gRPC Java boilerplate application ( build in gradle )

To Generate Proto

./gradlew generateProto

Structure:

src/main/proto

Proto definitions

src/main/java

Java implementation for gRPC based on gRPC generated code

docker-build

File to build an image based on the application

deploy

Files to deploy the application in a Kubernetes cluster with Istio

googleapis

Files necessary to build .pb file, source "https://github.com/googleapis/googleapis"

Run the server

br.com.amsj.grpc.calculator.server.CalculatorServer

gRPC client streaming

br.com.amsj.grpc.calculator.client.AverageServerStreamClient

gRPC unary call with error handling

br.com.amsj.grpc.calculator.client.SquareRootUnaryClient

gRPC Reflections

Reference: https://github.com/grpc/grpc-java/blob/master/documentation/server-reflection-tutorial.md

configuration

build.gradle

Test With evans ( Install evans is needed )

1. Install evans

https://github.com/ktr0731/evans#installation

2. Start the server

3.1 ( WITHOUT DISCOVERY ) Run Evans looking for proto file:

evans --proto <PATH-TO-PROTO-FILE> --port <PORT> --host <HOST>
evans --proto calculator.proto --port 50081 --host localhost

3.2 ( USING DISCOVERY ) Run Evans looking for proto file:

evans --host <LOCALHOST> -p <PORT> -r
evans --host localhost -p 50081 -r

4. Discovery the services

show services

5. Call some service

call <SERVICE-NAME>
call CalculatorSquareRoot
call CalculatorAverage

Tip:

To stop input streaming on Evans use "CTRL+D"

Test with BloomRPC

Add .protofile and use "Unary Call" for ">:<GRPC-NODE/LOAD-BALANCER-PORT>" example:

localhost:50081

Deploy on Kubernetes ( Use for Istio - Service Mesh )

To build a docker image ( linux/amd64 and linux/arm64 ):

docker buildx build -t <YOUR-DOCKERHUB-USER>/calculatorgrpc --platform linux/arm64,linux/amd64 --push -f docker-build/Dockerfile .

To consume use the Load Balancer for port 5000, or create Node port for Istio expose the application

To configure the transcoder

create a .pb file based on proto

protoc -Igoogleapis/ -I. --include_imports --include_source_info --descriptor_set_out=src/main/proto/calculator/proto.pb src/main/proto/calculator/calculator.proto

To create the config map for transcoder from .pb file

kubectl -n calculatorgrpc create cm proto-descriptor --from-file=src/main/proto/calculator/proto.pb --dry-run=client -o yaml > deploy/06-calculatorgrpc-cm-proto.yaml

To deploy on Kubernetes Cluster with Istio

( It is Needed change the file deploy/05-calculatorgrpc-deploy.yaml to your image - Optional ):

kubectl apply -f deploy/

Tests

Test with BloomRPC

Add .protofile andSET THE URL for ">:<GRPC-NODE/LOAD-BALANCER-PORT>" example:

"calculatorgrpc.teste.com.br:30119"

Request for CalculatorSquareRoot ( unary )

{
"number": 81
}

Request for CalculatorSum ( unary )

{
  "numbers": [
    10,
    20,
    30
  ]
}

Request for CalculatorAverage ( streaming )

{
  "number": 10
}

Transcoder Rest > gRPC - ( Istio - Service Mesh ) - Using cURL

CalculatorSquareRoot

curl --location --request GET 'https://<SERVICE-DNS>>:<HTTPS-PORT>>/v1/calculatorsquareroot/<SOME-INTEGER>', example "https://calculatorgrpc.teste.com.br:31767/v1/calculatorsquareroot/81" --header 'Content-Type: application/json'

example:

curl --location --request GET 'https://calculatorgrpc.teste.com.br:31767/v1/calculatorsquareroot/81' --header 'Content-Type: application/json'

CalculatorSum

curl --location --request POST 'https://<SERVICE-DNS>:<HTTPS-PORT>/v1/calculatorsum' --header 'Content-Type: text/plain' \
--data-raw '[<ARRAY-INTEGER>]'

example:

curl --location --request POST 'https://calculatorgrpc.teste.com.br:31767/v1/calculatorsum' --header 'Content-Type: text/plain' \
--data-raw '  [
    10,
    20,
    30,
    30
  ]
'

CalculatorAverage

curl --location --request POST 'https://<SERVICE-DNS>:<HTTPS-PORT>/v1/calculatorsquareroot/calculatoraverage' --header 'Content-Type: text/plain' \
--data-raw '[<ARRAY-INTEGER>]'

example:

curl --location --request POST 'https://calculatorgrpc.teste.com.br:31767/v1/calculatoraverage' --header 'Content-Type: text/plain' \
--data-raw '  [
    10,
    20,
    30,
    30,
    10
  ]
'

Tip use curl -k to contour certificate problems

Transcoder Rest > gRPC - ( Istio - Service Mesh ) - Using cURL

CalculatorSquareRoot

curl --location --request GET 'https://<SERVICE-DNS>>:<HTTPS-PORT>>/v1/calculatorsquareroot/<SOME-INTEGER>', example "https://calculatorgrpc.teste.com.br:31767/v1/calculatorsquareroot/81" --header 'Content-Type: application/json'

example:

curl --location --request GET 'https://calculatorgrpc.teste.com.br:31767/v1/calculatorsquareroot/81' --header 'Content-Type: application/json'

CalculatorSum

curl --location --request POST 'https://<SERVICE-DNS>:<HTTPS-PORT>/v1/calculatorsum' --header 'Content-Type: text/plain' \
--data-raw '[<ARRAY-INTEGER>]'

example:

curl --location --request POST 'https://calculatorgrpc.teste.com.br:31767/v1/calculatorsum' --header 'Content-Type: text/plain' \
--data-raw '  [
    10,
    20,
    30,
    30
  ]
'

CalculatorAverage

curl --location --request POST 'https://<SERVICE-DNS>:<HTTPS-PORT>/v1/calculatorsquareroot/calculatoraverage' --header 'Content-Type: text/plain' \
--data-raw '[<ARRAY-INTEGER>]'

example:

curl --location --request POST 'https://calculatorgrpc.teste.com.br:31767/v1/calculatoraverage' --header 'Content-Type: text/plain' \
--data-raw '  [
    10,
    20,
    30,
    30,
    10
  ]
'

Tip use curl -k to contour certificate problems