`Role.firstWhere()`

Get the first role matching a provided predicate.

Signature

Role.firstWhere(pred: (Role => Boolean)) => Role | Null

Description

Gets the first Role document that matches a provided predicate function.

Staged schema

If a database has staged schema, this method interacts with the database’s staged schema, not the active schema.

Parameters

Parameter Type Required Description

Parameter	Type	Required	Description
pred	Predicate function	Yes	Anonymous predicate function that: Accepts a `Role` document as its only argument. Supports shorthand-syntax. Returns a Boolean value. The method returns the first `Role` document for which the predicate returns true.

pred

Predicate function

Yes

Anonymous predicate function that:

Accepts a Role document as its only argument. Supports shorthand-syntax.
Returns a Boolean value.

The method returns the first Role document for which the predicate returns true.

Return value

One of:

Type Description

Type	Description
Role	First `Role` document that matches the predicate.
Null	No `Role` document matches the predicate.

Role

First Role document that matches the predicate.

Null

No Role document matches the predicate.

Examples

Role.firstWhere(.name.includes("manager"))

{
  name: "manager",
  coll: Role,
  ts: Time("2099-10-28T16:01:40.805Z"),
  privileges: [
    {
      resource: "OrderItem",
      actions: {
        create: true,
        read: true,
        write: true,
        delete: true
      }
    },
    {
      resource: "Customer",
      actions: {
        read: true
      }
    },
    {
      resource: "Manager",
      actions: {
        read: "(doc) => Query.identity() == doc && Date.today().dayOfWeek < 6"
      }
    },
    {
      resource: "getOrCreateCart",
      actions: {
        call: true
      }
    },
    {
      resource: "checkout",
      actions: {
        call: <<-END
          (args) => {
            let order = Order.byId(args[0])!
            order?.customer == Query.identity()
          }
        END
      }
    }
  ],
  membership: [
    {
      resource: "Manager"
    },
    {
      resource: "User",
      predicate: "(user) => user.accessLevel == \"manager\""
    }
  ]
}

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