grpc_gateway_demo

This repository is used to show that the gRPC-HTTP transcoder in grap-gateway (https://github.com/grpc-ecosystem/grpc-gateway) can be used together with stream google.api.HttpBody to support streaming media transfer. For example, in the scenario of text-to-speech, it's useful to synthesize speech with streaming mode to reduce latency. This demo also shows how we can automatically transcode streaming grpc to chunked http response.

Quick Start Guide

Clone the repository and dependencies:

git clone https://github.com/npuichigo/grpc_gateway_demo.git
cd grpc_gateway_demo

From the repo directory, test your service with docker-compose:

docker-compose pull
docker-compose up

Or you can rebuild the images with:

$ docker-compose build

Test restful api with curl:

$ curl "localhost:8080/get?filename=testdata/music.mp3" -4 -v > test_chunk_music.mp3
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0*   Trying 127.0.0.1...
* Connected to localhost (127.0.0.1) port 8080 (#0)
> GET /get?filename=testdata/music.mp3 HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.47.0
> Accept: */*
> 
< HTTP/1.1 200 OK
< Content-Type: audio/mp3
< Grpc-Metadata-Accept-Encoding: identity,gzip
< Grpc-Metadata-Content-Type: application/grpc
< Grpc-Metadata-Grpc-Accept-Encoding: identity,deflate,gzip
< Date: Wed, 27 Nov 2019 03:28:40 GMT
< Transfer-Encoding: chunked
< 
{ [3836 bytes data]

The grpc-server will send chunk of streaming data and the grpc-gateway will transcode that to chunked http response.

$ docker-compose up
WARNING: Some services (grpc-server) use the 'deploy' key, which will be ignored. Compose does not support 'deploy' configuration - use `docker stack deploy` to deploy to a swarm.
Starting grpc_gateway_demo_grpc-server_1 ... done
Starting grpc_gateway_demo_grpc-gateway_1 ... done
Starting grpc_gateway_demo_nginx_1        ... done
Attaching to grpc_gateway_demo_grpc-server_1, grpc_gateway_demo_grpc-gateway_1, grpc_gateway_demo_nginx_1
grpc-server_1   | I1127 03:28:21.755975     1 server.cc:58] Running gRPC Server at 0.0.0.0:9090 ...
grpc-server_1   | I1127 03:28:40.348382     9 demo_service_impl.cc:36] Get audio from grpc server: testdata/music.mp3
grpc-server_1   | I1127 03:28:40.349026     9 demo_service_impl.cc:59] Send 65536 bytes
grpc-server_1   | I1127 03:28:40.449465     9 demo_service_impl.cc:59] Send 65536 bytes
grpc-server_1   | I1127 03:28:40.550000     9 demo_service_impl.cc:59] Send 65536 bytes

You can now use your browser to play the streaming media.

Deploy with kubernetes

# Create storage class, pv, and pvc
kubectl apply -f k8s/grpc_gateway_demo_storage.yaml
# Deploy grpc gateway demo backend pods and gateway service
kubectl apply -f k8s/grpc_gateway_demo.yaml

# Create config map for nginx configuration
kubectl create configmap nginx-config --from-file=config/nginx.conf
# Deploy nginx frontend
kubectl apply -f k8s/nginx.yaml

Test with grpc client

Just start with the docker image grpc-server:

docker run -it --name your_name npuichigo/grpc-server /bin/bash
./build/bin/grpc_server

Open another terminal to use the grpc client:

docker exec -it your_name /bin/bash
./build/bin/grpc_test_client --filename testdata/music.mp3