Google Firestore - Access keys/values inside of an array/map in query

Question

I'm currently trying to access the information within a document here. I don't actually know what data structure that is. At first I thought it was an array, now a map, but maybe even key/value pairs?

The code I use to initalise it is:

$data = [
    'additional_email_info' => 'true',
    'address' => $addressData,
      ...
     ]

Where address is declared in the same way just before it. My current code to try to access the 'city' field:

$docRef = $db->collection('activities');
$query = $docRef->where('address', 'in', [$city_search]);
$documents = $query->documents();

I managed to retrieve information outside of address in the other fields, but I'm not sure how to access this field within the field and there is little documentation on it on their page here https://cloud.google.com/firestore/docs/query-data/queries .

Answer 1

If a field in a Firestore document has subfields, the value you get back when accessing that field is a dictionary/array. So you can access the city of a your example document with:

$docRef = $db->collection('activities');
$query = $docRef->where('address', 'in', [$city_search]);
$documents = $query->documents();

foreach ($documents as $city) {
    printf('Doc : %s' . PHP_EOL, $city->id());
    printf('Date: %s' . PHP_EOL, $city['date']);
    printf('City: %s' . PHP_EOL, $city['address']['city']);
    printf(PHP_EOL);
}

---

If you want to query on the city, you'd use dot notation :

$docRef->where('address.city', '=', 'London');