Overview

grpc-wiremock is a mock server for GRPC services implemented as a wrapper around the WireMock http server.

How It Works

grpc-wiremock starts a grpc server generated based on provided proto files which will convert a proto grpc request to JSON and redirects it as a POST request to the WireMock then converts a http response back to grpc proto format.

GRPC server works on tcp://localhost:50000
WireMock server works on http://localhost:8888

Quick Usage

docker run -p 8888:8888 -p 50000:50000 -v $(pwd)/example/proto:/proto -v $(pwd)/example/wiremock:/wiremock adven27/grpc-wiremock

Stub

curl -X POST http://localhost:8888/__admin/mappings \
  -d '{
    "request": {
        "method": "POST",
        "url": "/BalanceService/getUserBalance",
        "bodyPatterns" : [ {
            "equalToJson" : { "id": "1", "currency": "EUR" }
        } ]
    },
    "response": {
        "status": 200,
        "jsonBody": { 
            "balance": { 
                "amount": { "value": { "decimal" : "100.0" }, "value_present": true },
                "currency": { "value": "EUR", "value_present": true }
            } 
        }
    }
}'

Check

grpcurl -plaintext -d '{"id": 1, "currency": "EUR"}' localhost:50000 api.wallet.BalanceService/getUserBalance

Should get response:

{
  "balance": {
    "amount": {
      "value": {
        "decimal": "100.0"
      },
      "value_present": true
    },
    "currency": {
      "value": "EUR",
      "value_present": true
    }
  }
}

Stubbing

Stubbing should be done via WireMock JSON API

How To:

1. Change grpc server properties

Currently, following grpc server properties are supported^*:

GRPC_SERVER_MAXHEADERLISTSIZE
GRPC_SERVER_MAXMESSAGESIZE
GRPC_SERVER_MAXINBOUNDMETADATASIZE
GRPC_SERVER_MAXINBOUNDMESSAGESIZE

_{*The first two are deprecated in favor of the last two}

Could be used like this:

docker run -e GRPC_SERVER_MAXHEADERLISTSIZE=1000 adven27/grpc-wiremock

2. Speed up container start

In case you don't need to change proto files, you can build your own image with precompiled protos.
See an example

3. Use with snappy compresser/decompresser

Snappy support can be enabled using EXT_CODECS env variable as follows:

docker run -e EXT_CODECS=snappy adven27/grpc-wiremock

Also in docker-compose:

    image: adven27/grpc-wiremock
    ports:
      - "12085:50000" # grpc port
      - "8088:8888" # http serve port
    volumes:
      - ./example/proto:/proto
    environment:
      - EXT_CODECS=snappy

_{*gzip compression supported by default}

4. Use in load testing

To increase performance some Wiremock related options may be tuned either directly or by enabling the "load" profile. Next two commands are identical:

docker run -e SPRING_PROFILES_ACTIVE=load adven27/grpc-wiremock

docker run \
    -e WIREMOCK_SERVER_DISABLEREQUESTJOURNAL=true \
    -e WIREMOCK_SERVER_ASYNCHRONOUSRESPONSEENABLED=true \
    -e WIREMOCK_SERVER_ASYNCHRONOUSRESPONSETHREADS=10 \
    -e WIREMOCK_SERVER_STUBREQUESTLOGGINGDISABLED=true \
    -e WIREMOCK_SERVER_VERBOSE=false \
    adven27/grpc-wiremock

linouk23/grpc-wiremock