Invalid signature in Slack API

Question

I'm trying to make a Slack App, using Bolt library. I made a simple Hello World application according to official docs: https://api.slack.com/start/building/bolt-java

Credentials I inject from properties file, that's what my SlackApp class lookalike:

@Configuration
public class SlackApp {

    private final String secret;

    private final String token;

    public SlackApp(@Value("${slack.signing-secret}") String secret,
                    @Value("${slack.bot-token}") String token) {
        this.secret = secret;
        this.token = token;

    }

    @Bean
    public App initSlackApp() {
        AppConfig config = AppConfig.builder()
                .signingSecret(secret)
                .singleTeamBotToken(token)
                .build();
        App app = new App(config);
        app.command("/hello", (req, ctx) -> {
            return ctx.ack("What's up?");
        });
        return app;
    }
}

Token and secret, I've obtained like in this part of docs: https://slack.dev/java-slack-sdk/guides/getting-started-with-bolt

But when I try to turn on Event Subscription in Slack API I got Your URL didn't respond with the value of the challenge parameter. error.

And in application logs I've got

2021-11-30 17:27:08.364 DEBUG 81561 --- [nio-3000-exec-4] c.s.a.a.SlackSignature$Verifier          : Request verification (timestamp: 1638278828, body: {"token":"VERIFICATION_TOKEN","challenge":"CHALLENGE","type":"url_verification"}, signature: v0=SIGNATURE)
2021-11-30 17:27:08.366  INFO 81561 --- [nio-3000-exec-4] c.s.a.b.m.builtin.RequestVerification    : Invalid signature detected - v0=SIGNATURE

What can be reason of invalid signature error, if both signing secret and bot token is correct?

Invalid signature in Slack API

0 Answers