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POMVC: How to work with entities with many child entities?
 

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  1. POMVC: How to work with entities with many child entities?
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    <p>In the current examples on ASP.NET MVC I see quite basic entities, with simple CRUD methods.<br> But I'm not sure about what to do with more advanced models. Let me give an example:</p> <p>We have a garage website. The garage has:</p> <ul> <li>Inventory with <code>carparts</code></li> <li><code>Employees</code></li> <li><code>Customers</code></li> <li><code>Cars</code> that consists of all cars that are/were in the garage</li> </ul> <p>Now lets take the <code>car</code>, the car might have a collection of <code>employees</code> that worked on the car (derived from the original <code>employee</code> class, adds some extra props that tie him to the car), a collection of <code>carparts</code> that have been replaced (also derived, adds for example SerialNr, and <code>ReplacementDate</code> prop) , and of course a <code>customer</code> prop of the customer whoe owns the car.</p> <p>Now in <code>rest</code> I would like to see the following:</p> <pre><code>/cars/423 [get] //show car # 423 /cars/423/edit [get] //shows the edit form (ajax enabled, so also shows the other props) /cars/423/carparts [get] //gets the carparts inside the car /cars/423/carparts/32/edit [post] //updates that specific carpart inside the specific car /cars/423/employees [get] //gets the employees who worked on the car /inventory [get] /inventory/1234/edit [get] //gets the update form for carpart with ID 1234 /employees [get] //gets all the employees in the company </code></pre> <p>So how would I build my Controllers? Should I add all those CRUD methods for the child elements inside the <code>CarsController</code>? Doesn't that make a very fat controller because of the tens of methods (this model is overly simplified, the car has many more parent-child relationships)? Or should I create a <code>EmployeesInCar</code> controller (seems bad)... Thanks a lot.</p> <p><strong>EDIT:</strong><br> First of all the example is hypothetical only, just an example.<br> If I follow the suggestion I would have a <code>CarController</code> which only handles cars. And my PartsController would handle only Parts. But we have two sets of <code>Part</code>s, a general one (for the inventory); and we have a <code>Part</code> inside a car, which derives from the general one, but adds properties such as <code>SerialNumber</code> and <code>ReplacementDate</code>.<br> So my Parts controller becomes quite fat, for the example let's call the entities: GeneralPart (in inventory) and SpecificPart (the derived class, with the extra properties)</p> <pre><code>Index -&gt; Returns all GeneralParts in inventory. IndexByCar(int id) -&gt; Return all SpecificParts by Car. etc. etc. </code></pre> <p>Because each action deals with either a General Part or a Specific Part. The same is for employees, we have the base employee class, and a specific one, with extra properties.</p>
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    1. COInteresting question (+1)
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    2. COThis is a great question, that the official tutorials certainly do not seem to discuss.
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