README.md

Hello World

The helloworld example is a slightly modified version of the helloworld example from gRPC Java examples.

Service

To build the helloworld service, provision a WildFly server with the gRPC subsystem and any necessary certificate files, and deploy the service, run:

cd service
mvn clean package -Dssl=<SSL>

where SSL is either

• none: plaintext
• oneway: server identity is verified
• twoway: both server and client identities are verified

Then, run the server with:

./target/wildfly/bin/standalone.sh --stability preview

Client

The helloworld client is a simple Java application. To build it, run:

cd client
mvn package

This produces a fat JAR that can be launched directly:

java -jar target/helloworld-client.jar [options] [name]

Command Line Arguments

Argument	Default	Description
--ssl=<mode>	none	SSL mode: none, oneway, or twoway (defaults to none, must match the server)
name	world	Name to greet (defaults to world)

Examples

Start the server in one terminal:

cd service
mvn clean package -Dssl=none
./target/wildfly/bin/standalone.sh --stability preview

Run the client in another terminal:

cd client
java -jar target/helloworld-client.jar Bob

Using gRPCurl

Alternatively, you can use gRPCurl to invoke the service. Run these commands from the examples/helloworld directory:

# clear text connection
grpcurl -proto proto/src/main/proto/helloworld.proto \
  -plaintext \
  -d '{"name":"Bob"}' \
  localhost:9555 helloworld.Greeter/SayHello

# tls (oneway)
grpcurl -proto proto/src/main/proto/helloworld.proto \
  -cacert ../../ssl-gen/target/generated-ssl/client.truststore.pem \
  -d '{"name":"Bob"}' \
  localhost:9555 helloworld.Greeter/SayHello

# mutual TLS (twoway)
grpcurl -proto proto/src/main/proto/helloworld.proto \
  -cacert ../../ssl-gen/target/generated-ssl/client.truststore.pem \
  -cert ../../ssl-gen/target/generated-ssl/client.crt.pem \
  -key ../../ssl-gen/target/generated-ssl/client.key.pem \
  -d '{"name":"Bob"}' \
  localhost:9555 helloworld.Greeter/SayHello