really. Having another controller and model makes code separation easier in larger projects. Personally, I would only make a new controller since it is a different page with potentially different actions, and I would use the existing models to get the data to keep your code DRY (Don't Repeat Yourself).

Beginner CodeIgniter concepts - Reusable view code, where to go? (Helper?)

I am a beginner with CodeIgniter still struggling to get a complete grasp on how to use the MVC ideology most cleanly.
I am writing a basic CMS system with the ability to vote on entries and follow people etc, consequently, I have found myself using the same or similar pieces of code across multiple views here and there consisting of various pieces of html and logic such as:
Voting panel
Follow/Unfollow panel
Login/Logout panel
Code to check if a user is logged in etc...
I am wondering where to put this code so it can be unified? I am thinking a helper is the way to go? If I declare the helper in the controller, it can be called from the corresponding view right?
Some of the elements are dynamic - such as a follow/unfollow button - It would need to check if you are already following the user or not and display the appropriate button, which would require a model to check. What I have now is that all the logic is in the controller and it returns an appropriate button, but it seems weird to be returning formed html code in a controller return as well. Should it be more like:
controller checks if you are following someone
the controller passes a boolean to the view
the view calls the helper with this value to draw the appropriate button
Also, as a secondary question, I have been doing a fair bit of looping through mysql arrays in foreach loops to process mysql results returned from the view. It seems like my views are getting somewhat complicated, but I can't think of another way to do it, although perhaps this should be done in another helper as well?
Apologies if this is a naive or repetitive question, there is indeed a lot of discussion surrounding this subject but it is not always easily relatable to another project.
Helpers are certainly one way to modularize anything that isn't DRY. Another is to use Partial Views. CodeIgniter looks like it supports partial views. Here's a good breakdown - not PHP specific but the discussion should be agnostic.
As far as handling user logins is concerned, you will probably want to use a static class and the singleton design pattern, which will allow you to check to see if a particular user is logged in or not anywhere in your application. There is a good tutorial here
http://www.phpandstuff.com/articles/codeigniter-doctrine-scratch-day-4-user-login
Loading the helper, I don't believe loading it in your controller will automatically load it in your view. I think you have to re load the helper in your view file, or you have to autoload the helper. (cant remember off top of head but Im pretty sure).
Regarding looping through the mysql results, you should be using a model for this, always. Any functions which are grabbing or sorting information from your applicaiton, should be done within the model. Then, in your view file you loop through the results and format the data how you choose to.
When developing http://newspapair.com which has the vote functionality you mentioned I used helpers and custom classes to spread the functionality across multiple views.
Helper - has functions without a class. So a standalone function or group of functions can be placed in a file and saved as a helper.
For instance I used a helper with generic form processing functions for NewsPapair, instead of a static class. But this is not the "best practices" thing to do. I did it this way because I already had the functions from a previous project.
As far a looping through MySQL results, try to write a query that allows the DB Server to do the heavy lifting. This will make your code more efficient. Perhaps ask a question about a specific query with example code. Plus do all of the data gathering in your Model.

PHP: code design dilemma

This is a question with no real problem behind, just a product of my sick mind and drive to make things slightly weird :)
So, I have this PHP application build on top of my own MVC oriented framework (yes, I did my own instead of using existing one). And it is done by the book so we have model (data and database manipulation), view (templates filled with data and rendering output) and controller (handles requests, gets appropriate data from model, puts data into view). Classic and boring scenario with request routing done with .htaccess rules.
Yesterday I did some changes in my code, bug fixes, couple improvements, etc. And I felt strong urge to rearrange the code of controllers. They feel somewhat heavy and bloated and number of methods makes it hard to navigate through the file, and such stuff. I'm sure everybody knows what I'm talking about.
I'm thinking about breaking my controller class into many classes, each one handling only one type of request like login or register or showProfile or killMe.
Now controller class has public methods corresponding to parts of user friendly (or maybe SEO friendly) urls and routing class invokes proper controller and it's method according to url content.
Change I'm thinking about would shift a little routing mechanism into invoking specific controller and it's Execute() method.
For example, for url = "www.example.com/users/login"
now it looks like that:
$controller = new url[0]();
$method = url[1];
echo $controller->$method();
and now url would change to "www.example.com/login" and routing code would look like that:
$controller = new url[0]();
controller->Execute();
I omitted parts where I parse urls and extract routing info from them as it is irrelevant to my question.
What benefits I see in that change?
one dedicated class per one request
smaller files
smaller code
easier maintenance
limited danger of breaking working controller when adding new features(new types of request) or fixing bugs
Disadvantages?
possibly a lot of classes
possible performance hit
???
And my question is about what do you think about that idea and does it make any sense at all. And of course I'm more interested why I shouldn't do it than why I should. So if you can think of any reasons why that would be terrible idea and abomination please speak now before it will be too late :)
EDITED
Clarification of a question:
I'm asking whether I should break my single big controller which handles many types of requests by it's methods into many small controllers each of them handling only single type of request.
Now I have controller Users which handles requests like "login", "showLoginForm", "register", "activate", etc. Refactored code would consist of separate controllers for each of these requests.
A disadvantage I can think of for both the old and new methods is that you are mapping urls directly to class names. If you'd like to change the url you'd have to change the class name. If you'd like to have different urls for different languages, you'll have to add a layer that will map urls to class names anyways.
This is why I'd rather have a routing class that will map urls to class names which provides you a seam to change things.

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