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 theAngularFireModule.initializeApp(firebaseConfig) module
. This is because theAngularFirestoreModule
module depends on theAngularFireModule
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.