LARAVEL: One-to-one relationship on a pivot table? - laravel

Question

I can't think of how to handle this in Eloquent. I have a many-to-many relationship that needs a one-to-one relationship assigned to it.
Here is the basic database structure I designed in its simplest form:
ACCOUNTS: id
AGENTS: id
FEES: id
ACCOUNT_AGENT: account_id, agent_id, fee_id
Each Account belongsToMany Agents.
Each Agent belongsToMany Accounts.
Each "Account_Agent" (the many-to-many pivot table) belongsTo Fee.
How do I define that third relationship in an Eloquent model?
I want to be able to access the "account_agent" fee like this (or similar):
$account = Account::first();
foreach ($account->agents as $agent) {
echo $agent->fee;
}
Thanks, hopefully my question is clear.

Answer 1

See here:
https://laravel.com/docs/5.4/eloquent-relationships#many-to-many
Scroll down to Defining Custom Intermediate Table Models
Basically what you have to do is to define a class like this:
class AccountAgent extends Illuminate\Database\Eloquent\Relations\Pivot
{
/**
* Many:1 relationship with Fee model
*
* #return \Illuminate\Database\Eloquent\Relations\BelongsTo
*/
public function fee()
{
return $this->belongsTo(Fee::class);
}
}
Then you define your many:many relationship in your Account class like this:
/**
* The agents that belong to the account.
*/
public function agents()
{
return $this->belongsToMany(Agent::class)->using(AccountAgent::class);
}
Then in your code, instead of this:
foreach ($account->agents as $agent) {
echo $agent->fee;
}
... do this:
foreach ($account->agents as $agent) {
/** #var Fee $fee_object */
$fee_object = $agent->pivot->fee;
}
In that loop $fee_object is of class Fee (the model class that covers the fees table) so you could echo $fee_object->fee_amount or whatever other columns you need to use.