mailer - endpoint invocation stays blocked when having mailer misconfigured

[rsvoboda]

Describe the bug

mailer - endpoint invocation stays blocked when having mailer misconfigured

when I used config based on https://quarkus.io/guides/mailer#configuring-the-mailer and invoked curl localhost:8080/mail/ I got warning and error in log

2022-09-14 09:54:06,624 WARN [io.ver.ext.mai.imp.SMTPAuthentication] (vert.x-eventloop-thread-0) io.vertx.ext.mail.SMTPException: AUTH LOGIN failed: 535 Authentication failed: Bad username / password
2022-09-14 09:54:06,634 ERROR [io.ver.ext.mai.imp.SMTPConnection] (vert.x-eventloop-thread-0) SSLEngine closed already

But curl command didn't finish, still waiting for response.
And I had to interrupt it using Ctrl+C

Endpoint invocation shouldn't be blocked, looks like Quarkus or vertx-mail-client issue.

https://quarkus.io/guides/mailer#configuring-the-mailer based config

quarkus.mailer.mock=false
quarkus.mailer.from[email protected]
quarkus.mailer.host=smtp.sendgrid.net
quarkus.mailer.port=465
quarkus.mailer.ssl=true
quarkus.mailer.username=foo
quarkus.mailer.password=bar

When using miss-configured gmail setting I received {"details":"Error id ea7bfd08-69cf-4772-9b3b-f640a2de938f-1, java.util.concurrent.CompletionException: io.vertx.ext.mail.SMTPException: AUTH PLAIN failed: 535-5.7.8 Username and Password not accepted. Learn more at","stack":"java.util.concurrent.CompletionException: io.vertx.ext.mail.SMTPException: AUTH PLAIN failed: 535-5.7.8 Username and Password not accepted. Learn more at\n535 5.7.8 https://support.google.com/mail/?p=BadCredentials h20-200 ....

So maybe sendgrid doesn't provide any text response like gmail and thus quarkus app still keeps the connection open / curl command doesn't finish. but logs are indicating that authentication wasn't successful and thus the connection for curl should be closed with appropriate response code / response text.

Expected behavior

endpoint invocation doesn't stay blocked

Actual behavior

endpoint invocation stays blocked

How to Reproduce?

• use mailer-quickstart
• adjust application.properties
  • config described above
• run the app - e.g. mvn clean quarkus:dev
• run curl localhost:8080/mail

Output of uname -a or ver

macOS Monterey

Output of java -version

Java 17

GraalVM version (if different from Java)

No response

Quarkus version or git rev

Quarkus main

Build tool (ie. output of mvnw --version or gradlew --version)

No response

Additional information

No response

[rsvoboda]

/cc @cescoffier

[quarkus-bot]

/cc @cescoffier

[gsmet]

Probably a good idea to get a stacktrace of the stuck thread.

[rsvoboda]

Full thread dump by jstack command - jstack.txt

[cescoffier]

So... there is a bug and a workaround.
The is a bug in the Vert.x Mailer which emits auth command asynchronously when there is a chain, but seems to forget to report in some cases. I will open an issue on the Vert.x mailer (@vietj for your info).

The workaround consists of not using auth chain, and just adding:

quarkus.mailer.auth-methods=LOGIN

[cescoffier]

Issue opened: vert-x3/vertx-mail-client#186

[cescoffier]

Fixed proposed: vert-x3/vertx-mail-client#187.

[cescoffier]

Closed by #28323