/// <summary>
/// Allows callers to add a service via HTTP requests by providing a
/// specially formatted service description.
/// </summary>
public static async Task AddService(HttpContext context, Func <Task> next)
{
RequiresArgument.NotNull(context, "context");
RequiresArgument.NotNull(next, "next");
if (!context.Request.Matches("POST", "/__vs/services"))
{
await next.Invoke();
return;
}
var serviceDesc = await ParseServiceDescription(context.Request);
RequestRequires.NotNullOrWhiteSpace(serviceDesc.Method, "An HTTP method, i.e. GET, POST, PUT, DELETE, etc., must be provided");
RequestRequires.NotNullOrWhiteSpace(serviceDesc.Path, "A path must be provided. For example /api/myResources/53");
var service = new Service(serviceDesc);
if (services.TryAdd(service))
{
await context.Response.Ok(service.Id.ToString());
}
else
{
throw new BadRequestException("Unable to add service. A service with the same ID or the same request filter already exists.");
}
}
/// <summary>
/// Allows callers to query a service via HTTP to obtain information such as
/// the number of times the service has been invoked and the body of the
/// last request message that was used to invoke the service.
/// </summary>
public static async Task QueryService(HttpContext context, Func <Task> next)
{
RequiresArgument.NotNull(context, "context");
RequiresArgument.NotNull(next, "next");
if (context.Request.Method.ToUpperInvariant() != "GET" ||
!IsAServicePath(context.Request.Path, out Guid serviceId))
{
await next.Invoke();
return;
}
if (services.TryGetById(serviceId, out Service service))
{
var stats = service.Stats;
var responseBody = new StringBuilder()
.AppendLine($"CallCount: {stats.CallCount}")
.AppendLine()
.AppendLine("LastRequestBody:")
.Append(stats.LastRequestBody)
.ToString();
await context.Response.Ok(responseBody);
}
else
{
context.Response.NotFound();
}
}
public void RequiresArgument_LengthEquals_ThrowsOnWrongSizeArray()
{
// Arrange
var arr = new[] { 1, 2 };
// Act
RequiresArgument.LengthEquals(arr, 3, "Array should contain 3 elements.");
}
/// <summary>
/// Writes the services predefined response to the specified
/// HttpResponse.
/// </summary>
public async Task WriteResponseTo(HttpResponse response)
{
RequiresArgument.NotNull(response, "response");
response.StatusCode = this.response.StatusCode;
response.ContentType = this.response.ContentType;
await response.WriteAsync(this.response.Body);
}
/// <summary>
/// Returns true if the specified service will respond to the same
/// requests as this one.
/// </summary>
public bool HandlesSameRequests(Service other)
{
RequiresArgument.NotNull(other, "other");
return(method == other.method &&
path == other.path &&
bodyFilter == other.bodyFilter);
}
public void RequiresArgument_LengthEquals_DoesNothingOnRightSizeArray()
{
// Arrange
var arr = new[] { 1, 2, 3 };
// Act
RequiresArgument.LengthEquals(arr, 3, "Array should contain 3 elements.");
}
/// <summary>
/// Returns true if the collection contains the specified service.
/// </summary>
public bool Contains(Service service)
{
RequiresArgument.NotNull(service, "service");
lock (thisLock)
{
return(internalCollection.Contains(service));
}
}
/// <summary>
/// Updates the service's Stats to reflect the fact that the service
/// has been invoked.
/// </summary>
public void RecordCall(string requestBody)
{
RequiresArgument.NotNull(requestBody, "requestBody");
lock (thisLock)
{
callCount++;
lastRequestBody = requestBody;
}
}
/// <summary>
/// Gets the first service in the collection that matched the
/// specified predicate. Returns true if a service is found;
/// otherwise false.
/// </summary>
public bool TryGetWhere(Func <Service, bool> predicate, out Service service)
{
RequiresArgument.NotNull(predicate, "predicate");
lock (thisLock)
{
service = internalCollection.FirstOrDefault(predicate);
return(service != null);
}
}
/// <summary>
/// Returns true when the service's method, path, and body filter
/// match the specified request and body.
/// </summary>
public bool MatchesRequest(HttpRequest request, string body)
{
// This method is called in a loop. While is it possible to read
// the body from the request itself, it would be very inefficient.
// For this reason, the body is required as a separate argument
// to the method.
RequiresArgument.NotNull(request, "request");
RequiresArgument.NotNull(body, "body");
return(method == request.Method &&
path == WebUtility.UrlDecode(request.Path + request.QueryString).ToUpperInvariant() &&
MatchesBodyFilter(body));
}
/// <summary>
/// Allow callers to delete all services via HTTP. This is useful for
/// cleaning up after a set of tests have been run.
/// </summary>
public static Task DeleteAllServices(HttpContext context, Func <Task> next)
{
RequiresArgument.NotNull(context, "context");
RequiresArgument.NotNull(next, "next");
if (!context.Request.Matches("DELETE", "/__vs/services"))
{
return(next.Invoke());
}
services.Clear();
context.Response.Ok();
return(Task.CompletedTask);
}
/// <summary>
/// Allows callers to delete a service via HTTP using the service's ID.
/// </summary>
public static Task DeleteService(HttpContext context, Func <Task> next)
{
RequiresArgument.NotNull(context, "context");
RequiresArgument.NotNull(next, "next");
if (context.Request.Method.ToUpperInvariant() != "DELETE" ||
!IsAServicePath(context.Request.Path, out Guid serviceId))
{
return(next.Invoke());
}
services.TryRemove(serviceId);
context.Response.Ok();
return(Task.CompletedTask);
}
/// <summary>
/// Allows callers to invoke services that have been added.
/// </summary>
public static async Task InvokeService(HttpContext context, Func <Task> next)
{
RequiresArgument.NotNull(context, "context");
RequiresArgument.NotNull(next, "next");
string body = context.Request.ReadBody();
if (services.TryGetWhere(x => x.MatchesRequest(context.Request, body), out Service service))
{
service.RecordCall(body);
await service.WriteResponseTo(context.Response);
}
else
{
context.Response.NotFound();
}
}
/// <summary>
/// Attempts to add a service to the collection. Returns true if the
/// service is added. Returns false when another service either has
/// the same ID or handles the same requests.
/// </summary>
public bool TryAdd(Service service)
{
RequiresArgument.NotNull(service, "service");
lock (thisLock)
{
if (internalCollection.Any(x =>
x.Id == service.Id ||
x.HandlesSameRequests(service)
))
{
return(false);
}
else
{
internalCollection.Add(service);
return(true);
}
}
}
/// <summary>
/// Creates a new service using the specified service description. See
/// the ServiceDesc class for more information.
/// </summary>
public Service(ServiceDesc desc)
{
RequiresArgument.NotNullOrWhiteSpace(desc.Method, "Method");
RequiresArgument.NotNullOrWhiteSpace(desc.Path, "Path");
RequiresArgument.NotNullOrWhiteSpace(desc.ContentType, "ContentType");
RequiresArgument.NotNullOrWhiteSpace(desc.StatusCode, "StatusCode");
RequiresArgument.NotNull(desc.Body, "Body");
thisLock = new object();
Id = ParseId(desc.Id);
// The method and path values are use for string matching, so
//convert them to upper invariant.
method = desc.Method.ToUpperInvariant();
path = desc.Path.ToUpperInvariant();
bodyFilter = desc.BodyContains;
response = new ServiceResponse()
{
Body = desc.Body,
ContentType = desc.ContentType,
StatusCode = ParseStatusCode(desc.StatusCode)
};
callCount = 0;
lastRequestBody = string.Empty;
}
public void RequiresArgument_NotNull_ThrowsOnNullValue()
{
// Act
RequiresArgument.NotNull(null, "Value cannot be null.");
}
public void RequiresArgument_NotNull_DoesNothingOnNonNullValue()
{
// Act
RequiresArgument.NotNull(new object(), "Value cannot be null.");
}
public void RequiresArgument_NotNullOrWhiteSpace_ThrowsOnNullOrWhiteSpaceValue()
{
// Act
RequiresArgument.NotNullOrWhiteSpace(" \t ", "Value cannot be null or white space.");
}
public void RequiresArgument_NotNullOrWhiteSpace_DoesNothingOnNonNullValue()
{
// Act
RequiresArgument.NotNullOrWhiteSpace("lorem ipsum", "Value cannot be null.");
}
