WriteBatch

class

A Firestore WriteBatch that can be used to atomically commit multiple write operations at once.

Methods

commit

commit() returns Promise containing Array of WriteResult

Atomically commits all pending operations to the database and verifies all preconditions. Fails the entire write if any precondition is not met.

Returns

Promise containing Array of WriteResult 

A Promise that resolves when this batch completes.

Example 

let writeBatch = firestore.batch();
let documentRef = firestore.doc('col/doc');

writeBatch.set(documentRef, {foo: 'bar'});

writeBatch.commit().then(() => {
  console.log('Successfully executed batch.');
});

create

create(documentRef, data) returns WriteBatch

Create a document with the provided object values. This will fail the batch if a document exists at its location.

Parameter

documentRef

DocumentReference

A reference to the document to be created.

data

DocumentData

The object to serialize as the document.
Returns

WriteBatch 

This WriteBatch instance. Used for chaining method calls.

Example 

let writeBatch = firestore.batch();
let documentRef = firestore.collection('col').doc();

writeBatch.create(documentRef, {foo: 'bar'});

writeBatch.commit().then(() => {
  console.log('Successfully executed batch.');
});

delete

delete(documentRef, precondition) returns WriteBatch

Deletes a document from the database.

Parameter

documentRef

DocumentReference

A reference to the document to be deleted.

precondition

Optional

Precondition

A precondition to enforce for this delete.

Values in precondition have the following properties:

Parameter

lastUpdateTime

Optional

string

If set, enforces that the document was last updated at lastUpdateTime (as ISO 8601 string). Fails the batch if the document doesn't exist or was last updated at a different time.

Returns

WriteBatch 

This WriteBatch instance. Used for chaining method calls.

Example 

let writeBatch = firestore.batch();
let documentRef = firestore.doc('col/doc');

writeBatch.delete(documentRef);

writeBatch.commit().then(() => {
  console.log('Successfully executed batch.');
});

set

set(documentRef, data, options) returns WriteBatch

Write to the document referred to by the provided DocumentReference. If the document does not exist yet, it will be created. If you pass SetOptions., the provided data can be merged into the existing document.

Parameter

documentRef

DocumentReference

A reference to the document to be set.

data

DocumentData

The object to serialize as the document.

options

Optional

SetOptions

An object to configure the set behavior.

Values in options have the following properties:

Parameter

merge

Optional

boolean

If true, set() only replaces the values specified in its data argument. Fields omitted from this set() call remain untouched.
Returns

WriteBatch 

This WriteBatch instance. Used for chaining method calls.

Example 

let writeBatch = firestore.batch();
let documentRef = firestore.doc('col/doc');

writeBatch.set(documentRef, {foo: 'bar'});

writeBatch.commit().then(() => {
  console.log('Successfully executed batch.');
});

update

update(documentRef, dataOrField, ...preconditionOrValues) returns WriteBatch

Update fields of the document referred to by the provided DocumentReference. If the document doesn't yet exist, the update fails and the entire batch will be rejected.

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.

Parameter

documentRef

DocumentReference

A reference to the document to be updated.

dataOrField

(UpdateData, string, or FieldPath)

An object containing the fields and values with which to update the document or the path of the first field to update.

preconditionOrValues

(Precondition, any type, string, or FieldPath)

An alternating list of field paths and values to update or a Precondition to restrict this update.

Value may be repeated.
Returns

WriteBatch 

This WriteBatch instance. Used for chaining method calls.

Example 

let writeBatch = firestore.batch();
let documentRef = firestore.doc('col/doc');

writeBatch.update(documentRef, {foo: 'bar'});

writeBatch.commit().then(() => {
  console.log('Successfully executed batch.');
});