Scenarios and States

Scenarios

WireMock.Net supports state via the notion of scenarios. A scenario is essentially a state machine whose states can be arbitrarily assigned. Stub mappings can be configured to match on scenario state, such that stub A can be returned initially, then stub B once the next scenario state has been triggered.

For example, suppose we’re writing a to-do list application consisting of a rich client of some kind talking to a REST service. We want to test that our UI can read the to-do list, add an item and refresh itself, showing the updated list.

Example test code:

// Assign
_server = WireMockServer.Start();

_server
	.Given(Request.Create()
		.WithPath("/todo/items")
		.UsingGet())
	.InScenario("To do list")
	.WillSetStateTo("TodoList State Started")
	.RespondWith(Response.Create()
		.WithBody("Buy milk"));

_server
	.Given(Request.Create()
		.WithPath("/todo/items")
		.UsingPost())
	.InScenario("To do list")
	.WhenStateIs("TodoList State Started")
	.WillSetStateTo("Cancel newspaper item added")
	.RespondWith(Response.Create()
		.WithStatusCode(201));

_server
	.Given(Request.Create()
		.WithPath("/todo/items")
		.UsingGet())
	.InScenario("To do list")
	.WhenStateIs("Cancel newspaper item added")
	.RespondWith(Response.Create()
		.WithBody("Buy milk;Cancel newspaper subscription"));

// Act and Assert
string url = "http://localhost:" + _server.Ports[0];
string getResponse1 = await new HttpClient().GetStringAsync(url + "/todo/items");
Check.That(getResponse1).Equals("Buy milk");

var postResponse = await new HttpClient().PostAsync(url + "/todo/items", new StringContent("Cancel newspaper subscription"));
Check.That(postResponse.StatusCode).Equals(HttpStatusCode.Created);

string getResponse2 = await new HttpClient().GetStringAsync(url + "/todo/items");
Check.That(getResponse2).Equals("Buy milk;Cancel newspaper subscription");

The first Scenario and State definition can also be used in the JSON Admin interface like:

{
    "Scenario": "To do list",
    "SetStateTo": "TodoList State Started",
    "Request": {
        "Path": "/todo/items",
        "Methods": [
            "get"
        ]
    },
    "Response": {
        "StatusCode": 200,
        "Body": "Buy milk"
    }
}