The gRPC bridge sandbox is an example usage of Envoy’s gRPC bridge filter. Included in the sandbox is a gRPC in-memory Key/Value store with a Python HTTP client. The Python client makes HTTP/1 requests through the Envoy sidecar process which are upgraded into HTTP/2 gRPC requests. Response trailers are then buffered and sent back to the client as a HTTP/1 header payload.
Another Envoy feature demonstrated in this example is Envoy’s ability to do authority base routing via its route configuration.
Building the Go service¶
To build the Go gRPC service run:
$ pwd envoy/examples/grpc-bridge $ script/bootstrap $ script/build
build requires that your Envoy codebase (or a working copy thereof) is in
To run the docker compose file, and set up both the Python and the gRPC containers run:
$ pwd envoy/examples/grpc-bridge $ docker-compose up --build
Sending requests to the Key/Value store¶
To use the Python service and send gRPC requests:
$ pwd envoy/examples/grpc-bridge # set a key $ docker-compose exec python /client/client.py set foo bar setf foo to bar # get a key $ docker-compose exec python /client/client.py get foo bar # modify an existing key $ docker-compose exec python /client/client.py set foo baz setf foo to baz # get the modified key $ docker-compose exec python /client/client.py get foo baz
In the running docker-compose container, you should see the gRPC service printing a record of its activity:
grpc_1 | 2017/05/30 12:05:09 set: foo = bar grpc_1 | 2017/05/30 12:05:12 get: foo grpc_1 | 2017/05/30 12:05:18 set: foo = baz