Make Block Configruation

Block/MyBlock: # name of the entity including subdirectory for all gereated files/classes. the subdirectory is optional.
    namespace: App # add Block files to a certain Bundle [optional]
    groups: # groups to use in block-config/type [optional]
        - layout
        - content
    label: 'Logowall' # the label to use in block-config/type [optional]
    block_type: true # generate block type [optional]
    use: # add use statements to Block entity
        - Doctrine\Common\Collections\Collection
        - Doctrine\Common\Collections\ArrayCollection
    form:
        use: # add use statements to Block FormType
            - Symfony\Component\Form\Extension\Core\Type\TextType

    properties: # a list of properties to be added to block/orm/form-type
        overline:
            type: string # the php data-type
            orm_type: string # can be used to have another type in ORM
            nullable: true # configure the property nullable in Block entity and ORM [optional]
            form:
                class: TextType # form type to be used
                options:
                    label: "'Overline'"
        layout:
            template: ChoiceType # use/create templates for complex types that are used multiple times
            form:
                options:
                    choices:
                        'Linksbündig': "'left'" # for ChoiceType choices you need to escape the keys also!
                        'Rechtsbündig': "'right'" # double AND single quotes to add string values!
                    expanded: 'true' # single OR double quotes to add boolean values!
        text:
            template: TextareaType

        children:
            type: ListType
            type_options:
                entry_class: MyBlockItem # means that adder/remover is generated
            relation: # defines the doctrine relation
                target_entity: MyBlockItem::class # target entity for the relation (entry_class but including namespace)
                mapped_by: myBlock # orm relation and also creates setMyBlock($this/null) in adder/remover
            form: # settings for the BlockFormType
                options: # form type options
                    entry_type: MyBlockItemType::class # no quotes to place value directly
                    label: "'Children'"

    classes: # you can create multiple related or non related entities here. config rules as read above.
        Block/MyBlockItem:
            properties:
                myBlock:
                    type: MyBlock
                    nullable: true
                    relation:
                        type: ManyToOne
                        target_entity: MyBlock::class
                        inversed_by: children
                position:
                    template: PositionType
                title:
                    template: TextType
                picture:
                    template: MediaType
                    form:
                        options:
                            label: "'Bild'"
                content:
                    template: BlockNodeType # Blocks that also contain other Blocks
                    form:
                        options:
                            label: "'Logowall-Item-Content'"
                            item_groups: "['logowall']" # groups to be loaded into BlockNodeType
                files:
                    template: MediaTypeMultiple # multiple files