TheRealReal / mock_grpc

MockGRPC

Concurrent mocks for gRPC Elixir.

Installation

Add mock_grpc to your list of dependencies:

def deps do
  [
    {:mock_grpc, "~> 0.1"},

    # You also need to have gRPC Elixir installed
    {:grpc, "~> 0.6"}
  ]
end

How to use

Imagine that you have a module calling a say_hello RPC.

defmodule Demo do
  def say_hello(name) do
    {:ok, channel} = GRPC.Stub.connect("localhost:50051")
    GreetService.Stub.say_hello(channel, %SayHelloRequest{name: "John Doe"})
  end
end

The first step is to change the connect code to use an adapter coming from the app environment, so that you can use MockGRPC in test mode, and the default adapter in dev and production.

{:ok, channel} =
  GRPC.Stub.connect(
    "localhost:50051",
    adapter: Application.get_env(:demo, :grpc_adapter)
  )

Or if you're using ConnGRPC, add adapter to the channel opts.

Then, on your config/test.exs, set it to MockGRPC.Adapter:

Application.put_env(:demo, :grpc_adapter, MockGRPC.Adapter)

Now it's time to write your test. To enable mocks, add use MockGRPC to your test, and call MockGRPC.expect/2 or MockGRPC.expect/3 to set expectations.

defmodule DemoTest do
  use ExUnit.Case, async: true

  use MockGRPC

  test "say_hello/1" do
    MockGRPC.expect(&GreetService.Stub.say_hello/2, fn req ->
      assert %SayHelloRequest{name: "John Doe"} == req
      {:ok, %SayHelloResponse{message: "Hello John Doe"}}
    end)

    assert {:ok, %SayHelloResponse{message: "Hello John Doe"}} = Demo.say_hello("John Doe")
  end
end

For more info, see MockGRPC on Hexdocs.

Code of Conduct

This project uses Contributor Covenant version 2.1. Check CODE_OF_CONDUCT.md file for more information.

License

MockGRPC source code is released under Apache License 2.0.

Check NOTICE and LICENSE files for more information.