Workflow Engine for Yii 2 Framework
, (*1)
INSTALLATION
The preferred way to install Workflowii is through composer., (*2)
You can either run:, (*3)
php composer.phar require fproject/workflowii "*"
or add this block to the require section of your composer.json file:, (*4)
"require" : {
"php" : ">=5.4.0",
"yiisoft/yii2" : "*",
"fproject/workflowii": "*",
// ...
}
REQUIREMENTS
The minimum requirement by Workflowii:
- Your Web server supports PHP 5.4 or above
- Your Web server is running on Yii 2.0.0 or above, (*5)
QUICK START
Configuration
In this simple start guide we use default configuration settings, but note that workflowii is designed to be highly
flexible so to adapt to a lot of execution contexts., (*6)
Create A WorkflowSource
A workflow source is defined as a PHP class that implements the \fproject\workflow\core\IWorkflowSource interface. This interface
declares the getDefinition() method that must return an array representing the workflow of a model object., (*7)
Let's define a very simple workflow source that will be used to manage article posts represented by Article model class.
This workflow source will simply return the same workflow for all model object instances of Article, by specifying a PHP
associative array as return value of getDefinition() method:, (*8)
ArticleWorkflowSource.php, (*9)
class ArticleWorkflowSource implements \fproject\workflow\core\IWorkflowSource
{
public function getDefinition($model) {
return [
'initialStatusId' => 'draft',
'status' => [
'draft' => [
'transition' => ['published','deleted']
],
'published' => [
'transition' => ['draft','deleted']
],
'deleted' => [
'transition' => ['draft']
]
]
];
}
}
Attach ActiveWorkflowBehavior To The Model
Now let's have a look to our Article model that extends from \yii\db\ActiveRecord and has a column named
status of type string., (*10)
The last step is to associate the workflow definition with articles models. All things we have to do is overriding
the function behaviors() method in the Article model class and specify the ActiveWorkflowBehavior behavior as
return value. That's all, the workflowii's default configuration settings will do the rest for you., (*11)
Article.php, (*12)
/**
* @property integer $id
* @property string $title
* @property string $body
* @property string $status column used to store the status of the article
*/
class Article extends \yii\db\ActiveRecord
{
public function behaviors()
{
return [
\fproject\workflow\core\ActiveWorkflowBehavior::className()
];
}
// ...
By default, the ActiveWorkflowBehavior will search to find a workflow source class that has the same namespace with the
model class and has the class name is the model class name with suffix WorkflowSource. In this case, it will be ArticleWorkflowSource., (*13)
Thus, we are now ready to play with ArticleWorkflowSource workflow that dedicated for Article model., (*14)
Let's Use It !
Now that we are all setup, we can use the ActiveWorkflowBehavior methods to set/get the status of our articles : the ActiveWorkflowBehavior will
take care that the article doesn't reach a status where it is not supposed to go, depending on the workflow definition that we have created., (*15)
$article = new Article();
$article->status = 'draft';
$article->save();
echo 'article status now is : '. $article->workflowStatus->label;
This will print the following message :, (*16)
article status is : Draft
If you do the same thing but instead of draft set the status to published and try to save it, the following exception is thrown :, (*17)
Not an initial status : ArticleWorkflow/published ("ArticleWorkflow/draft" expected)
That's because in your workflow definition the initial status is set to draft and not published., (*18)
Now we will go further. This time we are not going to perform the transition when the Article is saved (like we did in the previous
example), but immediately by invoking the sendToStatus method. Our Article is going to try to reach status published passing through deleted
which is strictly forbidden by the workflow. Will it be successful in this risky attempt of breaking workflow rules ?, (*19)
$article = new Article();
$article->sendToStatus('draft'); // OK
$article->sendToStatus('deleted'); // OK
$article->sendToStatus('published'); // Error!
There is no transition between deleted and published, and that's what Workflow tries to explain the problem:, (*20)
Workflow Exception – fproject\workflow\core\WorkflowException
No transition found between status ArticleWorkflow/deleted and ArticleWorkflow/published
Yes, that's severe, but there was many ways to avoid this exception like for instance by first validating that the transition was possible., (*21)
What's Next ?
This is just a very simple way of using the ActiveWorkflowBehavior. Workflowii has much more functionalities enough to assist you
in your workflow management inside your Yii 2 web app., (*22)
In the meantime you can have a look to the Workflowii User Guide (still under dev) and send any feedback., (*23)
ROADMAP
- At the first stage, we build a workflow engine based on Yii 2 Framework with basic functionalities.
- At the second stage, we are planning to develop a web component that allows users display/edit workflows by
interacting with a RIA GUI, using HTML5 or Flex.
LICENSE
Workflowii is released under the Apache 2.0 License. See the bundled LICENSE.md for details., (*24)
LINKS
Wallogit.com
