Solve Null InjectorError: No Provider For AngularFirestore - Definitive Guide

The AngularFirestore service is a service that provides access to the Firebase Firestore database. It is a powerful tool that can be used to store and retrieve data in real-time.

The NullInjectorError: No provider for AngularFirestore error can be caused by a few things:

The AngularFirestore library is not installed correctly.

The AngularFirestore service is not imported in the Angular module.
The AngularFirestore service is not added to the providers array of the Angular module.

In this article, we will discuss the cause of the NullInjectorError: No provider for AngularFirestore error and how to fix it. We will also provide some additional tips on how to avoid this error in the future.

Quick Answer: Add AngularFirestoreModule in the imports and AngularFirestore in the providers array of the App.module.ts file.

 imports: [

    AngularFireModule.initializeApp(environment.firebaseConfig), // Initialize AngularFire with your Firebase configuration

    AngularFirestoreModule, // Import and configure AngularFirestoreModule

  ],

providers: [AngularFirestore],

Table of Contents

App.module.ts File Overview

The app.module.ts is the main module file in an Angular application. It is responsible for bootstrapping the application and declaring the components, directives, and pipes that are used in the application.

The AppModule file is typically located in the src/app folder of the Angular application. It must export a class that extends the NgModule class. The NgModule class has the following properties:

declarations: an array of the components, directives, and pipes that are used in the application.
imports: an array of the modules that are imported by the application.
providers: an array of the services that are provided by the application.

bootstrap: an array of the components that are used to bootstrap the application.

The following is an example of an AppModule file:

import { NgModule } from '@angular/core';

import { AppComponent } from './app.component';

@NgModule({

  declarations: [AppComponent],

  imports: [],

  providers: [],

  bootstrap: [AppComponent]

})

export class AppModule {}

In this example, the AppModule file declares the AppComponent, which is the application’s root component. The AppModule file also imports the NgModule class from the @angular/core library.

Installing AngularFirestore Libraries

To use the firestore in your application, you need to Install the AngularFirestore library.

You can do this by running the following command in the terminal:

npm install @angular/fire firebase

Step 1 – Importing AngularFirestore

Import the AngularFirestore service in the Angular module.

You can do this by adding the following import statement to the Angular module:

import { AngularFirestore } from '@angular/fire/firestore';

Step 2 – Adding AngularFirestore in Import Statement

 imports: [

    BrowserModule,

    .....
    AngularFireModule.initializeApp(firebaseConfig),

    AngularFirestoreModule

  ],

In the imports array of the AppModule class, you need to import the following modules:

BrowserModule: This module is required for all Angular applications that run in the browser.
AngularFireModule.initializeApp(firebaseConfig): This module initializes the Firebase SDK with our Firebase project configuration

AngularFirestoreModule: This module imports the AngularFirestore library. The AngularFirestoreModule module must be imported after the AngularFireModule.initializeApp(firebaseConfig) module. This is because the AngularFirestoreModule module depends on the AngularFireModule module

Step 3 – Adding AngularFirestore in Providers

Add the AngularFirestore service to the providers array of the Angular module. You can do this by adding the following line to the providers array:

providers: [AngularFirestore],

Make sure that you are using the latest version of the AngularFirestore library.

App.module.ts File with AngularFireStore

The app.module.ts file with the AngularFireStore would be like the one below:

import { NgModule } from '@angular/core';

import { BrowserModule } from '@angular/platform-browser';


import { AngularFireModule } from '@angular/fire';

import { AngularFirestoreModule } from '@angular/fire/firestore'; // Import AngularFirestoreModule

import { environment } from 'src/environments/environment'; // Import your Firebase configuration from environment

import { AppComponent } from './app.component';

@NgModule({

  declarations: [AppComponent],

  imports: [

    BrowserModule,

    AngularFireModule.initializeApp(environment.firebaseConfig), // Initialize AngularFire with your Firebase configuration

    AngularFirestoreModule, // Import and configure AngularFirestoreModule

  ],

  providers: [AngularFirestore],


  bootstrap: [AppComponent],

})

export class AppModule {}

Troubleshooting Tips

Import order: The order in which you import modules can matter. Make sure that the AngularFirestore module is imported after the AngularFireModule module.
Package versions: Make sure you use the same versions of the AngularFirestore and AngularFire modules. You can check the AngularFirestore documentation for the latest versions of the modules.

Injection points: Make sure that the AngularFirestore service is injected into the correct place. For example, if you are trying to use the AngularFirestore service in a component, you must inject it into its constructor.
Service name case sensitivity: Make sure that the name of the AngularFirestore service is spelt correctly. The Angular injector is case-sensitive, so if you misspell the name of the service, you will get an error.
Dependencies: Make sure that the AngularFirestore service is not dependent on any other services that are not available. For example, if the AngularFirestore service depends on the FirebaseAuth service, ensure that the FirebaseAuth service is also imported and configured correctly.

Conclusion

In conclusion, the NullInjectorError: No provider for AngularFirestore error is a common error that Angular developers encounter when using the AngularFirestore library. A few things can cause this error, but it is usually due to the AngularFirestore library not being installed correctly or the AngularFirestore service not being imported in the Angular module.

To fix this error, you must ensure the AngularFirestore library is installed correctly, and the AngularFirestore service is imported into the Angular module. You also need to add the AngularFirestore service to the providers array of the Angular module.

Additional Resources

Solve FireBase Google Cloud Firestore: PERMISSION_DENIED: Missing or insufficient permissions Error

Solve Null InjectorError: No provider for AngularFirestore – Definitive Guide