Sending emails using SMTP
This guide demonstrates how your Quarkus application can send emails using an SMTP server. This is a getting started guide. Check the Quarkus Mailer Reference documentation for more complete explanation about the mailer and its usage.
Pré-requisitos
Para concluir este guia, você precisa:
-
Cerca de 15 minutos
-
Um IDE
-
JDK 17+ installed with
JAVA_HOME
configured appropriately -
Apache Maven 3.9.9
-
Opcionalmente, o Quarkus CLI se você quiser usá-lo
-
Opcionalmente, Mandrel ou GraalVM instalado e configurado apropriadamente se você quiser criar um executável nativo (ou Docker se você usar uma compilação de contêiner nativo)
-
The SMTP hostname, port and credentials, and an email address
-
cURL
Arquitetura
In this guide, we will build an application:
-
exposing an HTTP endpoint,
-
sending email when the endpoint receives an HTTP request.
The application will demonstrate how to send emails using the imperative and reactive mailer APIs.
Attachments, inlined attachments, templating, testing and more advanced configuration are covered in the Mailer Reference documentation.
Solução
Recomendamos que siga as instruções nas seções seguintes e crie a aplicação passo a passo. No entanto, você pode ir diretamente para o exemplo completo.
Clone o repositório Git: git clone https://github.com/quarkusio/quarkus-quickstarts.git
, ou baixe um arquivo.
The solution is located in the mailer-quickstart
directory.
Create the Maven Project
Primeiro, precisamos de um novo projeto. Crie um novo projeto com o seguinte comando:
Para usuários do Windows:
-
Se estiver usando cmd, (não use barra invertida '\' e coloque tudo na mesma linha)
-
Se estiver usando o Powershell, envolva os parâmetros '-D' entre aspas duplas, por exemplo, '"-DprojectArtifactId=mailer-quickstart"'
This command generates a Maven structure including the following extensions:
-
Quarkus REST (formerly RESTEasy Reactive) used to expose REST endpoints
-
Mailer so that we can send emails
-
Qute, our template engine
If you already have your Quarkus project configured, you can add the mailer
extension
to your project by running the following command in your project base directory:
quarkus extension add mailer
./mvnw quarkus:add-extension -Dextensions='mailer'
./gradlew addExtension --extensions='mailer'
Isso adicionará o seguinte ao seu arquivo pom.xml
:
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-mailer</artifactId>
</dependency>
implementation("io.quarkus:quarkus-mailer")
Open the generated project in your IDE. In a terminal, navigate to the project and start your application in dev mode:
quarkus dev
./mvnw quarkus:dev
./gradlew --console=plain quarkusDev
Implement the HTTP endpoint
First, create the src/main/java/org/acme/MailResource.java
file, with the following content:
package org.acme;
import io.quarkus.mailer.Mail;
import io.quarkus.mailer.Mailer;
import io.smallrye.common.annotation.Blocking;
import jakarta.inject.Inject;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.Path;
@Path("/mail") (1)
public class MailResource {
@Inject Mailer mailer; (2)
@GET (3)
@Blocking (4)
public void sendEmail() {
mailer.send(
Mail.withText("quarkus@quarkus.io", (5)
"Ahoy from Quarkus",
"A simple email sent from a Quarkus application."
)
);
}
}
1 | Configure the root path of our HTTP endpoint |
2 | Inject the Mailer object managed by Quarkus |
3 | Create a method that will handle the HTTP GET request on /mail |
4 | Because we are using Quarkus REST and the imperative mailer, we need to add the @Blocking annotation. We will see later the reactive variant. |
5 | Create a Mail object by configuring the to recipient, the subject and body |
The MailResource
class implements the HTTP API exposed by our application.
It handles GET
request on `http://localhost:8080/mail.
So, if in another terminal, you run:
> curl http://localhost:8080/mail
You should see in the application log something like:
INFO [quarkus-mailer] (executor-thread-0) Sending email Ahoy from Quarkus from null to [quarkus@quarkus.io], text body:
A simple email sent from a Quarkus application.
html body:
<empty>
As the application runs in dev mode, it simulates the sending of the emails. It prints it in the log, so you can check that what was about to be sent.
This section used the imperative mailer API. It blocks the caller thread until the mail is sent. |
The Quarkus Mailpit extension is very handy for testing emails. It provides Dev Services for Mailpit, a nice UI for testing and debugging email sending. |
Using the reactive mailer
The last section use the imperative mailer. Quarkus also offers a reactive API.
Mutiny
The reactive mailer uses Mutiny reactive types. If you are not familiar with Mutiny, check Mutiny - an intuitive reactive programming library. |
In the same class, add:
@Inject
ReactiveMailer reactiveMailer; (1)
@GET
@Path("/reactive") (2)
public Uni<Void> sendEmailUsingReactiveMailer() { (3)
return reactiveMailer.send( (4)
Mail.withText("quarkus@quarkus.io",
"Ahoy from Quarkus",
"A simple email sent from a Quarkus application using the reactive API."
)
);
}
1 | Inject the reactive mailer. The class to import is io.quarkus.mailer.reactive.ReactiveMailer . |
2 | Configure the path to handle GET request on /mail/reactive . Note that because we are using the reactive API, we don’t need @Blocking |
3 | The method returns a Uni<Void> which completes when the mail is sent. It does not block the caller thread. |
4 | The API is similar to the imperative one except that the send method returns a Uni<Void> . |
Now, in your terminal, run
> curl http://localhost:8080/mail/reactive
You should see in the application log something like:
INFO [quarkus-mailer] (vert.x-eventloop-thread-11) Sending email Ahoy from Quarkus from null to [quarkus@quarkus.io], text body:
A simple email sent from a Quarkus application using the reactive API.
html body:
<empty>
Configuring the mailer
It’s time to configure the mailer to not simulate the sending of the emails. The Quarkus mailer is using SMTP, so make sure you have access to an SMTP server.
In the src/main/resources/application.properties
file, you need to configure the host, port, username, password as well as the other configuration aspect.
Note that the password can also be configured using system properties and environment variables.
See the configuration reference guide for details.
Configuration of popular mail services is covered in the reference guide.
Once you have configured the mailer, if you call the HTTP endpoint as shown above, you will send emails.
Conclusion
This guide has shown how to send emails from your Quarkus application. The mailer reference guide provides more details about the mailer usage and configuration such as: