Query Signals#

Query signals in TeamPlay represent the result of a query on a collection. They are created using the sub() function or useSub() hook with query parameters.

Creating a Query Signal#

const $activeUsers = await sub($.users, { status: 'active' })

Properties and Methods#

ids#

A signal containing an array of IDs for the documents in the query result.

const userIds = $activeUsers.ids.get()

map(callback)#

Maps over the documents in the query result.

const userNames = $activeUsers.map($user => $user.name.get())

reduce(callback, initialValue)#

Reduces the documents in the query result to a single value.

const totalAge = $activeUsers.reduce(($user, total) => total + $user.age.get(), 0)

find(predicate)#

Finds the first document in the query result that satisfies the predicate.

const $firstAdminUser = $activeUsers.find($user => $user.role.get() === 'admin')

Iteration#

Query signals are iterable, allowing you to use them in for...of loops:

for (const $user of $activeUsers) {
  console.log($user.name.get())
}

Notes#

• Query signals are reactive. Changes to the underlying data or to the query result will automatically update components using the query signal.
• The documents within a query signal are themselves signals, allowing for nested reactivity.