A CollectionReference object can be used for adding documents, getting document references, and querying for documents (using the methods inherited from [Query] Query ).
CollectionReference Query
Package
@google-cloud/firestoreConstructors
(constructor)(firestore, path, converter)
constructor
(
firestore
:
Firestore
,
path
:
ResourcePath
,
converter
?:
firestore
.
FirestoreDataConverter<T>
);
Constructs a new instance of the CollectionReference
class
firestore
path
ResourcePath
The Path of this collection.
converter
FirebaseFirestore.FirestoreDataConverter
<T>
Properties
id
get
id
()
:
string
;
The last path element of the referenced collection.
{string} CollectionReference#id
let
collectionRef
=
firestore
.
collection
(
'col/doc/subcollection'
);
console
.
log
(
`ID of the subcollection:
${
collectionRef
.
id
}
`
);
parent
get
parent
()
:
DocumentReference<firestore
.
DocumentData
>
|
null
;
A reference to the containing Document if this is a subcollection, else null.
{DocumentReference|null} CollectionReference#parent
let
collectionRef
=
firestore
.
collection
(
'col/doc/subcollection'
);
let
documentRef
=
collectionRef
.
parent
;
console
.
log
(
`Parent name:
${
documentRef
.
path
}
`
);
path
get
path
()
:
string
;
A string representing the path of the referenced collection (relative to the root of the database).
{string} CollectionReference#path
let
collectionRef
=
firestore
.
collection
(
'col/doc/subcollection'
);
console
.
log
(
`Path of the subcollection:
${
collectionRef
.
path
}
`
);
Methods
add(data)
add
(
data
:
firestore
.
WithFieldValue<T>
)
:
Promise<DocumentReference<T>
> ;
Add a new document to this collection with the specified data, assigning it a document ID automatically.
data
FirebaseFirestore.WithFieldValue
<T>
An Object containing the data for the new document.
let
collectionRef
=
firestore
.
collection
(
'col'
);
collectionRef
.
add
({
foo
:
'bar'
}).
then
(
documentReference
=
>
{
console
.
log
(
`Added document with name:
${
documentReference
.
id
}
`
);
});
doc()
doc
()
:
DocumentReference<T>
;
doc(documentPath)
doc
(
documentPath
:
string
)
:
DocumentReference<T>
;
documentPath
string
isEqual(other)
isEqual
(
other
:
firestore
.
CollectionReference<T>
)
:
boolean
;
Returns true if this CollectionReference
is equal to the provided value.
other
FirebaseFirestore.CollectionReference
<T>
The value to compare against. {boolean} true if this CollectionReference
is equal to the provided value.
boolean
listDocuments()
listDocuments
()
:
Promise<Array<DocumentReference<T>
>> ;
Retrieves the list of documents in this collection.
The document references returned may include references to "missing documents", i.e. document locations that have no document present but which contain subcollections with documents. Attempting to read such a document reference (e.g. via .get()
or .onSnapshot()
) will return a DocumentSnapshot
whose .exists
property is false.
{Promise<DocumentReference[]>} The list of documents in this collection.
let
collectionRef
=
firestore
.
collection
(
'col'
);
return
collectionRef
.
listDocuments
().
then
(
documentRefs
=
>
{
return
firestore
.
getAll
(...
documentRefs
);
}).
then
(
documentSnapshots
=
>
{
for
(
let
documentSnapshot
of
documentSnapshots
)
{
if
(
documentSnapshot
.
exists
)
{
console
.
log
(
`Found document with data:
${
documentSnapshot
.
id
}
`
);
}
else
{
console
.
log
(
`Found missing document:
${
documentSnapshot
.
id
}
`
);
}
}
});
withConverter(converter)
withConverter
(
converter
:
null
)
:
CollectionReference<firestore
.
DocumentData
> ;
converter
null
withConverter(converter)
withConverter<U>
(
converter
:
firestore
.
FirestoreDataConverter<U>
)
:
CollectionReference<U>
;
converter
FirebaseFirestore.FirestoreDataConverter
<U>
U
