Add data to Cloud Firestore

This document explains how to set, add, or update individual documents in Cloud Firestore. To write data in bulk, see Transactions and batched writes.

Overview

You can write data to Cloud Firestore in one of the following ways:

• Set the data of a document within a collection, explicitly specifying a document identifier.
• Add a new document to a collection. In this case, Cloud Firestore automatically generates the document identifier.
• Create an empty document with an automatically generated identifier, and assign data to it later.

Note: While the code samples cover multiple languages, the text explaining the samples refers to the Web method names.

Before you begin

Before you can initialize Cloud Firestore to set, add, or update data, you must complete the following steps:

• Create a Cloud Firestore database. For more information, see Get started with Cloud Firestore
• If you use the web or mobile client libraries, authenticate with security rules. For more information, see Getting started with security rules.
• If you use the server client libraries or REST API, authenticate with Identity and Access Management (IAM). For more information, see Security for server client libraries.

Initialize Cloud Firestore

Initialize an instance of Cloud Firestore:

Web

import { initializeApp } from "firebase/app";
import { getFirestore } from "firebase/firestore";

// TODO: Replace the following with your app's Firebase project configuration
// See: https://support.google.com/firebase/answer/7015592
const firebaseConfig = {
    FIREBASE_CONFIGURATION
};

// Initialize Firebase
const app = initializeApp(firebaseConfig);


// Initialize Cloud Firestore and get a reference to the service
const db = getFirestore(app);

Replace FIREBASE_CONFIGURATION with your web app's firebaseConfig.

To persist data when the device loses its connection, see the Enable Offline Data documentation.

Web

import firebase from "firebase/app";
import "firebase/firestore";

// TODO: Replace the following with your app's Firebase project configuration
// See: https://support.google.com/firebase/answer/7015592
const firebaseConfig = {
    FIREBASE_CONFIGURATION
};

// Initialize Firebase
firebase.initializeApp(firebaseConfig);


// Initialize Cloud Firestore and get a reference to the service
const db = firebase.firestore();

Replace FIREBASE_CONFIGURATION with your web app's firebaseConfig.

To persist data when the device loses its connection, see the Enable Offline Data documentation.

Swift

Note: This product is not available on watchOS and App Clip targets.

import FirebaseCore
import FirebaseFirestore

FirebaseApp.configure()

let db = Firestore.firestore()
AppDelegate.swift

Objective-C

Note: This product is not available on watchOS and App Clip targets.

@import FirebaseCore;
@import FirebaseFirestore;

// Use Firebase library to configure APIs
[FIRApp configure];
  

FIRFirestore *defaultFirestore = [FIRFirestore firestore];
AppDelegate.m

Kotlin+KTX

// Access a Cloud Firestore instance from your Activity

val db = Firebase.firestore
DocSnippets.kt

Java

// Access a Cloud Firestore instance from your Activity

FirebaseFirestore db = FirebaseFirestore.getInstance();
DocSnippets.java

Dart

db = FirebaseFirestore.instance;

Java

The Cloud Firestore SDK is initialized in different ways depending on your environment. Below are the most common methods. For a complete reference, see Initialize the Admin SDK.

Initialize on Google Cloud

import com.google.auth.oauth2.GoogleCredentials;
import com.google.cloud.firestore.Firestore;

import com.google.firebase.FirebaseApp;
import com.google.firebase.FirebaseOptions;

// Use the application default credentials
GoogleCredentials credentials = GoogleCredentials.getApplicationDefault();
FirebaseOptions options = new FirebaseOptions.Builder()
    .setCredentials(credentials)
    .setProjectId(projectId)
    .build();
FirebaseApp.initializeApp(options);

Firestore db = FirestoreClient.getFirestore();

Initialize on your own server

To use the Firebase Admin SDK on your own server, use a service account.

Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:

import com.google.auth.oauth2.GoogleCredentials;
import com.google.cloud.firestore.Firestore;

import com.google.firebase.FirebaseApp;
import com.google.firebase.FirebaseOptions;

// Use a service account
InputStream serviceAccount = new FileInputStream("path/to/serviceAccount.json");
GoogleCredentials credentials = GoogleCredentials.fromStream(serviceAccount);
FirebaseOptions options = new FirebaseOptions.Builder()
    .setCredentials(credentials)
    .build();
FirebaseApp.initializeApp(options);

Firestore db = FirestoreClient.getFirestore();

Python

The Cloud Firestore SDK is initialized in different ways depending on your environment. Below are the most common methods. For a complete reference, see Initialize the Admin SDK.

Initialize on Google Cloud

import firebase_admin
from firebase_admin import firestore

# Application Default credentials are automatically created.
app = firebase_admin.initialize_app()
db = firestore.client()
firestore.py

An existing application default credential can also be used to initialize the SDK.

import firebase_admin
from firebase_admin import credentials
from firebase_admin import firestore

# Use the application default credentials.
cred = credentials.ApplicationDefault()

firebase_admin.initialize_app(cred)
db = firestore.client()
firestore.py

Initialize on your own server

To use the Firebase Admin SDK on your own server, use a service account.

Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:

import firebase_admin
from firebase_admin import credentials
from firebase_admin import firestore

# Use a service account.
cred = credentials.Certificate('path/to/serviceAccount.json')

app = firebase_admin.initialize_app(cred)

db = firestore.client()
firestore.py

Python

The Cloud Firestore SDK is initialized in different ways depending on your environment. Below are the most common methods. For a complete reference, see Initialize the Admin SDK.

Initialize on Google Cloud

import firebase_admin
from firebase_admin import firestore_async

# Application Default credentials are automatically created.
app = firebase_admin.initialize_app()
db = firestore_async.client()
firestore_async.py

An existing application default credential can also be used to initialize the SDK.

import firebase_admin
from firebase_admin import credentials
from firebase_admin import firestore_async

# Use the application default credentials.
cred = credentials.ApplicationDefault()

firebase_admin.initialize_app(cred)
db = firestore_async.client()
firestore_async.py

Initialize on your own server

To use the Firebase Admin SDK on your own server, use a service account.

Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:

import firebase_admin
from firebase_admin import credentials
from firebase_admin import firestore_async

# Use a service account.
cred = credentials.Certificate('path/to/serviceAccount.json')

app = firebase_admin.initialize_app(cred)

db = firestore_async.client()
firestore_async.py

C++

// Make sure the call to `Create()` happens some time before you call Firestore::GetInstance().
App::Create();
Firestore* db = Firestore::GetInstance();
AppDelegate.mm

Node.js

The Cloud Firestore SDK is initialized in different ways depending on your environment. Below are the most common methods. For a complete reference, see Initialize the Admin SDK.

• Initialize on Cloud Functions

  const { initializeApp, applicationDefault, cert } = require('firebase-admin/app');
  const { getFirestore, Timestamp, FieldValue, Filter } = require('firebase-admin/firestore');

  initializeApp();
  
  const db = getFirestore();
  index.js

• Initialize on Google Cloud

  const { initializeApp, applicationDefault, cert } = require('firebase-admin/app');
  const { getFirestore, Timestamp, FieldValue, Filter } = require('firebase-admin/firestore');

  initializeApp({
    credential: applicationDefault()
  });
  
  const db = getFirestore();
  index.js

• Initialize on your own server

  To use the Firebase Admin SDK on your own server (or any other Node.js environment), use a service account. Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:

  const { initializeApp, applicationDefault, cert } = require('firebase-admin/app');
  const { getFirestore, Timestamp, FieldValue, Filter } = require('firebase-admin/firestore');

  const serviceAccount = require('./path/to/serviceAccountKey.json');
  
  initializeApp({
    credential: cert(serviceAccount)
  });
  
  const db = getFirestore();
  index.js

Go

The Cloud Firestore SDK is initialized in different ways depending on your environment. Below are the most common methods. For a complete reference, see Initialize the Admin SDK.

Initialize on Google Cloud

import (
  "log"

  firebase "firebase.google.com/go"
  "google.golang.org/api/option"
)

// Use the application default credentials
ctx := context.Background()
conf := &firebase.Config{ProjectID: projectID}
app, err := firebase.NewApp(ctx, conf)
if err != nil {
  log.Fatalln(err)
}

client, err := app.Firestore(ctx)
if err != nil {
  log.Fatalln(err)
}
defer client.Close()

Initialize on your own server

To use the Firebase Admin SDK on your own server, use a service account.

Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:

import (
  "log"

  firebase "firebase.google.com/go"
  "google.golang.org/api/option"
)

// Use a service account
ctx := context.Background()
sa := option.WithCredentialsFile("path/to/serviceAccount.json")
app, err := firebase.NewApp(ctx, nil, sa)
if err != nil {
  log.Fatalln(err)
}

client, err := app.Firestore(ctx)
if err != nil {
  log.Fatalln(err)
}
defer client.Close()

PHP

PHP

For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.

use Google\Cloud\Firestore\FirestoreClient;

/**
 * Initialize Cloud Firestore with default project ID.
 */
function setup_client_create(string $projectId = null)
{
    // Create the Cloud Firestore client
    if (empty($projectId)) {
        // The `projectId` parameter is optional and represents which project the
        // client will act on behalf of. If not supplied, the client falls back to
        // the default project inferred from the environment.
        $db = new FirestoreClient();
        printf('Created Cloud Firestore client with default project ID.' . PHP_EOL);
    } else {
        $db = new FirestoreClient([
            'projectId' => $projectId,
        ]);
        printf('Created Cloud Firestore client with project ID: %s' . PHP_EOL, $projectId);
    }
}
setup_client_create.php

Unity

using Firebase.Firestore;
using Firebase.Extensions;

FirebaseFirestore db = FirebaseFirestore.DefaultInstance;

C#

C#

For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.

FirestoreDb db = FirestoreDb.Create(project);
Console.WriteLine("Created Cloud Firestore client with project ID: {0}", project);
Program.cs

Ruby

require "google/cloud/firestore"

# The `project_id` parameter is optional and represents which project the
# client will act on behalf of. If not supplied, the client falls back to the
# default project inferred from the environment.
firestore = Google::Cloud::Firestore.new project_id: project_id

puts "Created Cloud Firestore client with given project ID."
quickstart.rb

Set a document

To create or overwrite a single document, use the following language-specific set() methods:

Web

Use the setDoc() method:

import { doc, setDoc } from "firebase/firestore"; 

// Add a new document in collection "cities"
await setDoc(doc(db, "cities", "LA"), {
  name: "Los Angeles",
  state: "CA",
  country: "USA"
});
set_document.js

Web

Use the set() method:

// Add a new document in collection "cities"
db.collection("cities").doc("LA").set({
    name: "Los Angeles",
    state: "CA",
    country: "USA"
})
.then(() => {
    console.log("Document successfully written!");
})
.catch((error) => {
    console.error("Error writing document: ", error);
});
test.firestore.js

Swift

Use the setData() method:

Note: This product is not available on watchOS and App Clip targets.

// Add a new document in collection "cities"
do {
  try await db.collection("cities").document("LA").setData([
    "name": "Los Angeles",
    "state": "CA",
    "country": "USA"
  ])
  print("Document successfully written!")
} catch {
  print("Error writing document: \(error)")
}
ViewController.swift

Objective-C

Use the setData: method:

Note: This product is not available on watchOS and App Clip targets.

// Add a new document in collection "cities"
[[[self.db collectionWithPath:@"cities"] documentWithPath:@"LA"] setData:@{
  @"name": @"Los Angeles",
  @"state": @"CA",
  @"country": @"USA"
} completion:^(NSError * _Nullable error) {
  if (error != nil) {
    NSLog(@"Error writing document: %@", error);
  } else {
    NSLog(@"Document successfully written!");
  }
}];
ViewController.m

Kotlin+KTX

Use the set() method:

val city = hashMapOf(
    "name" to "Los Angeles",
    "state" to "CA",
    "country" to "USA",
)

db.collection("cities").document("LA")
    .set(city)
    .addOnSuccessListener { Log.d(TAG, "DocumentSnapshot successfully written!") }
    .addOnFailureListener { e -> Log.w(TAG, "Error writing document", e) }
DocSnippets.kt

Java

Use the set() method:

Map<String, Object> city = new HashMap<>();
city.put("name", "Los Angeles");
city.put("state", "CA");
city.put("country", "USA");

db.collection("cities").document("LA")
        .set(city)
        .addOnSuccessListener(new OnSuccessListener<Void>() {
            @Override
            public void onSuccess(Void aVoid) {
                Log.d(TAG, "DocumentSnapshot successfully written!");
            }
        })
        .addOnFailureListener(new OnFailureListener() {
            @Override
            public void onFailure(@NonNull Exception e) {
                Log.w(TAG, "Error writing document", e);
            }
        });
DocSnippets.java

Dart

Use the set() method:

final city = <String, String>{
  "name": "Los Angeles",
  "state": "CA",
  "country": "USA"
};

db
    .collection("cities")
    .doc("LA")
    .set(city)
    .onError((e, _) => print("Error writing document: $e"));
firestore.dart

Java

Use the set() method:

// Create a Map to store the data we want to set
Map<String, Object> docData = new HashMap<>();
docData.put("name", "Los Angeles");
docData.put("state", "CA");
docData.put("country", "USA");
docData.put("regions", Arrays.asList("west_coast", "socal"));
// Add a new document (asynchronously) in collection "cities" with id "LA"
ApiFuture<WriteResult> future = db.collection("cities").document("LA").set(docData);
// ...
// future.get() blocks on response
System.out.println("Update time : " + future.get().getUpdateTime());
ManageDataSnippets.java

Python

Use the set() method:

data = {"name": "Los Angeles", "state": "CA", "country": "USA"}

# Add a new doc in collection 'cities' with ID 'LA'
db.collection("cities").document("LA").set(data)
snippets.py

Python

Use the set() method:

data = {"name": "Los Angeles", "state": "CA", "country": "USA"}

# Add a new doc in collection 'cities' with ID 'LA'
await db.collection("cities").document("LA").set(data)
snippets.py

C++

Use the Set() method:

// Add a new document in collection 'cities'
db->Collection("cities")
    .Document("LA")
    .Set({{"name", FieldValue::String("Los Angeles")},
          {"state", FieldValue::String("CA")},
          {"country", FieldValue::String("USA")}})
    .OnCompletion([](const Future<void>& future) {
      if (future.error() == Error::kErrorOk) {
        std::cout << "DocumentSnapshot successfully written!" << std::endl;
      } else {
        std::cout << "Error writing document: " << future.error_message()
                  << std::endl;
      }
    });
snippets.cpp

Node.js

Use the set() method:

const data = {
  name: 'Los Angeles',
  state: 'CA',
  country: 'USA'
};

// Add a new document in collection "cities" with ID 'LA'
const res = await db.collection('cities').doc('LA').set(data);
index.js

Go

Use the Set() method:

import (
	"context"
	"log"

	"cloud.google.com/go/firestore"
)

func addDocAsMap(ctx context.Context, client *firestore.Client) error {
	_, err := client.Collection("cities").Doc("LA").Set(ctx, map[string]interface{}{
		"name":    "Los Angeles",
		"state":   "CA",
		"country": "USA",
	})
	if err != nil {
		// Handle any errors in an appropriate way, such as returning them.
		log.Printf("An error has occurred: %s", err)
	}

	return err
}
save_data_set_from_map.go

PHP

Use the set() method:

PHP

For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.

$data = [
    'name' => 'Los Angeles',
    'state' => 'CA',
    'country' => 'USA'
];
$db->collection('samples/php/cities')->document('LA')->set($data);
data_set_from_map.php

Unity

Use the SetAsync() method:

DocumentReference docRef = db.Collection("cities").Document("LA");
Dictionary<string, object> city = new Dictionary<string, object>
{
	{ "Name", "Los Angeles" },
	{ "State", "CA" },
	{ "Country", "USA" }
};
docRef.SetAsync(city).ContinueWithOnMainThread(task => {
	Debug.Log("Added data to the LA document in the cities collection.");
});

C#

Use the SetAsync() method:

DocumentReference docRef = db.Collection("cities").Document("LA");
Dictionary<string, object> city = new Dictionary<string, object>
{
    { "name", "Los Angeles" },
    { "state", "CA" },
    { "country", "USA" }
};
await docRef.SetAsync(city);
Program.cs

Ruby

Use the set() method:

city_ref = firestore.doc "#{collection_path}/LA"

data = {
  name:    "Los Angeles",
  state:   "CA",
  country: "USA"
}

city_ref.set data
add_data.rb

If the document does not exist, it will be created. If the document does exist, its contents will be overwritten with the newly provided data, unless you specify that the data should be merged into the existing document, as follows:

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

import { doc, setDoc } from "firebase/firestore"; 

const cityRef = doc(db, 'cities', 'BJ');
setDoc(cityRef, { capital: true }, { merge: true });
set_with_merge.js

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

var cityRef = db.collection('cities').doc('BJ');

var setWithMerge = cityRef.set({
    capital: true
}, { merge: true });
test.firestore.js

Swift

Note: This product is not available on watchOS and App Clip targets.

// Update one field, creating the document if it does not exist.
db.collection("cities").document("BJ").setData([ "capital": true ], merge: true)
ViewController.swift

Objective-C

Note: This product is not available on watchOS and App Clip targets.

// Write to the document reference, merging data with existing
// if the document already exists
[[[self.db collectionWithPath:@"cities"] documentWithPath:@"BJ"]
     setData:@{ @"capital": @YES }
     merge:YES
     completion:^(NSError * _Nullable error) {
       // ...
     }];
ViewController.m

Kotlin+KTX

// Update one field, creating the document if it does not already exist.
val data = hashMapOf("capital" to true)

db.collection("cities").document("BJ")
    .set(data, SetOptions.merge())
DocSnippets.kt

Java

// Update one field, creating the document if it does not already exist.
Map<String, Object> data = new HashMap<>();
data.put("capital", true);

db.collection("cities").document("BJ")
        .set(data, SetOptions.merge());
DocSnippets.java

Dart

// Update one field, creating the document if it does not already exist.
final data = {"capital": true};

db.collection("cities").doc("BJ").set(data, SetOptions(merge: true));
firestore.dart

Java

// asynchronously update doc, create the document if missing
Map<String, Object> update = new HashMap<>();
update.put("capital", true);

ApiFuture<WriteResult> writeResult =
    db.collection("cities").document("BJ").set(update, SetOptions.merge());
// ...
System.out.println("Update time : " + writeResult.get().getUpdateTime());
ManageDataSnippets.java

Python

city_ref = db.collection("cities").document("BJ")

city_ref.set({"capital": True}, merge=True)
snippets.py

Python

city_ref = db.collection("cities").document("BJ")

await city_ref.set({"capital": True}, merge=True)
snippets.py

C++

db->Collection("cities").Document("BJ").Set(
    {{"capital", FieldValue::Boolean(true)}}, SetOptions::Merge());
snippets.cpp

Node.js

const cityRef = db.collection('cities').doc('BJ');

const res = await cityRef.set({
  capital: true
}, { merge: true });
index.js

Go

import (
	"context"
	"log"

	"cloud.google.com/go/firestore"
)

func updateDocCreateIfMissing(ctx context.Context, client *firestore.Client) error {
	_, err := client.Collection("cities").Doc("BJ").Set(ctx, map[string]interface{}{
		"capital": true,
	}, firestore.MergeAll)

	if err != nil {
		// Handle any errors in an appropriate way, such as returning them.
		log.Printf("An error has occurred: %s", err)
	}

	return err
}
save_data_set_doc_upsert.go

PHP

PHP

For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.

$cityRef = $db->collection('samples/php/cities')->document('BJ');
$cityRef->set([
    'capital' => true
], ['merge' => true]);
data_set_doc_upsert.php

Unity

DocumentReference docRef = db.Collection("cities").Document("LA");
Dictionary<string, object> update = new Dictionary<string, object>
{
	{ "capital", false }
};
docRef.SetAsync(update, SetOptions.MergeAll);

C#

DocumentReference docRef = db.Collection("cities").Document("LA");
Dictionary<string, object> update = new Dictionary<string, object>
{
    { "capital", false }
};
await docRef.SetAsync(update, SetOptions.MergeAll);
Program.cs

Ruby

city_ref = firestore.doc "#{collection_path}/LA"
city_ref.set({ capital: false }, merge: true)
add_data.rb

If you're not sure whether the document exists, pass the option to merge the new data with any existing document to avoid overwriting entire documents. For documents that contain maps, if you specify a set with a field that contains an empty map, the map field of the target document is overwritten.

Data types

Cloud Firestore lets you write a variety of data types inside a document, including strings, booleans, numbers, dates, null, and nested arrays and objects. Cloud Firestore always stores numbers as doubles, regardless of what type of number you use in your code.

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

import { doc, setDoc, Timestamp } from "firebase/firestore"; 

const docData = {
    stringExample: "Hello world!",
    booleanExample: true,
    numberExample: 3.14159265,
    dateExample: Timestamp.fromDate(new Date("December 10, 1815")),
    arrayExample: [5, true, "hello"],
    nullExample: null,
    objectExample: {
        a: 5,
        b: {
            nested: "foo"
        }
    }
};
await setDoc(doc(db, "data", "one"), docData);
data_types.js

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

var docData = {
    stringExample: "Hello world!",
    booleanExample: true,
    numberExample: 3.14159265,
    dateExample: firebase.firestore.Timestamp.fromDate(new Date("December 10, 1815")),
    arrayExample: [5, true, "hello"],
    nullExample: null,
    objectExample: {
        a: 5,
        b: {
            nested: "foo"
        }
    }
};
db.collection("data").doc("one").set(docData).then(() => {
    console.log("Document successfully written!");
});
test.firestore.js

Swift

Note: This product is not available on watchOS and App Clip targets.

let docData: [String: Any] = [
  "stringExample": "Hello world!",
  "booleanExample": true,
  "numberExample": 3.14159265,
  "dateExample": Timestamp(date: Date()),
  "arrayExample": [5, true, "hello"],
  "nullExample": NSNull(),
  "objectExample": [
    "a": 5,
    "b": [
      "nested": "foo"
    ]
  ]
]
do {
  try await db.collection("data").document("one").setData(docData)
  print("Document successfully written!")
} catch {
  print("Error writing document: \(error)")
}
ViewController.swift

Objective-C

Note: This product is not available on watchOS and App Clip targets.

NSDictionary *docData = @{
  @"stringExample": @"Hello world!",
  @"booleanExample": @YES,
  @"numberExample": @3.14,
  @"dateExample": [FIRTimestamp timestampWithDate:[NSDate date]],
  @"arrayExample": @[@5, @YES, @"hello"],
  @"nullExample": [NSNull null],
  @"objectExample": @{
    @"a": @5,
    @"b": @{
      @"nested": @"foo"
    }
  }
};

[[[self.db collectionWithPath:@"data"] documentWithPath:@"one"] setData:docData
    completion:^(NSError * _Nullable error) {
      if (error != nil) {
        NSLog(@"Error writing document: %@", error);
      } else {
        NSLog(@"Document successfully written!");
      }
    }];
ViewController.m

Kotlin+KTX

val docData = hashMapOf(
    "stringExample" to "Hello world!",
    "booleanExample" to true,
    "numberExample" to 3.14159265,
    "dateExample" to Timestamp(Date()),
    "listExample" to arrayListOf(1, 2, 3),
    "nullExample" to null,
)

val nestedData = hashMapOf(
    "a" to 5,
    "b" to true,
)

docData["objectExample"] = nestedData

db.collection("data").document("one")
    .set(docData)
    .addOnSuccessListener { Log.d(TAG, "DocumentSnapshot successfully written!") }
    .addOnFailureListener { e -> Log.w(TAG, "Error writing document", e) }
DocSnippets.kt

Java

Map<String, Object> docData = new HashMap<>();
docData.put("stringExample", "Hello world!");
docData.put("booleanExample", true);
docData.put("numberExample", 3.14159265);
docData.put("dateExample", new Timestamp(new Date()));
docData.put("listExample", Arrays.asList(1, 2, 3));
docData.put("nullExample", null);

Map<String, Object> nestedData = new HashMap<>();
nestedData.put("a", 5);
nestedData.put("b", true);

docData.put("objectExample", nestedData);

db.collection("data").document("one")
        .set(docData)
        .addOnSuccessListener(new OnSuccessListener<Void>() {
            @Override
            public void onSuccess(Void aVoid) {
                Log.d(TAG, "DocumentSnapshot successfully written!");
            }
        })
        .addOnFailureListener(new OnFailureListener() {
            @Override
            public void onFailure(@NonNull Exception e) {
                Log.w(TAG, "Error writing document", e);
            }
        });
DocSnippets.java

Dart

final docData = {
  "stringExample": "Hello world!",
  "booleanExample": true,
  "numberExample": 3.14159265,
  "dateExample": Timestamp.now(),
  "listExample": [1, 2, 3],
  "nullExample": null
};

final nestedData = {
  "a": 5,
  "b": true,
};

docData["objectExample"] = nestedData;

db
    .collection("data")
    .doc("one")
    .set(docData)
    .onError((e, _) => print("Error writing document: $e"));
firestore.dart

Java

Map<String, Object> docData = new HashMap<>();
docData.put("stringExample", "Hello, World");
docData.put("booleanExample", false);
docData.put("numberExample", 3.14159265);
docData.put("nullExample", null);

ArrayList<Object> arrayExample = new ArrayList<>();
Collections.addAll(arrayExample, 5L, true, "hello");
docData.put("arrayExample", arrayExample);

Map<String, Object> objectExample = new HashMap<>();
objectExample.put("a", 5L);
objectExample.put("b", true);

docData.put("objectExample", objectExample);

ApiFuture<WriteResult> future = db.collection("data").document("one").set(docData);
System.out.println("Update time : " + future.get().getUpdateTime());
ManageDataSnippets.java

Python

data = {
    "stringExample": "Hello, World!",
    "booleanExample": True,
    "numberExample": 3.14159265,
    "dateExample": datetime.datetime.now(tz=datetime.timezone.utc),
    "arrayExample": [5, True, "hello"],
    "nullExample": None,
    "objectExample": {"a": 5, "b": True},
}

db.collection("data").document("one").set(data)
snippets.py

Python

data = {
    "stringExample": "Hello, World!",
    "booleanExample": True,
    "numberExample": 3.14159265,
    "dateExample": datetime.datetime.now(tz=datetime.timezone.utc),
    "arrayExample": [5, True, "hello"],
    "nullExample": None,
    "objectExample": {"a": 5, "b": True},
}

await db.collection("data").document("one").set(data)
snippets.py

C++

MapFieldValue doc_data{
    {"stringExample", FieldValue::String("Hello world!")},
    {"booleanExample", FieldValue::Boolean(true)},
    {"numberExample", FieldValue::Double(3.14159265)},
    {"dateExample", FieldValue::Timestamp(Timestamp::Now())},
    {"arrayExample", FieldValue::Array({FieldValue::Integer(1),
                                        FieldValue::Integer(2),
                                        FieldValue::Integer(3)})},
    {"nullExample", FieldValue::Null()},
    {"objectExample",
     FieldValue::Map(
         {{"a", FieldValue::Integer(5)},
          {"b", FieldValue::Map(
                    {{"nested", FieldValue::String("foo")}})}})},
};

db->Collection("data").Document("one").Set(doc_data).OnCompletion(
    [](const Future<void>& future) {
      if (future.error() == Error::kErrorOk) {
        std::cout << "DocumentSnapshot successfully written!" << std::endl;
      } else {
        std::cout << "Error writing document: " << future.error_message()
                  << std::endl;
      }
    });
snippets.cpp

Node.js

const data = {
  stringExample: 'Hello, World!',
  booleanExample: true,
  numberExample: 3.14159265,
  dateExample: Timestamp.fromDate(new Date('December 10, 1815')),
  arrayExample: [5, true, 'hello'],
  nullExample: null,
  objectExample: {
    a: 5,
    b: true
  }
};

const res = await db.collection('data').doc('one').set(data);
index.js

Go

import (
	"context"
	"log"
	"time"

	"cloud.google.com/go/firestore"
)

func addDocDataTypes(ctx context.Context, client *firestore.Client) error {
	doc := make(map[string]interface{})
	doc["stringExample"] = "Hello world!"
	doc["booleanExample"] = true
	doc["numberExample"] = 3.14159265
	doc["dateExample"] = time.Now()
	doc["arrayExample"] = []interface{}{5, true, "hello"}
	doc["nullExample"] = nil
	doc["objectExample"] = map[string]interface{}{
		"a": 5,
		"b": true,
	}

	_, err := client.Collection("data").Doc("one").Set(ctx, doc)
	if err != nil {
		// Handle any errors in an appropriate way, such as returning them.
		log.Printf("An error has occurred: %s", err)
	}

	return err
}
save_data_set_from_map_nested.go

PHP

PHP

For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.

$data = [
    'stringExample' => 'Hello World',
    'booleanExample' => true,
    'numberExample' => 3.14159265,
    'dateExample' => new Timestamp(new DateTime()),
    'arrayExample' => array(5, true, 'hello'),
    'nullExample' => null,
    'objectExample' => ['a' => 5, 'b' => true],
    'documentReferenceExample' => $db->collection('samples/php/data')->document('two'),
];
$db->collection('samples/php/data')->document('one')->set($data);
printf('Set multiple data-type data for the one document in the data collection.' . PHP_EOL);
data_set_from_map_nested.php

Unity

DocumentReference docRef = db.Collection("data").Document("one");
Dictionary<string, object> docData = new Dictionary<string, object>
{
	{ "stringExample", "Hello World" },
	{ "booleanExample", false },
	{ "numberExample", 3.14159265 },
	{ "nullExample", null },
	{ "arrayExample", new List<object>() { 5, true, "Hello" } },
	{ "objectExample", new Dictionary<string, object>
		{
			{ "a", 5 },
			{ "b", true },
		}
	},
};

docRef.SetAsync(docData);

C#

DocumentReference docRef = db.Collection("data").Document("one");
Dictionary<string, object> docData = new Dictionary<string, object>
{
    { "stringExample", "Hello World" },
    { "booleanExample", false },
    { "numberExample", 3.14159265 },
    { "nullExample", null },
    { "arrayExample", new object[] { 5, true, "Hello" } },
    { "objectExample", new Dictionary<string, object>
        {
            { "a", 5 },
            { "b", true},
        }
    }
};

await docRef.SetAsync(docData);
Program.cs

Ruby

doc_ref = firestore.doc "#{collection_path}/one"

data = {
  stringExample:  "Hello, World!",
  booleanExample: true,
  numberExample:  3.14159265,
  dateExample:    DateTime.now,
  arrayExample:   [5, true, "hello"],
  nullExample:    nil,
  objectExample:  {
    a: 5,
    b: true
  }
}

doc_ref.set data
add_data.rb

Custom objects

Using Map or Dictionary objects to represent your documents is often inconvenient, so Cloud Firestore supports writing documents with custom classes. Cloud Firestore converts the objects to supported data types.

Using custom classes, you can rewrite the initial example in the following way:

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

class City {
    constructor (name, state, country ) {
        this.name = name;
        this.state = state;
        this.country = country;
    }
    toString() {
        return this.name + ', ' + this.state + ', ' + this.country;
    }
}

// Firestore data converter
const cityConverter = {
    toFirestore: (city) => {
        return {
            name: city.name,
            state: city.state,
            country: city.country
            };
    },
    fromFirestore: (snapshot, options) => {
        const data = snapshot.data(options);
        return new City(data.name, data.state, data.country);
    }
};
city_custom_object.js

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

class City {
    constructor (name, state, country ) {
        this.name = name;
        this.state = state;
        this.country = country;
    }
    toString() {
        return this.name + ', ' + this.state + ', ' + this.country;
    }
}

// Firestore data converter
var cityConverter = {
    toFirestore: function(city) {
        return {
            name: city.name,
            state: city.state,
            country: city.country
            };
    },
    fromFirestore: function(snapshot, options){
        const data = snapshot.data(options);
        return new City(data.name, data.state, data.country);
    }
};
test.firestore.js

Swift

Note: This product is not available on watchOS and App Clip targets.

public struct City: Codable {

  let name: String
  let state: String?
  let country: String?
  let isCapital: Bool?
  let population: Int64?

  enum CodingKeys: String, CodingKey {
    case name
    case state
    case country
    case isCapital = "capital"
    case population
  }

}
ViewController.swift

Objective-C

Note: This product is not available on watchOS and App Clip targets.

// This isn't supported in Objective-C.
  

Kotlin+KTX

data class City(
    val name: String? = null,
    val state: String? = null,
    val country: String? = null,
    @field:JvmField // use this annotation if your Boolean field is prefixed with 'is'
    val isCapital: Boolean? = null,
    val population: Long? = null,
    val regions: List<String>? = null,
)
DocSnippets.kt

Java

Each custom class must have a public constructor that takes no arguments. In addition, the class must include a public getter for each property.

public class City {


    private String name;
    private String state;
    private String country;
    private boolean capital;
    private long population;
    private List<String> regions;

    public City() {}

    public City(String name, String state, String country, boolean capital, long population, List<String> regions) {
        // ...
    }

    public String getName() {
        return name;
    }

    public String getState() {
        return state;
    }

    public String getCountry() {
        return country;
    }

    public boolean isCapital() {
        return capital;
    }

    public long getPopulation() {
        return population;
    }

    public List<String> getRegions() {
        return regions;
    }

}
DocSnippets.java

Dart

class City {
  final String? name;
  final String? state;
  final String? country;
  final bool? capital;
  final int? population;
  final List<String>? regions;

  City({
    this.name,
    this.state,
    this.country,
    this.capital,
    this.population,
    this.regions,
  });

  factory City.fromFirestore(
    DocumentSnapshot<Map<String, dynamic>> snapshot,
    SnapshotOptions? options,
  ) {
    final data = snapshot.data();
    return City(
      name: data?['name'],
      state: data?['state'],
      country: data?['country'],
      capital: data?['capital'],
      population: data?['population'],
      regions:
          data?['regions'] is Iterable ? List.from(data?['regions']) : null,
    );
  }

  Map<String, dynamic> toFirestore() {
    return {
      if (name != null) "name": name,
      if (state != null) "state": state,
      if (country != null) "country": country,
      if (capital != null) "capital": capital,
      if (population != null) "population": population,
      if (regions != null) "regions": regions,
    };
  }
}
firestore_add_data_custom_objects_snippet.dart

Java

public City() {
  // Must have a public no-argument constructor
}

// Initialize all fields of a city
public City(
    String name,
    String state,
    String country,
    Boolean capital,
    Long population,
    List<String> regions) {
  this.name = name;
  this.state = state;
  this.country = country;
  this.capital = capital;
  this.population = population;
  this.regions = regions;
}
City.java

Python

class City:
    def __init__(self, name, state, country, capital=False, population=0, regions=[]):
        self.name = name
        self.state = state
        self.country = country
        self.capital = capital
        self.population = population
        self.regions = regions

    @staticmethod
    def from_dict(source):
        # ...

    def to_dict(self):
        # ...

    def __repr__(self):
        return f"City(\
                name={self.name}, \
                country={self.country}, \
                population={self.population}, \
                capital={self.capital}, \
                regions={self.regions}\
            )"

snippets.py

Python

class City:
    def __init__(self, name, state, country, capital=False, population=0, regions=[]):
        self.name = name
        self.state = state
        self.country = country
        self.capital = capital
        self.population = population
        self.regions = regions

    @staticmethod
    def from_dict(source):
        # ...

    def to_dict(self):
        # ...

    def __repr__(self):
        return f"City(\
                name={self.name}, \
                country={self.country}, \
                population={self.population}, \
                capital={self.capital}, \
                regions={self.regions}\
            )"

snippets.py

C++

// This is not yet supported.

Node.js

// Node.js uses JavaScript objects

Go

// City represents a city.
type City struct {
	Name       string   `firestore:"name,omitempty"`
	State      string   `firestore:"state,omitempty"`
	Country    string   `firestore:"country,omitempty"`
	Capital    bool     `firestore:"capital,omitempty"`
	Population int64    `firestore:"population,omitempty"`
	Density    int64    `firestore:"density,omitempty"`
	Regions    []string `firestore:"regions,omitempty"`
}
custom_type_definition.go

PHP

PHP

For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.

class City
{
    /** @var string */
    public $name;
    /** @var string */
    public $state;
    /** @var string */
    public $country;
    /** @var bool */
    public $capital;
    /** @var int */
    public $population;
    /** @var array<string> */
    public $regions;

    /**
     * @param array<string> $regions
     */
    public function __construct(
        string $name,
        string $state,
        string $country,
        bool $capital = false,
        int $population = 0,
        array $regions = []
    ) {
        $this->name = $name;
        $this->state = $state;
        $this->country = $country;
        $this->capital = $capital;
        $this->population = $population;
        $this->regions = $regions;
    }

    /**
     * @param array<mixed> $source
     */
    public static function fromArray(array $source): City
    {
        // implementation of fromArray is excluded for brevity
        # ...
    }

    /**
     * @return array<mixed>
     */
    public function toArray(): array
    {
        // implementation of toArray is excluded for brevity
        # ...
    }

    public function __toString()
    {
        // implementation of __toString is excluded for brevity
        # ...
    }
}
City.php

Unity

[FirestoreData]
public class City
{
	[FirestoreProperty]
	public string Name { get; set; }

	[FirestoreProperty]
	public string State { get; set; }

	[FirestoreProperty]
	public string Country { get; set; }

	[FirestoreProperty]
	public bool Capital { get; set; }

	[FirestoreProperty]
	public long Population { get; set; }
}

C#

[FirestoreData]
public class City
{
    [FirestoreProperty]
    public string Name { get; set; }

    [FirestoreProperty]
    public string State { get; set; }

    [FirestoreProperty]
    public string Country { get; set; }

    [FirestoreProperty]
    public bool Capital { get; set; }

    [FirestoreProperty]
    public long Population { get; set; }
}
Program.cs

Ruby

// This isn't supported in Ruby

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

import { doc, setDoc } from "firebase/firestore"; 

// Set with cityConverter
const ref = doc(db, "cities", "LA").withConverter(cityConverter);
await setDoc(ref, new City("Los Angeles", "CA", "USA"));
set_custom_object.js

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

// Set with cityConverter
db.collection("cities").doc("LA")
  .withConverter(cityConverter)
  .set(new City("Los Angeles", "CA", "USA"));
test.firestore.js

Swift

Note: This product is not available on watchOS and App Clip targets.

let city = City(name: "Los Angeles",
                state: "CA",
                country: "USA",
                isCapital: false,
                population: 5000000)

do {
  try db.collection("cities").document("LA").setData(from: city)
} catch let error {
  print("Error writing city to Firestore: \(error)")
}
ViewController.swift

Objective-C

Note: This product is not available on watchOS and App Clip targets.

// This isn't supported in Objective-C.
  

Kotlin+KTX

val city = City(
    "Los Angeles",
    "CA",
    "USA",
    false,
    5000000L,
    listOf("west_coast", "socal"),
)
db.collection("cities").document("LA").set(city)
DocSnippets.kt

Java

City city = new City("Los Angeles", "CA", "USA",
        false, 5000000L, Arrays.asList("west_coast", "sorcal"));
db.collection("cities").document("LA").set(city);
DocSnippets.java

Dart

final city = City(
  name: "Los Angeles",
  state: "CA",
  country: "USA",
  capital: false,
  population: 5000000,
  regions: ["west_coast", "socal"],
);
final docRef = db
    .collection("cities")
    .withConverter(
      fromFirestore: City.fromFirestore,
      toFirestore: (City city, options) => city.toFirestore(),
    )
    .doc("LA");
await docRef.set(city);
firestore.dart

Java

City city =
    new City("Los Angeles", "CA", "USA", false, 3900000L, Arrays.asList("west_coast", "socal"));
ApiFuture<WriteResult> future = db.collection("cities").document("LA").set(city);
// block on response if required
System.out.println("Update time : " + future.get().getUpdateTime());
ManageDataSnippets.java

Python

city = City(name="Los Angeles", state="CA", country="USA")
db.collection("cities").document("LA").set(city.to_dict())
snippets.py

Python

city = City(name="Los Angeles", state="CA", country="USA")
await db.collection("cities").document("LA").set(city.to_dict())
snippets.py

C++

// This is not yet supported.

Node.js

// Node.js uses JavaScript objects

Go

import (
	"context"
	"log"

	"cloud.google.com/go/firestore"
)

func addDocAsEntity(ctx context.Context, client *firestore.Client) error {
	city := City{
		Name:    "Los Angeles",
		Country: "USA",
	}
	_, err := client.Collection("cities").Doc("LA").Set(ctx, city)
	if err != nil {
		// Handle any errors in an appropriate way, such as returning them.
		log.Printf("An error has occurred: %s", err)
	}

	return err
}
save_data_set_from_custom_type.go

PHP

// This isn't supported in PHP.

Unity

DocumentReference docRef = db.Collection("cities").Document("LA");
City city = new City
{
	Name = "Los Angeles",
	State = "CA",
	Country = "USA",
	Capital = false,
	Population = 3900000L
};
docRef.SetAsync(city);

C#

DocumentReference docRef = db.Collection("cities").Document("LA");
City city = new City
{
    Name = "Los Angeles",
    State = "CA",
    Country = "USA",
    Capital = false,
    Population = 3900000L
};
await docRef.SetAsync(city);
Program.cs

Ruby

// This isn't supported in Ruby.

Add a document

When you use set() to create a document, you must specify an ID for the document to create, as shown in the following example:

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

import { doc, setDoc } from "firebase/firestore"; 

await setDoc(doc(db, "cities", "new-city-id"), data);
cities_document_set.js

Web

Learn more about the tree-shakeable modular Web API and upgrade from the namespaced API.

db.collection("cities").doc("new-city-id").set(data);
test.firestore.js

Swift

Note: This product is not available on watchOS and App Clip targets.

db.collection("cities").document("new-city-id").setData(data)
ViewController.swift

Objective-C

Note: This product is not available on watchOS and App Clip targets.

[[[self.db collectionWithPath:@"cities"] documentWithPath:@"new-city-id"]
    setData:data];
ViewController.m

Kotlin+KTX

db.collection("cities").document("new-city-id").set(data)
DocSnippets.kt

Java

db.collection("cities").document("new-city-id").set(data);
DocSnippets.java

Dart

db.collection("cities").doc("new-city-id").set({"name": "Chicago"});
firestore.dart

Java

db.collection("cities").document("new-city-id").set(data);
ManageDataSnippets.java

Python

db.collection("cities").document("new-city-id").set(data)
snippets.py

Python

await db.collection("cities").document("new-city-id").set(data)
snippets.py

C++

db->Collection("cities").Document("SF").Set({/*some data*/});
snippets.cpp

Node.js

await db.collection('cities').doc('new-city-id').set(data);
index.js

Go

import (
	"context"
	"log"

	"cloud.google.com/go/firestore"
)

func addDocWithID(ctx context.Context, client *firestore.Client) error {
	var data = make(map[string]interface{})

	_, err := client.Collection("cities").Doc("new-city-id").Set(ctx, data)
	if err != nil {
		// Handle any errors in an appropriate way, such as returning them.
		log.Printf("An error has occurred: %s", err)
	}

	return err
}
save_data_set_id_specified.go

PHP

PHP

For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.

$db->collection('samples/php/cities')->document('new-city-id')->set($data);
data_set_id_specified.php

Unity

db.Collection("cities").Document("new-city-id").SetAsync(city);

C#

await db.Collection("cities").Document("new-city-id").SetAsync(city);
Program.cs

Ruby

city_ref = firestore.doc "#{collection_path}/new-city-id"
city_ref.set data
add_data.rb

If there isn't a meaningful ID for the document, Cloud Firestore can auto-generate an ID for you. You can call the following language-specific add() methods:

Web

Use the addDoc() method:

import { collection, addDoc } from "firebase/firestore"; 

// Add a new document with a generated id.
const docRef = await addDoc(collection(db, "cities"), {
  name: "Tokyo",
  country: "Japan"
});
console.log("Document written with ID: ", docRef.id);
add_document.js

Web

Use the add() method:

// Add a new document with a generated id.
db.collection("cities").add({
    name: "Tokyo",
    country: "Japan"
})
.then((docRef) => {
    console.log("Document written with ID: ", docRef.id);
})
.catch((error) => {
    console.error("Error adding document: ", error);
});
test.firestore.js

Swift

Use the addDocument() method:

Note: This product is not available on watchOS and App Clip targets.

// Add a new document with a generated id.
do {
  let ref = try await db.collection("cities").addDocument(data: [
    "name": "Tokyo",
    "country": "Japan"
  ])
  print("Document added with ID: \(ref.documentID)")
} catch {
  print("Error adding document: \(error)")
}
ViewController.swift

Objective-C

Use the addDocumentWithData: method:

Note: This product is not available on watchOS and App Clip targets.

// Add a new document with a generated id.
__block FIRDocumentReference *ref =
    [[self.db collectionWithPath:@"cities"] addDocumentWithData:@{
      @"name": @"Tokyo",
      @"country": @"Japan"
    } completion:^(NSError * _Nullable error) {
      if (error != nil) {
        NSLog(@"Error adding document: %@", error);
      } else {
        NSLog(@"Document added with ID: %@", ref.documentID);
      }
    }];
ViewController.m

Kotlin+KTX

Use the add() method:

// Add a new document with a generated id.
val data = hashMapOf(
    "name" to "Tokyo",
    "country" to "Japan",
)

db.collection("cities")
    .add(data)
    .addOnSuccessListener { documentReference ->
        Log.d(TAG, "DocumentSnapshot written with ID: ${documentReference.id}")
    }
    .addOnFailureListener { e ->
        Log.w(TAG, "Error adding document", e)
    }
DocSnippets.kt

Java

Use the add() method:

// Add a new document with a generated id.
Map<String, Object> data = new HashMap<>();
data.put("name", "Tokyo");
data.put("country", "Japan");

db.collection("cities")
        .add(data)
        .addOnSuccessListener(new OnSuccessListener<DocumentReference>() {
            @Override
            public