gRPC Netty with TLS failing on Android API < 24

What version of gRPC-Java are you using?

The current latest: 1.31.1, although it’s probably present in earlier versions.

What is your environment?

Android

What did you expect to see?

Being able to use NettyChannelBuilder with TLS negotiation type on Android devices with API levels 16+.

What did you see instead?

The client crashes with the following error on Android devices under API 24:

java.lang.NoSuchMethodError: No virtual method setEndpointIdentificationAlgorithm(Ljava/lang/String;)V in class Ljavax/net/ssl/SSLParameters; or its super classes (declaration of 'javax.net.ssl.SSLParameters' appears in /system/framework/core-libart.jar)"

This is the offending call: https://github.com/grpc/grpc-java/blob/master/netty/src/main/java/io/grpc/netty/ProtocolNegotiators.java#L350

SSLParameters#setEndpointIdentificationAlgorithm is only available in Android 24+.

Steps to reproduce the bug

Create a client gRPC Netty client with a TLS connection and try connecting to a server. Example:

TestServiceGrpc.newStub(
    NettyChannelBuilder
        .forAddress(InetSocketAddress("0.0.0.0", 1234))
        .useTransportSecurity()
        .build()
)

[sdsantos]

Thanks for all the help. Might be worth adding this gotchas to the documentation. At least that client-side gRPC Netty is not working right now on Android API < 24.

[ericgribkoff]

@gnarea Great, thanks for the update.

We’re switching to OkHTTP since that’s what you recommend on Android anyway. That channel doesn’t call setEndpointIdentificationAlgorithm but presumably OkHTTP does because the host name is verified.

Correct, the OkHttp code was developed well before API 24, so hostname validation is done “manually” in the OkHttp code path itself.