stxh / MongoYii

A Yii MongoDB ORM

You can find a more user friendly version of this documentation on the extensions Github page: http://sammaye.github.io/MongoYii

MongoYii

Another active record handler for the Yii framework that supports MongoDB.

Rationale

There is already a great extension called YiiMongoDBSuite out for Yii so why make another? YiiMongoDBSuite has certain flaws which I wish to address:

• Does not support $or natively
• Very large and complicated code base
• Does not support the later versions of the PHP driver (1.3.x series) that well
• Obscured the MongoDB query language, layering a query language over the top

After some spare time I decided that I would take the liberty to make a MongoDB extension for Yii. It is basically a "glue" between MongoDB and Yii and it is designed to be quite free form in that respect.

There are a few points of design I wished to enforce:

• expose the MongoDB query language in its raw form
• make the programming of this extension simple and easy to maintain for all parties
• make sure this extension worked with both the new and old versions of the MongoDB driver
• attempt to make things a little more performant
• try to follow Yiis own CActiveRecord API as much as possible without compromising MongoDB "semantics" such as the name for query operators and the use of a MongoCursor

Okay, so we have got some of the rationale in place it is time to actually talk about the extension.

Setting up the extension

In order to use the extension you first need to set it up. The first thing to do is to download the source code and place it somewhere accessible within your applications structure, I have chosen protected/extensions/MongoYii.

Once you have the source code in place you need to edit your main.php configuration file (console.php will need modifying too if you intend to use this extension in the console) with the following type of configuration:

'mongodb' => array(
	'class' => 'EMongoClient',
	'server' => 'mongodb://localhost:27017',
	'db' => 'super_test'
),

And add the MongoYii directories to your import section:

'application.extensions.MongoYii.*',
'application.extensions.MongoYii.validators.*',
'application.extensions.MongoYii.behaviors.*',
'application.extensions.MongoYii.util.*'

That is the basic setup of the extension.

You will notice that I use a EMongoClient. This is a bit deceptive since it actually represents MongoClient and MongoDB combined. This means that whenever you call the magic __call on the EMongoClient like so:

Yii::app()->mongodb->getSomething();

It will either try and call a function of getSomething in EMongoClient or, if the function does not exist, try and call it within the MongoDB class.

If you wish to call a function on the MongoClient or Mongo class you will need to retrieve the connection object like so:

Yii::app()->mongodb->getConnection()->getSomething();

EMongoClient is also designed to handle full write concern and read preferences in a compatible manner with all versions of the driver.

Note: The models will by default seek a mongodb component within your configuration so please make sure that unless you modify the extension, or use it without active record, to make your default (master) connection be a component called mongodb.

If you wish to setup the log to insert entries into MongoDB (like in CDbLogRoute) you can add the following to your 'log' component configuration:

	'log'=>array(
		'class'=>'CLogRouter',
		'routes'=>array(
			array(
				'class'=>'CFileLogRoute',
				'levels'=>'error, warning',
			),

			[ ... ]

			array(
				'class'=>'EMongoLogRoute',
				'connectionId'=>'my_connection_id', // optional, defaults to 'mongodb'
				'logCollectionName'=>'my_log_collection', // optional, defaults to 'YiiLog'
			),
			
		),
	),

Composer

MongoYii fully supports Composer and is listed on packagist.

As an additional side note posted by @ujovlado on a related issue; if you are only using Composer for Yii extensions then you can set a more blanketed solution of simply changing your vendor-dir to protected/extensions:

{
    "config": {
        "vendor-dir": "protected/extensions"
    }
}

However to have automatic handling of loading MongoYii using Composer you would require to downgrade to 1.0.3 where the Yii installer is not deprecated. Failing both of those options you can also make your own script to handle what the removed installer used to.

Currently MongoYii does not handle namespaces and this is unlikely to change in Yii1.

Write Concern (formally "safe" writes)

This extension uses the new w variable globally to handle the level of write concern you wish to impose on MongoDB.

By default the extension will assume acknowledged writes, this means safe=true or w=1 depending on the version of your driver. To change this simply add w to your mongodb component configuration and give it a value according to the PHP documentation.

For those using the 1.3.x series of the driver there is also a j option which can be set to either true or false within the configuration which allows you to control whether or not the write is journal acknowledged.

Note: Write Concern is abstracted from the driver itself to make this variable compatible across all versions of the driver so please use the configuration or the EMongoClient w and j class variables to set the write concern when you need to, otherwise that write concern will not be used within active record.

Note: Write Concern works differently when you touch the database directly and the write concern issued within the EMongoClient class will have no effect. Instead you should always ensure in this case you specify the write concern manually according to your driver version.

This may change in the future but at the moment when you want the active record to go away it just will.

Read Preference

For those using the old driver there is only one extra configuration variable available to you, setSlaveOkay. Set this to either true or false in your configuration to make it possible to read from members of a replica set.

For those using the 1.3.x series of the driver you have the RP configuration variable. The RP configuration variable is a 1-1 relation to the options of setReadPreference on the MongoClient class with one exception. The first parameter is not a constant but instead the name of the constant. An example of using read preferences in your configuration would be:

'RP' => array('RP_SECONDARY' /* The name of the constant from the documentation */,
	array(/* Would normally be read tags, if any */))

Please refer to the drivers documentation for a full set of options here.

To change the Read Preference at any time please use the function applicable to your driver; for 1.3.x series:

Yii::app()->mongodb->setReadPreference(MongoClient::RP_PRIMARY, array());

and for pre-1.3:

Yii::app()->mongodb->setSlaveOkay(true);

Note: Unlike write concern, the RP and setSlaveOkay variables do not inter-lock between different versions of the driver, using the EMongoClient RP variable will not translate to slaveOkay.

Using MongoDB without Active Record

You can call the database directly at any time using the same implemented methods as you would using the driver normally. As an example, to query the database:

Yii::app()->mongodb->collection->find(array('name' => 'sammaye'));

So the active record element of MongoYii can quickly disappear if needed.

EMongoModel

The EMongoModel is a stripped down version of the EMongoDocument.

This was made separate from EMongoDocument to provide a small and slim active model for use on subdocuments. Whenever you make a class based subdocument you can extend this class.

The EMongoModel implements all that CModel does but with a few added and changed features.

Magic functions

The getters and setters should inherit all of Yiis own functionality.

Virtual Attributes

This extension supports virtual attributes via a doc block notation syntax of @virtual, for example:

class User extends EMongoModel{
    /** @virtual */
    public $somevar;
}

These variables can be used in the same way as everything else except they will never be saved in MongoDB.

Note: due to how PHP OO accession works it is a good idea to make all your record fields, virtual or not, public.

Relations

Unlike in SQL where you have many complicated types of relations, in MongoDB you tend to only have two:- one and many.

As you have guessed, you can only define two types of relation in this extension - one and many. Lets take a look at an example:

function relations(){
	return array(
		'others' => array('many', 'Other', 'otherId', 'sort' => array('_id'=>-1), 'skip' => 1, 'limit' => 10)
	);
}

You will recognise a lot of this from Yiis own active record, in fact a lot is the same. We define a name for the relation as a key and then we define either one or many in text (constants seemed useless with only two types) and then we define a class name, Other in this case, and then we define the foreign key in that class, otherId.

The default behaviour of relations is to attempt to use the primary key, _id, of the current model to query the foreign key. This is a problem for EMongoModel since it has no primary key. Make sure that if you use this in EMongoModel you define a on clause to replace the primary key of the current model.

The on clause supports multiple field types. It can take a DBRef or an ObjectId or an array of ObjectIds depending on how you define your document.

You can also, just like in Yii, define a where clause. This is a 1-1 relation to the syntax used within normal querying in MongoDB and the extension will basically merge this clause with the primary key field you define in order to query for the relation.

All relations are returned as EMongoCursors which is basically the Yii active record implementation of MongoCursor. There is no eager loading, if you wish to use eager loading please look into using iterator_to_array() on the return value from calling the relation.

Caching

Currently there is no relationship caching on relation types of many due to the historical reason of returning an EMongoCursor for all relationships. You can add caching by setting cache to true in the relation properties like so:

function relations(){
	return array(
		'others' => array('many', 'Other', 'otherId', 'cache' => true)
	);
}

Deprecation Notice

By default currently a many relation has no caching to it. This goes against how Yii works as such caching will be turned on by default at some point in the future: Sammaye#169.

The change will not happen for a long time to give people who have come to expect the behaviour of no caching a chance to move their code.

The ability to declare a relationship as uncached is staying. This will help for very large relationships that exist which should not really be brought into memory for performance reasons.

getDocument()

Just gets the docuemnt "as-it-is". This means that if you put meta objects in like nested EMongoModels it will get these back in the output.

getRawDocument()

Will strip away all classes used by the extension and return a document suitable for use with MongoDB.

getJSONDocument()

Will run getRawDocument() and then return its output as a JSON string.

getBSONDocument()

Will run getRawDocument() and then return its output as a BSON string.

EMongoDocument

The EMongoDocument extends EMongoModel and implements all of its features along with the needed features for database accession. It also implements as much as possible of CActiveRecord.

Note: The functions that allow database usage are not defined within this section of the documentation. Instead those functions are actually defined within the "Querying" section. Please move to the "Querying" section if you wish to read about this part of the EMongoDocument.

collectionName()

Returns a string representing the collection name. All active record models should implement this function although it is not abstract.

primaryKey()

Currently only returns _id as the key.

Using a Custom Primary Key

If you are using a primary key that IS NOT a ObjectId (otherwise known as a MongoId in the PHP driver) then you should override the getPrimaryKey function of the EMongoDocument to not return a MongoId:

public function getPrimaryKey($value=null){
	if($value===null)
		$value=$this->{$this->primaryKey()};
	return (string)$value;
}

You can, of course, add whatever procedure or formatting code you need within this function to make sure that your primary key is ready for MongoDB when it comes to querying.

Scopes

Scopes are fully supported in all the normal ways as with CActiveRecord but with one difference; the terminology.

The scopes, and queries, in this extension use these words to describe their parts:

• condition to describe the condition itself
• sort to describe the sort
• skip to describe offset
• limit to describe limit

As an example of a full default scope which omits deleted models to get the latest 10 skipping the first one:

array(
	'condition' => array('deleted' => array('$ne' => 1)),
	'sort' => array('date' => -1),
	'skip' => 1,
	'limit' => 11
)

You can also define your own scopes, however, it is a little different to how you are used to doing it in Yii:

function someScope(){
	$this->mergeDbCriteria(array(
		'condition'=>array('scoped' => true),
		'sort'=>array('date'=>-1),
		'skip'=>1,
		'limit'=>11
	));
}

As you will notice the _criteria variable within the EMongoDocument which would normally be a EMongoCriteria object is actually completely array based.

This applies to all scope actions; they are all array based.

To help you in not having the EMongoCriteria object the EMongoDocument provides a helper function for merging criteria objects called mergeCriteria. Using this function will have no impact on the model itself and merely merges criteria to be returned. As an example of using the mergeCriteria function:

function someScope(){

	$criteria = array(
		'condition'=>array('scoped' => true),
		'sort'=>array('date'=>-1),
		'skip'=>1,
		'limit'=>11
	);

	if($this->deleted)
		$criteria = $this->mergeCriteria($criteria,array('condition'=>array('deleted'=>1)));

	$this->mergeDbCriteria($criteria);
	reutrn $this;
}

Note: Just like in Yii, normally scopes are not reset automatically, please use resetScope() to reset the scope.

equals()

Checks if the current model equals another sent in as a parameter.

exists()

Checks if a document exists in the database with the criteria supplied as the first parameter.

clean()

Cleans the document of all properties and relations.

refresh()

Runs clean() and then re-populates the model from the database.

getCollection()

Returns the raw MongoCollection.

It is normally best not to use this but instead to use the extension wrapped editions - updateAll and deleteAll. The only difference of said functions from doing it manually on getCollection() is that these functions understand the write concern of the extension.

setAttributes()

It is important, nay, imperative that you understand exactly how, by default MongoYii assigns integers. Since MongoDB has no strict handling of field types it is very easy for boolean integers from the likes of checkboxes etc to end up as strings breaking your application and causing you to have to cast objects repeatedly or change the way you query (since, of course, MongoDB is type aware when querying).

MongoYii will convert any number, real integer (otherwise known as "positive" or "unsigned" integer), not starting with 0 and not possessing a letter to an int.

This is important because the largest integer MongoDB can natively store is only 32bit. In order to make MongoDB store larger integers you must use the native_long configuration variable available within the driver.

If you are on a 32bit system you will need to add another configuration variable to the stack: long_as_object.

Note: Integers greater than the systems limit will be left as strings. This means that on a 32bit system the maximum int you can assign from form data is 2147483647 while on a 64bit system it is 9223372036854775807. If you wish to use int data types from forms past your systems limits you will be required to process the fields yourself, either within the CHttpRequest handler or using a validator.

Example

So now that we have discussed the EMongoDocument lets look at the most base of example:

class User extends EMongoDocument{
	function collectionName(){
		return 'users';
	}

	public static function model($className=__CLASS__){
		return parent::model($className);
	}
}

This is the most basic document that can exist - no predefined schema and only a model function (same as Yii active record) and the tableName, otherwise known as the collectionName, are needed.

As time goes on you will want to add certain fields like virtual attributes and such to make your life easier:

class User extends EMongoDocument{

	/** @virtual */
	public $agree = 1;

	public $addresses = array();

	function collectionName(){
		return 'users';
	}

	public static function model($className=__CLASS__){
		return parent::model($className);
	}
}

Notice how I have added the addresses field despite not needing to? I do this due to the way that PHP uses magic functions.

If you access an array magically you cannot, in the same breath, manipulate it since it is an indirect accession of the variable. So a good tip here: if you plan on having subdocuments it might be good to explicitly declare the field as a variable within the class.

Querying

Querying attempts to expose the native MongoDB querying language as much as possible. A EMongoCriteria class is provided, however, it is not required and does not provide any more functionality than just doing it via arrays. The EMongoCriteria class is not relied on anywhere and is not needed.

find()

find() is really simple. It is essentially a 1-1 to the drivers own find() function and implements the same specifics. Just like the drivers edition, it also returns a cursor instance (EMongoCursor) which can be used to lazy load results from the database.

It will return a cursor irrespective of whether it finds results or not. However if it cannot find results then count will return 0 and the iterator will not have any iterations to it.

Note: The cursor does not eager load documents, instead if you wish to accomplish this please wrap the call to find in a call to iterator_to_array.

findOne() and findBy_id()

findOne, just like findBy_id is a straight 1-1 implementation of the drivers own findOne method and returns an active record record model if something was found, otherwise null.

The findBy_id function takes either a hexadecimal representation of a ObjectId in string form or wrapped in the MongoId class and will seek out a record with that _id using the findOne function, returning the exact same. It is basically a helper for findOne to make your life a little easier.

Scopes

The read functions of this extension have full support for scopes within models.

Example

Ok so now we have a basic grasp of querying lets look at an example:

$c = User::model()->recently()->find(array('deleted' => 0))->sort(array('joined' => -1))->skip(2)->limit(3);

This may look complicated but I will now break it down for you:

• User::model() gets our model
• ->recently() is actually a scope, this is not needed but good for demonstration purposes
• ->find(/*...*/) is basically the MongoDB drivers find method and returns a EMongoCursor which implements a MongoCursor
• ->sort() is basically the MongoDB drivers sort method on the MongoCursor
• ->limit() is, again, basically the MongoDB drivers own limit function on the MongoCursor

For a reference on what operators are supported please refer to the MongoDB documentation: http://docs.mongodb.org/manual/reference/operators/

Note: Other functions like findByAttributes have been omitted since it seems pointless with MongoDBs querying language to implement those.

save()

This saves the document and is used externally as a means to access either insert or update on the active record model, i.e.:

if($user->validate()) $user->save();

If the document is new it will insert otherwise it will update.

insert()

This is used internally by the active record model. If the record is new it will attempt to insert otherwise it will throw an error.

update()

This is used internally by the active record model. If the record is not new it will attempt to update it otherwise it will throw an error.

If you send in attributes into either this function or the save function it will attempt to do a $set on those attributes otherwise it will save the model.

delete()

This is used to delete the current active record.

deleteByPk() and updateByPk()

These are helpers to the update and delete functions except they act on the database directly, instead of through active record.

To show by example:

User::model()->deleteByPk($_id[, array('deleted' => 1)[, array('w' => 2)]]);
User::model()->updateByPk($_id, array('$set' => array('d' => 1)[, array('deleted' => 1)[, array('w' => 2)]]);

Arguments shown in [] are optional.

These functions can take both a string and a MongoId as the $_id parameter.

updateAll() and deleteAll()

Same as above really except these translate directly to the MongoDB drivers own update and delete functions.

Note: UpdateAll is multi true by default

Validation

The validation has pretty much not changed except for the names of certain validators due to Yiis own requiring SQL.

unique

The unique validator is now the EMongoUnqiueValidator.

array('username', 'EMongoUniqueValidator', 'className' => 'User', 'attributeName' => 'username')

exist

The exist validator is now the EMongoExistValidator.

array('user_id', 'EMongoExistValidator', 'className' => 'User', 'attributeName' => '_id')

EMongoIdValidator

This validator was added as a easy, yet flexible, method to automate the conversion of hexidecimal representation of MongoIds (for example: addffrg33334455add0001) to the MongoId object for database manipulation. This validator can also handle arrays of strings that need converting to MongoIds.

array('ids,id', 'EMongoIdValidator'), // ids is an array while id is a single string value

EMongoSubdocumentValidator

This is the subdocument validator, please see the "Subdocuments" section for full documentation.

Behaviours

EMongoTimestampBehaviour

This is the MongoYii edition of CTimestampBehavior behaviour and will use MongoDate fields, however, an expression can be added to timestampExpression to make the behaviour return integer timestamps.

The usage of the behaviour is very much alike to normal, infact only the name is different:

function behaviors(){
	return array(
		'EMongoTimestampBehaviour'
	);
}

Subdocuments

Subdocuments are, mostly, not automatically supported by this extension. There a couple of reasons, firstly due to performance - automating subdocument usage requires a lot of loaded classes to handle different subdocuments and their validation.

The other main reason is that, in any project I have done, whenever I tried to automate subdocuments through active record it has always resulted in me actually ditching it and doing the process manually. It has been proven many times that you rarely actually want automated subdocuments and normally you want greater control over their storage than this extension could provide.

So that is a brief understanding of the rationale behind the idea to ditch automatic subdocument handling within the active record.

This does not mean you cannot embed subdocument classes at all; when saving, the active record class will iterate the document and attempt to strip any EMongoModel or EMongoDocument classes that have sprung up.

This all aside, there is a subdocument validator and technically it can even accept multi-level nesting. Please bare in mind, though, that it will cause repetition for every level you use it on. This WILL have a performance implication on your application.

An example of using an array based subdocument is:

function rules(){
	return array(
		array('addresses', 'subdocument', 'type' => 'many', 'rules' => array(
			array('road,town,county,post_code', 'safe'),
			array('telephone', 'integer')
		)),
	);
}

While an example of a class based one is:

function rules(){
	return array(
		array('addresses', 'subdocument', 'type' => 'many', 'class' => 'Other'),
	);
}

type defines the type of subdocument, as with relations this is either one or many.

The validator will evaluate the rules as though they are completely separate from the originating model so in theory there is nothing stopping you from using any validator you want.

The error output for the validator will differ between the one and many types of subdocument. With one the validator will output the model errors directly onto the field however with many it will create a new element for each model (row) with embedded errors in that new element in the field on the parent, for example:

array(
	'addresses' => array(
		0 => array(
			'telephone' => array(
				0 => 'Some error here'
			)
		)
	)
)

Note: While on the subject, to avoid the iteration every time you save the root document (since validation is run by default in Yii on save) you should confine your subdocument validators to specific scenarios where they will be actively used.

Handling Subdocuments

As we already know MongoYii does not handle subdocuments automatically for you. if you wish to have an automatic handler for subdocuments it is normally considered good advice to make your own based on the scenarios you require. One reason for this is because many people have many different document setups and since there is no predefined schema for the subdocuments I cannot provide automated usage without short of taking every single possibility of subdocument existence into account.

For this explanation we will assume you do not wish to make your own subdocument handler, but instead, are fine using MongoYiis and PHPs own built in abilities. Handling subdocuments depends heavily upon how you intend to manage and use them.

Okay, let's start at the top; are you using a class for these subdocuments? If the answer is "Yes sir!" then chances are that your subdocuments are quite complex and has a section in your application all to itself with its own controller and everything like, for example, comments on a bog post.

Now the second question you must ask yourself; are you replacing these subdocuments every time you save them or do you want to use modifiers such as $push, $pull, $pullAll, $pushAll, $addToSet ectera?

If you wish to use modifiers each time then the best way to manage these type of documents is to make the subdocument singular class extend EMongoModel, for example, Comment would extend EMongoModel.

When, say, adding a comment to a post you would do:

if(isset($_POST['Comment'])){
	$comment=new Comment;
	$comment->attributes=$_POST['Comment'];
	if($comment->validate())
		$response = Post::model()->updateAll(array('_id' => $someId), array('$push' => $comment->getRawDocument()));
}

And you would use relatively similar behaviour for most other operations you need to perform. In this case MongoYii merely acts as a helper and glue for you to make life a little easier, however, at the end of the day it will not auto manage subdocuments for you.

If you are not using a class then chances are your subdocuments are quite primative and most likely are just detail to the root document and you are replacing them each time. This scenario also applies if you are using complex classes but you are replacing the subdocument list on each save.

If this is the case you can either use the subdocument validator mentioned above to process your subdocuments or you can actually programmably do this:

$valid=true;
$user=User::model()->findBy_id($uid);
if(isset($_POST['numbers'])){
	foreach($_POST['numbers'] as $row){
		$d=new Model();
		$d->attributes = $row;
		$valid=$d->validate()&&$valid;
		$user->numbers[] = $d;
	}
}
if($valid) $user->save();

as an example.

As an added side note you can actually treat the array fields within your document that contain the subdocuments the same as any other field. For example this will work:

$m=new Something();
$m->name='thing';
$parentClass->things[6] = $m;
$parentClass->save();

So subdocuments are very flexible in this extension and they do not corner you into thinking one way and one way only, much like MongoDB itself really.

Using the ActiveDataProvider

This extension comes with a CActiveDataProvider helper called EMongoDataProvider. It works exactly the same way except for how it is called.

Instead of using a EMongoCriteria or something similar you use arrays like so:

new EMongoDataProvider(array(
	'criteria' => array(
		'condition' => array(),
		'sort' => array(),
		'skip' => 1,
		'limit' => 1
	),
	/* All other options */
));

The criteria option basically relates to the parts of a cursor.

This extension does fully support CGridView (thanks to @acardinale for the fix) and it should also be able to take the CListView as well.

As a side note to the above, CGridView is best used when you predefine the schema you wish to display within the definition of the CGridView widget. So, to display an example for a user model:

$this->widget('zii.widgets.grid.CGridView', array(
	'id'=>'user-grid',
	'dataProvider'=>$model->search(),
	'filter'=>$model,
	'columns'=>array(
		'_id',
		'username',
		'addresses',
		'create_time',
		array(
			'class'=>'CButtonColumn',
			'template'=>'{update}{delete}',
		),
	),
));

This is normally the best method because, of course, MongoDB is schemaless (has a flexible schema is more appropriate) so sometimes it doesn't work so well in a rigid table.

EMongoCriteria

The EMongoCriteria class can help build modular queries across many segments of your application providing an abstracted layer with helper functions enabling you to better create complex queries.

A brief, yet complete, example of using the EMongoCriteria would be:

$c = new EMongoCriteria();
User::model()->find($c
				->addCondition(array('name' => 'sammaye')) // This is basically a select
				->addOrCondition(array(array('interest' => 'Drinking'), array('interest' => 'Clubbing'))) // This is adding a $or condition to our select
				->skip(2) // This skips a number of rows
				->limit(3) // This limits by a number of rows
					);

So you can see that quickly we can build very complex queries with ease.

Just like with CDbCriteria you can also set all of these properties of the query straight from the constructor like so:

$c = new EMongoCriteria(array(
	'condition' => array('name'=>'sammaye'),
	'limit' => 10
));

The EMongoCriteria class implements many of the functions you would expect of CDbCriteria.

setCondition() / getCondition()

These basically just sets and gets the condition of the query.

addCondition()

Adds a normal, non $or condition to the query and takes an array as its only parameter.

addOrCondition()

Adds an $or condition and takes an array of arrays as its only parameter with each nested array being a condition within the $or (just like in the driver).

It would be wise to note that calling this function will overwrite any $or previously placed in the condition.

getSort() / setSort()

Get and set the sort of the query.

getSkip() / setSkip()

Get and set the skip of the query.

getLimit() / setLimit()

Get and set the limit of the query.

getProject() / setProject()

Sets the projection of the criteria to state specific fields to include/omit.

getSelect() / setSelect()

These provide aliases for getProject() and setProject().

compare()

This works a lot like CDbCriterias and is heavily based on it.

You simply enter column, value and matchPartial parameter values (in that order) and the EMongoCriteria class will create a condition and merge it into your current condition based upon the entered data. As examples:

$c->compare('name', 'sammaye');

$c->compare('i', '<4');

The compare funtion, as seen in the second example, will accept a certain number of operators. The operators supported are: <>, <=, >=, <, >, =.

It is good to note that the function currently only accepts AND conditioning.

mergeWith()

Just like in CDbCriteria this merges either an array or another EMongoCriteria object into this one, transferring all of its properties.

As an example:

$c->mergeWith($otherC);

Now $c will have all the merged properties of $otherC.

toArray()

This basically will convert your EMongoCriteria into array form of the syntax:

array(
	'condition' => array(),
	'skip' => 1,
	'limit' => 1,
	'sort' => array(),
	'project' => array()
)

and, by default, is called like:

$c->toArray();

Covered and Partial Queries

When you do not wish to retrieve the entire document you can instead just return a partial result.

Both the EMongoCriteria and normal array based querying supports projection through two methods. First as a project variable in either EMongoCriteria:

$c->project=array('_id'=>0,'d'=>1);

Or as an element within the defined array (a scope as an example):

functions scope(){
	return array(
		'project' => array('_id'=>0,'d'=>1)
	);
}

And second, as a parameter injected into the read functions of the active record model, as an example:

User::model()->find(array(),array('_id'=>0,'d'=>1));

These will return partial=true EMongoDocument instances, either eagerly or in a cursor object. This specification is implemented within all currently existing read functions such as findOne and findBy_id and findByPk however, they are not accepted within the write functions (update, insert, save etc).

When a document is returned as partial it will only save the root level fields that are included within the result of the query.

Note: When using $elemMatch projection you must bare in mind that MongoYii will treat that result as the definitive result for that field. In other words when you go to save the root document MongoYii will consider that single projected subdocument the complete field value and will erase all other subdocuments within that field.

Note: If _id is omitted via '_id' => 0 from the root document then you will not be permitted to save the document at all. The extension will instead throw an exception about the _id field not being set.

GridFS

MongoYii has a GridFS handler called EMongoFile. This class is specifically designed as a helper and is in no way required in order to use GridFS with MongoYii. What it does is make it easy to upload, save and then retrieve files from GridFS. It is specifically oriented around uploading files from a form.

Let's go through an example of its usage as taken from the example in the test repository. To upload a new file from a form you simply call the populate static function on the class like so:

EMongoFile::populate($model,'avatar')

This essentially says: "Get the uploaded file from the model user and the field avatar" The rest works much the same as a normal upload form. If populate returns anything except null then it has found something.

To save the file to GridFS simply call save(). The class directly extends EMongoDocument as such this means that you have access to all the normal active record stuff as in other classes.

If you wish to add a validator for the file object itself you must point it to the file variable of the class; be sure to only allow validators for the file object on create otherwise Yii will not know how to handle the MongoGridFSFile object.

Note: Currently if you choose to call save on update it will overwrite the previous file. No versioning has been implemented.

Retreiving the file later is just as easy as saving it and is no different to finding any other record:

EMongoFile::model()->findOne(array('userId'=>Yii::app()->user->id))

This code snippet assumes we wish to find a file whose metadata field userId is of the current user in session.

Using urlManager

If you wish to regex out the _id within a URL for use with the urlManager you can use:

'<controller:\w+>/<action:\w+>/<id:[a-z0-9]{24}>'=>'<controller>/<action>',

Whereby it will try and pick out a alphanumeric _id of 24 characters in length.

Versioned Document Models

2.5.x of MongoYii adds the ability to version your documents.

If you are confused about versioning or how it can be beneficial for some scenarios then a well explained, yet simple and easy to read blog post can actually be found by the creators of MongoDB describing its addition to Mongoose.

To setup a versioned document you can simply create a model implementing version() which returns true and, optionally, versionField():

class versioned extends EMongoDocument{
	public versioned(){
		return true;
	}
	
	public versionField(){
		return '_v'; // This is actually the default value in EMongoDocument
	}
	
	public static function model($className=__CLASS__){
		return parent::model($className);
	}	
}

The verisoning ability of a document cannot be changed during runtime once it has been set, in other words you cannot do $doc->removeVersion() to stop versioning from having an effect for a certain insert.

After the documents model has been setup versioning works behind the scenes, there is no need for you to do anything else, everytime save is called it will make sure the version you have is upto date.

Known Flaws

• Subdocuments are not automated, however, I have stated why above
• the aggregation framework does not fit well with active record as such it is not directly supported within the models, however, there is an aggregate helper on each model but it will not return a model instance but instead the direct result of the MongoDB server response.

I am sure there are more but that is the immediate flaws you need to consider in this extension.

Bugs

Probably some, however, I will endeavour to accept pull requests and fix reported bugs.

Please report all issues, including bugs and/or questions, on the GitHub issue tracker.

Examples

Please look to the tests folder for further examples of how to use this extension, it is quite comprehensive.

There is also a demonstration application built using MongoYii. It is effectively mimicking a Wikipedia type website and allows for user (including sessions) and article management. It is not a good place to start if you are still learning Yii, however, it is a good place to start if you are learning MongoYii.

You can find the demonstration application repository here.

Running the Tests

The tests require the PHPUnit plugin with all dependencies compiled. Using PEAR you can initiate the following command:

sudo pear install --force --alldeps phpunit/PHPUnit &&
pear install phpunit/dbUnit &&
pear install phpunit/PHPUnit_Story &&
pear install phpunit/PHPUnit_Selenium &&
pear install phpunit/PHP_Invoker

After that you can just tell PHPUnit to run all tests within the tests/ folder with no real order.

Contributing

When adding extensive functionality to MongoYii please try and provide the corresponding unit tests. Without the unit tests your functionality, the very same your project most likely relies on, may break in future versions.

If you are intending to contribute changes to MongoYii I should explain my own position on the existance of the EMongoCriteria class. I, personally, believe it is not needed.

There are a number of reasons why. In SQL an abstraction is justified by, some but not all, of these reasons:

• Different implementations (i.e. MySQL and MSSQL and PostgreSQL) creates slightly different syntax
• SQL is a string based querying language as such it makes sense to have an object oriented abstraction layer
• SQL has some rather complex and difficult to form queries that would make an abstraction layer useful

MongoDB suffers from none of these problems; first it has an OO querying interface already, secondly it is easy to merge different queries together simply using CMap::MergeArray() and most of all it has only one syntax since MongoDB is only one database. On top of this, due to the way MongoDBs querying is built up this class can actually constrict your querying and make life a little harder and maybe even create unperformant queries (especially due to how difficult it is to do $ors in this class).

As such I believe that the EMongoCriteria class is just dead weight consuming memory which I could use for other tasks.

This extension does not rely on EMongoCriteria internally.

So I expect all modifications to certain parts of MongoYii to be compatible with and without EMongoCriteria.

Utilities

The util folder contains general awesome extensions to MongoYii that people may find useful. The sort of things that count as part of this folder are replacements for internal pieces of Yii that might seem outside of the scope of the root of this repository.

EMongoCache

This is a MongoYii implementation of CCache by Rajcs�nyi Zolt�n.

To use it first place it in your configuration:

'components'=>array(
	...
	'cache' => array(
		'class'=>'application.extensions.MongoYii.util.EMongoCache',
		// 'ensureIndex' => true, //set to false after first use of the cache
		// 'mongoConnectionId' => 'mongodb',
		// 'collectionName' => 'mongodb_cache',		
	),
}

The commented out lines are optional parameters you can send in if required.

And now an example of its usage:

// flush cache
Yii::app()->cache->flush();

// add data to cache
Yii::app()->cache->set('apple', 'fruit');
Yii::app()->cache->set('onion', 'vegetables');
Yii::app()->cache->set(1, 'one');
Yii::app()->cache->set(2, 'two');
Yii::app()->cache->set('one', 1);
Yii::app()->cache->set('two', 2);

// delete from cache
Yii::app()->cache->delete(1);
Yii::app()->cache->delete('two');

// read from cache
echo Yii::app()->cache->get(2);

// multiple read from cache
$arr = Yii::app()->cache->mget(array('apple', 1, 'two'));

print_r($arr); // Array( [apple] => fruit [1] => [two] => )

EMongoMessageSource

This is a MongoYii Yii::t() implementation by Rajcs�nyi Zolt�n.

To use it first add it to your configuration:

'components' => array(
	...
	'messages' => array(
		'class' => 'application.extensions.MongoYii.util.EMongoMessageSource',
		// 'mongoConnectionId' => 'mongodb', 
		// 'collectionName' => 'YiiMessages',               
	)        
)

The commented out lines are optional parameters you can send in if required.

And then add some messages to the translation table:

db.YiiMessages.insert( { category:"users", message:"Freund", translations: [ {language:"eng", message:"Friend"} ] } );

And then simply get that message:

<?=Yii::t('users', 'Freund'); ?>

EMongoSession

This is a MongoYii CHttpSession implementation by yours truly.

To use it simply include it in your configuration:

'session' => array(
	'class' => 'application.extensions.MongoYii.util.EMongoSession',
)

And use it as you would Yiis own normal session.

EMongoAuthManager

This is a MongoDB replacement for Yiis auth manager by @tvollstaedt.

To use it simply place it in your configuration:

'authManager' => array(
	'class' => 'EMongoAuthManager',
)

It will work the same way as any other auth manager.

Upgrade Notes

There has been a small but dramatic change between version 1.x and 2.x of MongoYii. The compare() function within the EMongoCriteria now no longer uses partial matching by default. This means that by default it will try and match the entire field value.

This change was implemented to match Yiis own behaviour. Yii, by default, will not match by LIKE when using this function.

This behaviour WILL NOT change here after. After complying to Yiis own behaviour it will be left alone.

Note: Only direct accession of compare() through EMongoCriteria is effected, no section of the extension relies on EMongoCriteria.

Versioning

This project uses semantic versioning 2.0.0.

Licence

This extension is licensed under the BSD 3 clause. To make it short and to the point: do whatever you want with it.