Super fast, platform independent, standalone component for mocking GRPC services using WireMock.NET stubbing engine
| Pattern | Implementation status |
|---|---|
| request-reply | âś… |
| server-streaming | âś… |
| client-streaming | âś… |
| duplex-streaming | âś… |
GRPC-Mock-Server works in the following way:
- compile provided
*.protofiles - generate proxy for every service and method defined in the
*.protofiles - use the generated proxy to translate GRPC calls to REST and forward it to
WireMockbackend
sequenceDiagram
participant Tests
participant TestedApp as Tested App
box GRPC-Mock-Server
participant Frontend as Fronted [GRPC to HTTP proxy]
participant Backend as Backend [WireMock]
end
autonumber
Tests->> Backend : Prepare mapping
Tests->> TestedApp: call
activate TestedApp
TestedApp->>Frontend: Call GRPC service
activate Frontend
Frontend ->> Frontend: Translate GRPC to HTTP
Frontend ->> Backend: Forward HTTP request to WireMock
activate Backend
Backend -->> Frontend: Respond with matched HTP request
deactivate Backend
Frontend ->> Frontend: Translate HTTP to GRPC
Frontend -->> TestedApp : Return GRPC response
deactivate Frontend
deactivate TestedApp
docker run -it -p 5033:5033 -p 9095:9095 -v $(pwd)/protos:/protos cezarypiatek/grpc-mock-server
Ports:
- 5033 for GRPC
- 9095 for Stubbing (WireMock API)
TestContainerGrpcMockServerConnector uses Testcontainers for .NET to spin docker container directly from the C# code. This options requires docker service running locally.
await using var connector = new TestContainerGrpcMockServerConnector(protoDirectory: "protos", grpcPort:5033);
await connector.Install();TestChartGrpcMockServerConnector uses SmoothSailing to deploy GRPC-Mock-Server into Kubernetes cluster directly from the C# code. This option requires Helm and kubectl to be installed on the host machine.
stateDiagram-v2
state "K8s Installation" as g1
state "Pod startup" as g2
state "Runtime" as g3
state "Converts proto files to ConfigMap" as s1
state "Installs Helm Chart with GRPC-Mock-Server" as s2
state "Mounts ConfigMap with protos as storage to pod" as s22
state "Compiles proto files" as s3
state "Generates GRPC-To-HTTP proxy" as s4
state "Compiles generated code" as s5
state "Starts host app with GRPC-To-HTTP proxy and WireMock" as s6
state "Handles GRPC calls" as s7
state "Handles WireMock calls" as s8
direction LR
g1 --> g2
g2 --> g3
state g1
{
direction TB
s1 --> s2
s2 --> s22
}
state g2 {
direction TB
s3 --> s4
s4 --> s5
s5 --> s6
}
state g3{
direction TB
s7
s8
}
var settings = new TestChartGrpcMockServerConnectorSettings
{
ProtoDirectory = "protos",
GrpcPort = 8889,
ExposeStubbingPortOnLocalhost = true
};
await using var connector = new TestChartGrpcMockServerConnector(settings);
var connectionInfo = await connector.Install();
All C# components required for Option 2 and Option 3 are provided by GrpcTestKit nuget package .
dotnet add package GrpcTestKit
- Add the following nuget package references
<ItemGroup>
<PackageReference Include="Grpc.AspNetCore" Version="2.53.0" />
<PackageReference Include="WireMock.Net" Version="1.5.25" />
<PackageReference Include="GrpcTestKit" Version="1.18.0" />
</ItemGroup>- Include your proto files
<ItemGroup>
<Protobuf Include="protos\**\*.proto" ProtoRoot="protos" GrpcServices="Server" />
</ItemGroup>- Define partial class for your mock server
[GrpcMockServerForAutoDiscoveredSourceServices]
public partial class MyInMemoryGrpcMockServer
{
}- Use geneated mock server type
await using var mockServer = new MyInMemoryGrpcMockServer(grpcPort: 5033, wireMockPort: 9096);
var connectionInfo = await mockServer.Install();- Add the following nuget package references
<ItemGroup>
<PackageReference Include="Grpc.AspNetCore" Version="2.53.0" />
<PackageReference Include="WireMock.Net" Version="1.5.25" />
<PackageReference Include="GrpcTestKit" Version="1.18.0" />
</ItemGroup>- Define partial class for your mock server
[GrpcMockServerFor(typeof(Sample.SampleBase))]
public partial class MyInMemoryGrpcMockServer
{
}- Use geneated mock server type
await using var mockServer = new MyInMemoryGrpcMockServer(grpcPort: 5033, wireMockPort: 9096);
var connectionInfo = await mockServer.Install();await using var connector = new TestContainerGrpcMockServerConnector( protoDirectory: "protos", grpcPort:5033);
await connector.Install();
var grpcMockClient = connector.CreateClient();
await grpcMockClient.MockRequestReply
(
serviceName: "my.package.Sample",
methodName: "TestRequestReply",
request: new { name = "Hello 1" },
response: new { message = "Hi there 1" }
);
await grpcMockClient.MockRequestReply
(
serviceName: "my.package.Sample",
methodName: "TestRequestReply",
request: new { name = "Hello 2" },
response: new { message = "Hi there 2" }
);
await grpcMockClient.MockServerStreaming
(
serviceName: "my.package.Sample",
methodName: "TestServerStreaming",
request: new { name = "Hello streaming" },
response: new[]
{
new {message = "Hi there 1"},
new {message = "Hi there 2"},
new {message = "Hi there 3"}
}
);
await grpcMockClient.MockClientStreaming
(
serviceName: "my.package.Sample",
methodName: "TestServerStreaming",
requests: new []
{
new { name = "Hello streaming 1" },
new { name = "Hello streaming 2" }
},
response: new { message = "Hi there streaming client" }
);
await grpcMockClient.MockDuplexStreaming
(
serviceName: "my.package.Sample",
methodName: "TestClientServerStreaming",
scenario: new MessageExchange[]
{
new ()
{
Requests = new[]
{
new {name = "Ping 1a"},
new {name = "Ping 1b"}
},
Responses = new[]
{
new {message = "Pong 1"}
}
},
new ()
{
Requests = new[]
{
new {name = "Ping 2"},
},
Responses = new[]
{
new {message = "Pong 2a"},
new {message = "Pong 2b"}
}
},
});You can also generate stub helpers that will simplify your code responsible for preparing mocks/stubs.
[GrpcMockHelperFor(typeof(Sample.SampleBase))]
public partial class SampleMockHelper
{
}Now you can prepare your mocks as follows:
await using var connector = new InMemoryGrpcMockServerConnector(grpcPort:5033, wireMockPort: 9594);
_ = await connector.Install();
var grpcMockClient = connector.CreateClient();
var mockHelper = new SampleMockHelper(grpcMockClient);
_ = await mockHelper.MockTestRequestReply
(
request: new HelloRequest {Name = "Hello 1"},
response: new HelloReply {Message = "Hi there 1"}
);
_ = await mockHelper.MockTestServerStreaming
(
request: new HelloRequest {Name = "Hello streaming"},
response: new[]
{
new HelloReply {Message = "Hi there 1"},
new HelloReply {Message = "Hi there 2"},
new HelloReply {Message = "Hi there 2"},
}
);
_ = await mockHelper.MockTestClientStreaming
(
request: new []
{
new HelloRequest {Name = "Hello streaming 1"},
new HelloRequest {Name = "Hello streaming 2"},
},
response: new HelloReply
{
Message = "Hi there streaming client"
}
);
_ = await mockHelper.MockTestClientServerStreaming(new MessageExchange<HelloRequest, HelloReply>[]
{
new()
{
Requests = new HelloRequest[]
{
new() {Name = "Ping 1a"},
new() {Name = "Ping 1b"}
},
Responses = new HelloReply[]
{
new() {Message = "Pong 1"}
}
},
new()
{
Requests = new HelloRequest[]
{
new() {Name = "Ping 2"},
},
Responses = new HelloReply[]
{
new() {Message = "Pong 2a"},
new() {Message = "Pong 2b"}
}
},
});- Implement error response codes
- Stub generator
- Publish source generator as nuget package to allow for hosting GRPC-Mock-Server in-process
- Implement library that wraps WireMock API for stubbing
- Implement test container