SpringBoot: FeignClient with SSL (p12)

Question

I'm trying to create a FeignClient for one external HTTP API which uses SSL. The struggle is - how to modify default Spring FeignClient with my logic, in this case SSL Connection Factory. So basically I wanna keep all the good things Spring automatically does for the FeignClients, like Hystrix, Sleuth tracing, etc and make it work with my SSL factory.

Will appreciate any suggestions.

---

Here is what I tried to do:

I've tried to provide a custom @Configuration outside of ComponentScan:

@Configuration
public class CustomFeignConfiguration
{
    @Bean
    public Feign.Builder feignBuilder()
    {
        Client trustSSLSockets = new Client.Default(
                TrustingSSLSocketFactory.get("server1"),
                new NoopHostnameVerifier());

        log.info("feignBuilder called");
        return Feign.builder().client(trustSSLSockets);
    }
...
}

Made FeignClient use it through annotation

    @FeignClient(name = "sslClient", configuration = CustomFeignConfiguration.class, url = "https://...")

Where "TrustingSSLSocketFactory" is implemented similar to this.

Now if I inject my client in a Spring application, I can see that "feignBuilder" was called and it successfully loaded my keys. The problem is that the created client doesn't actually use the specified SSLFactory for createSocket calls. So I get:

Caused by: javax.net.ssl.SSLHandshakeException: Received fatal alert: handshake_failure
    at sun.security.ssl.Alerts.getSSLException(Alerts.java:192) ~[na:1.8.0_72]
    at sun.security.ssl.Alerts.getSSLException(Alerts.java:154) ~[na:1.8.0_72]
    at sun.security.ssl.SSLSocketImpl.recvAlert(SSLSocketImpl.java:2023) ~[na:1.8.0_72]
    at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1125) ~[na:1.8.0_72]
    at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1375) ~[na:1.8.0_72]
    at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1403) ~[na:1.8.0_72]
    at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1387) ~[na:1.8.0_72]
    at sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:559) ~[na:1.8.0_72]
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:185) ~[na:1.8.0_72]
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1513) ~[na:1.8.0_72]
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1441) ~[na:1.8.0_72]
    at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:480) ~[na:1.8.0_72]
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(HttpsURLConnectionImpl.java:338) ~[na:1.8.0_72]
    at feign.Client$Default.convertResponse(Client.java:152) ~[feign-core-9.3.1.jar:na]

Answer 1

Create the Client as it's own @Bean rather than part of the builder. builder.client(client) gets called later on, overriding the client you set while creating the builder.

So

@Bean
public Client feignClient()
{
    Client trustSSLSockets = new Client.Default(
            TrustingSSLSocketFactory.get("server1"),
            new NoopHostnameVerifier());

    log.info("feignClient called");
    return trustSSLSockets;
}

Answer 2

I did something like this which served my purpose-

@Bean
public Client feignClient()
{
    Client trustSSLSockets = new Client.Default(getSSLSocketFactory(), new NoopHostnameVerifier());
    log.info("feignClient called"); 
    return trustSSLSockets;
}


private SSLSocketFactory getSSLSocketFactory() {
    try {
    TrustStrategy acceptingTrustStrategy = new TrustStrategy() {
        @Override
        public boolean isTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            //Do your validations
            return true;
        }
        };

        SSLContext sslContext = SSLContexts.custom().loadTrustMaterial(null, acceptingTrustStrategy).build();
        return sslContext.getSocketFactory();
    } catch (Exception exception) {
        throw new RuntimeException(exception);
    }
}