A reference to a transaction.
The Transaction object passed to a transaction's updateFunction provides the methods to read and write data within the transaction context. See [runTransaction()].
Transaction
Package
@google-cloud/firestoreConstructors
(constructor)(firestore, requestTag, transactionOptions)
constructor
(
firestore
:
Firestore
,
requestTag
:
string
,
transactionOptions
?:
firestore
.
ReadWriteTransactionOptions
|
firestore
.
ReadOnlyTransactionOptions
);
Constructs a new instance of the Transaction
class
firestore
requestTag
string
A unique client-assigned identifier for the scope of this transaction.
transactionOptions
FirebaseFirestore.ReadWriteTransactionOptions
| FirebaseFirestore.ReadOnlyTransactionOptions
The user-defined options for this transaction.
Methods
create(documentRef, data)
create<AppModelType
,
DbModelType
extends
firestore
.
DocumentData
> (
documentRef
:
firestore
.
DocumentReference<AppModelType
,
DbModelType
> ,
data
:
firestore
.
WithFieldValue<AppModelType>
)
:
Transaction
;
Create the document referred to by the provided [DocumentReference] DocumentReference . The operation will fail the transaction if a document exists at the specified location.
documentRef
FirebaseFirestore.DocumentReference
<AppModelType, DbModelType>
A reference to the document to be created.
data
FirebaseFirestore.WithFieldValue
<AppModelType>
The object data to serialize as the document.
{Transaction} This Transaction instance. Used for chaining method calls.
AppModelType
DbModelType
firestore
.
runTransaction
(
transaction
=
>
{
let
documentRef
=
firestore
.
doc
(
'col/doc'
);
return
transaction
.
get
(
documentRef
).
then
(
doc
=
>
{
if
(
!
doc
.
exists
)
{
transaction
.
create
(
documentRef
,
{
foo
:
'bar'
});
}
});
});
delete(documentRef, precondition)
delete
(
documentRef
:
DocumentReference<any
,
any
> ,
precondition
?:
firestore
.
Precondition
)
:
this
;
Deletes the document referred to by the provided [DocumentReference] DocumentReference .
documentRef
precondition
firestore.Precondition
A precondition to enforce for this delete.
this
{Transaction} This Transaction instance. Used for chaining method calls.
firestore
.
runTransaction
(
transaction
=
>
{
let
documentRef
=
firestore
.
doc
(
'col/doc'
);
transaction
.
delete
(
documentRef
);
return
Promise
.
resolve
();
});
get(query)
get<AppModelType
,
DbModelType
extends
firestore
.
DocumentData
> (
query
:
firestore
.
Query<AppModelType
,
DbModelType
> )
:
Promise<QuerySnapshot<AppModelType
,
DbModelType
>> ;
Retrieves a query result. Holds a pessimistic lock on all returned documents.
query
FirebaseFirestore.Query
<AppModelType, DbModelType>
A query to execute. {Promise
AppModelType
DbModelType
get(documentRef)
get<AppModelType
,
DbModelType
extends
firestore
.
DocumentData
> (
documentRef
:
firestore
.
DocumentReference<AppModelType
,
DbModelType
> )
:
Promise<DocumentSnapshot<AppModelType
,
DbModelType
>> ;
Reads the document referenced by the provided DocumentReference.
Holds a pessimistic lock on the returned document.
documentRef
FirebaseFirestore.DocumentReference
<AppModelType, DbModelType>
A reference to the document to be read. {Promise
AppModelType
DbModelType
get(aggregateQuery)
get<AppModelType
,
DbModelType
extends
firestore
.
DocumentData
,
AggregateSpecType
extends
firestore
.
AggregateSpec
> (
aggregateQuery
:
firestore
.
AggregateQuery<AggregateSpecType
,
AppModelType
,
DbModelType
> )
:
Promise<AggregateQuerySnapshot<AggregateSpecType
,
AppModelType
,
DbModelType
>> ;
Retrieves an aggregate query result. Holds a pessimistic lock on all documents that were matched by the underlying query.
aggregateQuery
FirebaseFirestore.AggregateQuery
<AggregateSpecType, AppModelType, DbModelType>
An aggregate query to execute. An AggregateQuerySnapshot for the retrieved data.
Promise
< AggregateQuerySnapshot
<AggregateSpecType, AppModelType, DbModelType>>
AppModelType
DbModelType
AggregateSpecType
getAll(documentRefsOrReadOptions)
getAll<AppModelType
,
DbModelType
extends
firestore
.
DocumentData
> (...
documentRefsOrReadOptions
:
Array<firestore
.
DocumentReference<AppModelType
,
DbModelType
>
|
firestore
.
ReadOptions
> )
:
Promise<Array<DocumentSnapshot<AppModelType
,
DbModelType
>>> ;
Retrieves multiple documents from Firestore. Holds a pessimistic lock on all returned documents.
The first argument is required and must be of type DocumentReference
followed by any additional DocumentReference
documents. If used, the optional ReadOptions
must be the last argument.
documentRefsOrReadOptions
Array
< FirebaseFirestore.DocumentReference
<AppModelType, DbModelType> | FirebaseFirestore.ReadOptions
>
The DocumentReferences
to receive, followed by an optional field mask.
Promise
< Array
< DocumentSnapshot
<AppModelType, DbModelType>>>
{Promise<Array.
AppModelType
DbModelType
let
firstDoc
=
firestore
.
doc
(
'col/doc1'
);
let
secondDoc
=
firestore
.
doc
(
'col/doc2'
);
let
resultDoc
=
firestore
.
doc
(
'col/doc3'
);
firestore
.
runTransaction
(
transaction
=
>
{
return
transaction
.
getAll
(
firstDoc
,
secondDoc
).
then
(
docs
=
>
{
transaction
.
set
(
resultDoc
,
{
sum
:
docs
[
0
].
get
(
'count'
)
+
docs
[
1
].
get
(
'count'
)
});
});
});
set(documentRef, data, options)
set<AppModelType
,
DbModelType
extends
firestore
.
DocumentData
> (
documentRef
:
firestore
.
DocumentReference<AppModelType
,
DbModelType
> ,
data
:
firestore
.
PartialWithFieldValue<AppModelType>
,
options
:
firestore
.
SetOptions
)
:
Transaction
;
documentRef
FirebaseFirestore.DocumentReference
<AppModelType, DbModelType>
data
FirebaseFirestore.PartialWithFieldValue
<AppModelType>
options
firestore.SetOptions
AppModelType
DbModelType
set(documentRef, data)
set<AppModelType
,
DbModelType
extends
firestore
.
DocumentData
> (
documentRef
:
firestore
.
DocumentReference<AppModelType
,
DbModelType
> ,
data
:
firestore
.
WithFieldValue<AppModelType>
)
:
Transaction
;
documentRef
FirebaseFirestore.DocumentReference
<AppModelType, DbModelType>
data
FirebaseFirestore.WithFieldValue
<AppModelType>
AppModelType
DbModelType
update(documentRef, dataOrField, preconditionOrValues)
update<AppModelType
,
DbModelType
extends
firestore
.
DocumentData
> (
documentRef
:
firestore
.
DocumentReference<AppModelType
,
DbModelType
> ,
dataOrField
:
firestore
.
UpdateData<DbModelType>
|
string
|
firestore
.
FieldPath
,
...
preconditionOrValues
:
Array<firestore
.
Precondition
|
unknown
|
string
|
firestore
.
FieldPath
> )
:
Transaction
;
Updates fields in the document referred to by the provided [DocumentReference] DocumentReference . The update will fail if applied to a document that does not exist.
The update() method accepts either an object with field paths encoded as keys and field values encoded as values, or a variable number of arguments that alternate between field paths and field values. Nested fields can be updated by providing dot-separated field path strings or by providing FieldPath objects.
A Precondition restricting this update can be specified as the last argument.
documentRef
FirebaseFirestore.DocumentReference
<AppModelType, DbModelType>
A reference to the document to be updated.
dataOrField
FirebaseFirestore.UpdateData
<DbModelType> | string | FirebaseFirestore.FieldPath
An object containing the fields and values with which to update the document or the path of the first field to update.
preconditionOrValues
Array
< FirebaseFirestore.Precondition
| unknown | string | FirebaseFirestore.FieldPath
>
An alternating list of field paths and values to update or a Precondition to to enforce on this update.
{Transaction} This Transaction instance. Used for chaining method calls.
AppModelType
DbModelType
firestore
.
runTransaction
(
transaction
=
>
{
let
documentRef
=
firestore
.
doc
(
'col/doc'
);
return
transaction
.
get
(
documentRef
).
then
(
doc
=
>
{
if
(
doc
.
exists
)
{
transaction
.
update
(
documentRef
,
{
count
:
doc
.
get
(
'count'
)
+
1
});
}
else
{
transaction
.
create
(
documentRef
,
{
count
:
1
});
}
});
});
