Laravel Many to Many (3 and 3+ Models) Design Questions - laravel

Question

I have got three models
Contacts Model
Contact Roles Model
Project Model
Set up;
contacts can belong to multiple projects. (Many to Many)
each project has its own contact roles created by user. (One to Many - Roles are specific to projects)
Within selected project, a contact can be assigned to multiple roles (Many to many)
Tricky part is I have categories for roles model, when user is creating the role, they select a category for that role from a dropdown(from a db, total of 7 predefined categories).
Then what I try to do and have issue with understanding;
1.What is the best way to display all contacts with given roles on that specific project?
I can easily get $project->contacts() //this gives me all contacts within that projectbut I need to one step further, where I can get contacts with their roles.
2.Furthermore, how would I display all contacts that are part of that selected category for that project?
3.Should i be using a different connection between my models other than many to many, like has many through ?

Answer 1

Assumption - with
display
you actually mean retrieve with eloquent.
Word of advice - READ THE DOCS! Laravel has great and easy to understand documentation.
https://laravel.com/docs/5.7/eloquent-relationships#eager-loading
1) I can easily get $project->contacts() //this gives me all contacts within that projectbut I need to one step further, where I can get contacts with their roles.
Nested eager loading:
$project = Project::with('contacts.roles')->find($id);
2) Furthermore, how would I display all contacts that are part of that selected category for that project?
Constraining eager loads and querying relationship existance:
$project = Project::with(['contacts', function($q) use ($categoryId) {
$q->with('roles')->whereHas(['category' => function($q2) use ($categoryId) {
$q2->whereId($categoryId);
});
}]);
3.Should i be using a different connection between my models other than many to many, like has many through ?
Structure looks fine to me.