I have got a problem to build a forms with many relations between tables. The structure of relations you can see on below picture:
My relations in YML:
######### Products.orm.yml #########
type: entity
table: products
fields:
...
lifecycleCallbacks: { }
oneToMany:
productCombinations:
targetEntity: ProductsCombinations
mappedBy: product
######### ProductsCombinations.orm.yml #########
type: entity
table: products_combinations
fields:
...
lifecycleCallbacks: { }
oneToMany:
productAttributes:
targetEntity: ProductsAttributesJoin
mappedBy: productCombinations
manyToOne:
product:
targetEntity: Products
inversedBy: productCombinations
joinColumn:
name: product_id
referencedColumnName: id
######### ProductsAttributesJoin.orm.yml ########
type: entity
table: null
fields:
combinationID:
type: bigint
column: combination_id
id: true
generator:
strategy: NONE
attributeID:
type: bigint
id: true
generator:
strategy: NONE
column: attribute_id
lifecycleCallbacks: { }
manyToOne:
productCombinations:
targetEntity: ProductsCombinations
inversedBy: productAttributes
joinColumn:
name: combination_id
referencedColumnName: combination_id
attributes:
targetEntity: Attributes
inversedBy: productAttributesJoin
joinColumn:
name: attribute_id
referencedColumnName: id
######### Attributes.orm.yml #########
type: entity
table: products_attributes
fields:
...
lifecycleCallbacks: { }
oneToMany:
productAttributesJoin:
targetEntity: ProductsAttributesJoin
mappedBy: attributes
manyToOne:
productAttributesDefinitions:
targetEntity: AttributesDefinitions
inversedBy: productAttributes
joinColumn:
name: attribute_id
referencedColumnName: id
######### AttributesDefinitions.orm.yml #########
type: entity
table: products_attributes_definitions
fields:
...
lifecycleCallbacks: { }
oneToMany:
productAttributes:
targetEntity: Attributes
mappedBy: productAttributesDefinitions
manyToOne:
productAttributesDefinitions:
targetEntity: AttributesDefinitions
inversedBy: productAttributes
joinColumn:
name: attribute_id
referencedColumnName: id
What I have got know is that:

What is not working as when I will click Add new then I got popup with fields from ProductsCombinations but when I will fill them in and press Save then it is showing error that product_id is null (but it should take it from Products).
Also what I would like to do is something like that:

Also a bit of code from Admin directory:
###### ProductsView.php ######
$formMapper->with('Attributes')
->add('productCombinations', 'sonata_type_collection')
->end()
###### ProductsCombinations.php ######
$formMapper
->with('General')
->(some main fields from productCombinations)
->add('productAttributes', 'sonata_type_collection', array(), array(
'edit' => 'inline',
'inline' => 'table',
'sortable' => 'position'
))
###### ProductsAttributesJoin.php ######
$formMapper
->with('General')
->add('attributes', 'sonata_type_model')
->end()
;