Provide helper method to set up a condition for a query string argument

[markvincze]

We can already set up preconditions on the Route with the syntax

sut.Request(HttpMethod.Get)
    .IfRoute("/testget")
    ...

But we don't have any way to have a precondition for a specific query string argument.
(We can do .IfRoute("/testget?arg1=foo&arg2=bar"), but it's not really intuitive.)

We should introduce a new condition method called IfQueryArg, which would check the value of a specific query string argument.

Example usage:

sut.Request(HttpMethod.Get)
    .IfRoute("/testget")
    .IfQueryArg("arg1", "foo")
    .IfQueryArg("arg2", "bar")
    ...

[dstj]

I think it would also be important to support retrieving query string arguments for use in the response, similar to the Route arguments.

[markvincze]

Hey @dstj,

Sorry for the late response: I think this is already possible, you can do the following:

stub.Get(
    "/test",
    (req, args) => $"Value of query arg: {args.Query.myarg}");

Or is this not what you meant?

[dstj]

Hi @markvincze,

Does IfQueryArg() work? Because I've got the following and I see that using the querystring company/id=123 also gets in this mock...

_stub.Get()
	.IfRoute("/some/route")
	.IfQueryArg("fields", "id,name")
	.IfQueryArg("conditions", "company/id=456 and active=true")
	.Response((req, args) => {
	...

Also, I remembered what I meant by "retrieving query string arguments for use in the response, similar to the Route arguments." above. I meant doing something like this:

_stub.Get()
	.IfRoute("/some/route")
	.IfQueryArg("conditions", "company/id={companyId} and active=true")
	.Response((req, args) => {
		var companyId = args.Query.companyId
	});

[dstj]

Hi again @markvincze, here's more information. Two IfQueryArg() do not work. If one is met, then the others seems ignored (order of IfQueryArg() do not seems relevant).

Here's a simple example to reproduce the problem:

public class TestClass
{
	private Stub _stub;

	[SetUp]
	public void SetUp()
	{
		_stub = new Stub();
		_stub.Start();
	}

	[TearDown]
	public void TearDown()
	{
		_stub.Dispose();
	}

	[TestCase("123", "123")]
	[TestCase("456", "456")]
	[TestCase("789", "catch all")]
	public async Task GetWithQueryArgs(string id, string expectation)
	{
		var encodedConditions = HttpUtility.UrlEncode($"company/id={id}");
		var uri = $"{_stub.Address}/test?fields=name&conditions={encodedConditions}";

		using (var httpClient = new HttpClient())
		using (var httpMessage = new HttpRequestMessage(HttpMethod.Get, uri))
		using (var httpResponse = await httpClient.SendAsync(httpMessage)) {
			var actual = await httpResponse.Content.ReadAsStringAsync();
			Assert.AreEqual(expectation, actual);
		}
	}
}

public class Stub : Stubbery.ApiStub
{
	public Stub()
	{
		Get()
			.IfRoute("/test")
			.IfQueryArg("fields", "name")
			.IfQueryArg("conditions", "company/id=123")
			.Response((req, args) => "123");

		Get()
			.IfRoute("/test")
			.IfQueryArg("fields", "name")
			.IfQueryArg("conditions", "company/id=456")
			.Response((req, args) => "456");

		Get()
			.Response((req, args) => "catch all");
	}
}

[markvincze]

Hi @dstj,

This example:

_stub.Get()
	.IfRoute("/some/route")
	.IfQueryArg("fields", "id,name")
	.IfQueryArg("conditions", "company/id=456 and active=true")
	.Response((req, args) => {
	...

I'm not sure I understand. You expect the "company/id=456 and active=true" string to be interpreted as some sort of query language? The library cannot do anything like that at the moment, it just takes it as a string verbatim.
So in this case it would match if the query string argument condition contained the value company%2Fid%3D456%20and%20active%3Dtrue.

I understand the other issue about anding and oring conditions together, I'll try to think of a way to introduce this in the interface somehow, I'll keep you updated.

[dstj]

@markvincze, true, I guess the real problem with the conditions=company/id=456 and active=true is not Stuberry but the actual server API itself that uses complex querystring parsing rules. Let's drop this. ;)

Thanks for thinking about the OR and AND issue.