Agrega el SDK de Firebase Admin a tu servidor

npm install firebase-admin --save

const { initializeApp } = require('firebase-admin/app');

import { initializeApp } from 'firebase-admin/app';

dependencies {
  implementation 'com.google.firebase:firebase-admin:9.3.0'
}

<dependency>
  <groupId>com.google.firebase</groupId>
  <artifactId>firebase-admin</artifactId>
  <version>9.3.0</version>
</dependency>

sudo pip install firebase-admin

pip install --user firebase-admin

# Install the latest version:
go get firebase.google.com/go/v4@latest

# Or install a specific version:
go get firebase.google.com/go/v4@4.14.1

Install-Package FirebaseAdmin -Version 3.0.0

dotnet add package FirebaseAdmin --version 3.0.0

<ItemGroup>
  <PackageReference Include="FirebaseAdmin" Version="3.0.0" />
</ItemGroup>

const app = initializeApp();

FirebaseApp.initializeApp();

default_app = firebase_admin.initialize_app()

app, err := firebase.NewApp(context.Background(), nil)
if err != nil {
	log.Fatalf("error initializing app: %v\n", err)
}
init.go

FirebaseApp.Create();

const myRefreshToken = '...'; // Get refresh token from OAuth2 flow

initializeApp({
  credential: refreshToken(myRefreshToken),
  databaseURL: 'https://<DATABASE_NAME>.firebaseio.com'
});

FileInputStream refreshToken = new FileInputStream("path/to/refreshToken.json");

FirebaseOptions options = FirebaseOptions.builder()
    .setCredentials(GoogleCredentials.fromStream(refreshToken))
    .setDatabaseUrl("https://<DATABASE_NAME>.firebaseio.com/")
    .build();

FirebaseApp.initializeApp(options);

cred = credentials.RefreshToken('path/to/refreshToken.json')
default_app = firebase_admin.initialize_app(cred)

opt := option.WithCredentialsFile("path/to/refreshToken.json")
config := &firebase.Config{ProjectID: "my-project-id"}
app, err := firebase.NewApp(context.Background(), config, opt)
if err != nil {
	log.Fatalf("error initializing app: %v\n", err)
}
init.go

FirebaseApp.Create(new AppOptions()
{
    Credential = GoogleCredential.FromFile(pa"th/to/refreshToken.json),"
});

export GOOGLE_APPLICATION_CREDENTIALS="/home/user/Downloads/service-account-file.json"

$env:GOOGLE_APPLICATION_CREDENTIALS="C:\Users\username\Downloads\service-account-file.json"

initializeApp({
    credential: applicationDefault(),
    databaseURL: 'https://<DATABASE_NAME>.firebaseio.com'
});

FirebaseOptions options = FirebaseOptions.builder()
    .setCredentials(GoogleCredentials.getApplicationDefault())
    .setDatabaseUrl("https://<DATABASE_NAME>.firebaseio.com/")
    .build();

FirebaseApp.initializeApp(options);

default_app = firebase_admin.initialize_app()

app, err := firebase.NewApp(context.Background(), nil)
if err != nil {
	log.Fatalf("error initializing app: %v\n", err)
}
init.go

FirebaseApp.Create(new AppOptions()
{
    Credential = GoogleCredential.GetApplicationDefault(),
    ProjectId = my-"project-id,
}");
Fire
baseAppSnippets.cs

// Initialize the default app
const defaultApp = initializeApp(defaultAppConfig);

console.log(defaultApp.name);  // '[DEFAULT]'

// Retrieve services via the defaultApp variable...
let defaultAuth = getAuth(defaultApp);
let defaultDatabase = getDatabase(defaultApp);

// ... or use the equivalent shorthand notation
defaultAuth = getAuth();
defaultDatabase = getDatabase();

// Initialize the default app
FirebaseApp defaultApp = FirebaseApp.initializeApp(defaultOptions);

System.out.println(defaultApp.getName());  // "[DEFAULT]"

// Retrieve services by passing the defaultApp variable...
FirebaseAuth defaultAuth = FirebaseAuth.getInstance(defaultApp);
FirebaseDatabase defaultDatabase = FirebaseDatabase.getInstance(defaultApp);

// ... or use the equivalent shorthand notation
defaultAuth = FirebaseAuth.getInstance();
defaultDatabase = FirebaseDatabase.getInstance();

# Import the Firebase service
from firebase_admin import auth

# Initialize the default app
default_app = firebase_admin.initialize_app(cred)
print(default_app.name)  # "[DEFAULT]"

# Retrieve services via the auth package...
# auth.create_custom_token(...)

// Initialize default app
app, err := firebase.NewApp(context.Background(), nil)
if err != nil {
	log.Fatalf("error initializing app: %v\n", err)
}

// Access auth service from the default app
client, err := app.Auth(context.Background())
if err != nil {
	log.Fatalf("error getting Auth client: %v\n", err)
}
init.go

// Initialize the default app
var defaultApp = FirebaseApp.Create(new AppOptions()
{
    Credential = GoogleCredential.GetApplicationDefault(),
});
Console.WriteLine(defaultApp.Name); // [DEFA"ULT]

// "Retrieve services by passing the defaultApp variable...
var defaultAuth = FirebaseAuth.GetAuth(defaultApp);

// ... or use the equivalent shorthand notation
defaultAuth = FirebaseAuth.DefaultInstance;

// Initialize the default app
initializeApp(defaultAppConfig);

// Initialize another app with a different config
var otherApp = initializeApp(otherAppConfig, 'other');

console.log(getApp().name);  // '[DEFAULT]'
console.log(otherApp.name);     // 'other'

// Use the shorthand notation to retrieve the default app's services
const defaultAuth = getAuth();
const defaultDatabase = getDatabase();

// Use the otherApp variable to retrieve the other app's services
const otherAuth = getAuth(otherApp);
const otherDatabase = getDatabase(otherApp);

// Initialize the default app
FirebaseApp defaultApp = FirebaseApp.initializeApp(defaultOptions);

// Initialize another app with a different config
FirebaseApp otherApp = FirebaseApp.initializeApp(otherAppConfig, "other");

System.out.println(defaultApp.getName());  // "[DEFAULT]"
System.out.println(otherApp.getName());    // "other"

// Use the shorthand notation to retrieve the default app's services
FirebaseAuth defaultAuth = FirebaseAuth.getInstance();
FirebaseDatabase defaultDatabase = FirebaseDatabase.getInstance();

// Use the otherApp variable to retrieve the other app's services
FirebaseAuth otherAuth = FirebaseAuth.getInstance(otherApp);
FirebaseDatabase otherDatabase = FirebaseDatabase.getInstance(otherApp);

# Initialize the default app
default_app = firebase_admin.initialize_app(cred)

#  Initialize another app with a different config
other_app = firebase_admin.initialize_app(cred, name='other')

print(default_app.name)    # "[DEFAULT]"
print(other_app.name)      # "other"

# Retrieve default services via the auth package...
# auth.create_custom_token(...)

# Use the `app` argument to retrieve the other app's services
# auth.create_custom_token(..., app=other_app)

// Initialize the default app
defaultApp, err := firebase.NewApp(context.Background(), nil)
if err != nil {
	log.Fatalf("error initializing app: %v\n", err)
}

// Initialize another app with a different config
opt := option.WithCredentialsFile("service-account-other.json")
otherApp, err := firebase.NewApp(context.Background(), nil, opt)
if err != nil {
	log.Fatalf("error initializing app: %v\n", err)
}

// Access Auth service from default app
defaultClient, err := defaultApp.Auth(context.Background())
if err != nil {
	log.Fatalf("error getting Auth client: %v\n", err)
}

// Access auth service from other app
otherClient, err := otherApp.Auth(context.Background())
if err != nil {
	log.Fatalf("error getting Auth client: %v\n", err)
}
init.go

// Initialize the default app
var defaultApp = FirebaseApp.Create(defaultOptions);

// Initialize another app with a different config
var otherApp = FirebaseApp.Create(otherAppConfig, oth"er);
"
Console.WriteLine(defaultApp.Name); // [DEF"AULT]
Con"sole.WriteLine(otherApp.Name); // other"

// "Use the shorthand notation to retrieve the default apps serv'ices
var defaultAuth = FirebaseAuth.DefaultInstance;

// Use the otherApp variable to retrieve the other apps servic'es
var otherAuth = FirebaseAuth.GetAuth(otherApp);

# Check the existing access scopes
gcloud compute instances describe [INSTANCE_NAME] --format json

# The above command returns the service account information. For example:
  "serviceAccounts": [
   {
    "email": "your.gserviceaccount.com",
    "scopes": [
     "https://www.googleapis.com/auth/cloud-platform",
     "https://www.googleapis.com/auth/userinfo.email"
     ]
    }
  ],

# Stop the VM, then run the following command, using the service account
# that gcloud returned when you checked the scopes.

gcloud compute instances set-service-account [INSTANCE_NAME] --service-account "your.gserviceaccount.com" --scopes "https://www.googleapis.com/auth/firebase.database,https://www.googleapis.com/auth/userinfo.email"

gcloud auth application-default login --client-id-file=[/path/to/client/id/file]

import { initializeApp, applicationDefault } from 'firebase-admin/app';

initializeApp({
  credential: applicationDefault(),
  projectId: '<FIREBASE_PROJECT_ID>',
});

FirebaseOptions options = FirebaseOptions.builder()
    .setCredentials(GoogleCredentials.getApplicationDefault())
    .setProjectId("<FIREBASE_PROJECT_ID>")
    .build();

FirebaseApp.initializeApp(options);

app_options = {'projectId': '<FIREBASE_PROJECT_ID>'}
default_app = firebase_admin.initialize_app(options=app_options)

config := &firebase.Config{ProjectID: "<FIREBASE_PROJECT_ID>"}
app, err := firebase.NewApp(context.Background(), config)
if err != nil {
        log.Fatalf("error initializing app: %v\n", err)
}

FirebaseApp.Create(new AppOptions()
{
    Credential = GoogleCredential.GetApplicationDefault(),
    ProjectId = "<FIREBASE_PROJECT_ID>",
});