Supports _type search parameter, search across all resource types, an…

…d :missing modifier (#154)

or access control, we need to the resource type to be included in the search expression tree. This also opens up the possibility of supporting the _type search parameter and searches across all resource types (/?_lastUpdated=gt2010-10-01 in addition to /Observation?_lastUpdated=gt2010-10-01).

Also makes an adjustment to the search expression trees, to explicitly state which search parameter an expression tree is bound to, by introducing a SearchParameterExpression type. Previously, there was just a convention, an implicit contract between the expression parser and the data layer. This meant that (AND (AND a b) (AND c d)) was not the same as (AND a b c d), so tree rewriting would not be a safe thing to do.

Finally, we implement support for the :missing search parameter modifier.

Resolves #152
Resolves #153

src/Microsoft.Health.Fhir.Api.UnitTests/Controllers/FhirControllerTests.cs

@@ -41,26 +41,6 @@ public FhirControllerTests()
                 _authorizationService);
         }
 
-        [Fact]
-        public void GivenUIIsSupported_WhenRequestingForRoot_ThenViewResultShouldBeReturned()
-        {
-            _featureConfiguration.SupportsUI = true;
-
-            IActionResult result = _controller.Fhir();
-
-            Assert.IsType<ViewResult>(result);
-        }
-
-        [Fact]
-        public void GivenUIIsNotSupported_WhenRequestingForRoot_ThenNotFoundResultShouldBeReturned()
-        {
-            _featureConfiguration.SupportsUI = false;
-
-            IActionResult result = _controller.Fhir();
-
-            Assert.IsType<NotFoundResult>(result);
-        }
-
         [Fact]
         public async void GivenHardDeleteActionNotAuthorized_WhenRequestingHardDeleteAction_ThenForbiddenResultShouldBeReturned()
         {

src/Microsoft.Health.Fhir.Api.UnitTests/Features/Filters/AuditLoggingFilterTests.cs

@@ -126,16 +126,18 @@ public void GivenAFhirRequest_WhenExecutingAnValidAction_ThenLogAuditMustBeCalle
         }
 
         [Theory]
-        [InlineData("Create", AuditEventSubType.Create)]
-        [InlineData("Update", AuditEventSubType.Update)]
-        [InlineData("Read", AuditEventSubType.Read)]
-        [InlineData("SystemHistory", AuditEventSubType.HistorySystem)]
-        [InlineData("TypeHistory", AuditEventSubType.HistoryType)]
-        [InlineData("History", AuditEventSubType.HistoryInstance)]
-        [InlineData("VRead", AuditEventSubType.VRead)]
-        [InlineData("Delete", AuditEventSubType.Delete)]
-        [InlineData("Search", AuditEventSubType.SearchType)]
-        [InlineData("SearchPost", AuditEventSubType.SearchType)]
+        [InlineData(nameof(FhirController.Create), AuditEventSubType.Create)]
+        [InlineData(nameof(FhirController.Update), AuditEventSubType.Update)]
+        [InlineData(nameof(FhirController.Read), AuditEventSubType.Read)]
+        [InlineData(nameof(FhirController.SystemHistory), AuditEventSubType.HistorySystem)]
+        [InlineData(nameof(FhirController.TypeHistory), AuditEventSubType.HistoryType)]
+        [InlineData(nameof(FhirController.History), AuditEventSubType.HistoryInstance)]
+        [InlineData(nameof(FhirController.VRead), AuditEventSubType.VRead)]
+        [InlineData(nameof(FhirController.Delete), AuditEventSubType.Delete)]
+        [InlineData(nameof(FhirController.SearchByResourceType), AuditEventSubType.SearchType)]
+        [InlineData(nameof(FhirController.SearchByResourceTypePost), AuditEventSubType.SearchType)]
+        [InlineData(nameof(FhirController.Search), AuditEventSubType.SearchSystem)]
+        [InlineData(nameof(FhirController.SearchPost), AuditEventSubType.SearchSystem)]
         public void GivenAFhirRequest_WhenExecutingAnValidAction_ThenCorrectRequestSubTypeMustBeSet(string methodName, string auditEventSubType)
         {
             var executingContext = new ActionExecutingContext(

src/Microsoft.Health.Fhir.Api.UnitTests/Features/Routing/UrlResolverTests.cs

@@ -103,7 +103,7 @@ public void GivenAResource_WhenResourceUrlIsResolvedWithHistory_ThenCorrectUrlSh
         [Fact]
         public void GivenANullUnsupportedSearchParams_WhenSearchUrlIsResolved_ThenCorrectUrlShouldBeReturned()
         {
-            _urlResolver.ResolveSearchUrl(unsupportedSearchParams: null, continuationToken: null);
+            _urlResolver.ResolveSearchUrl("Patient", unsupportedSearchParams: null, continuationToken: null);
 
             ValidateUrlRouteContext(
                 "SearchResources",
@@ -247,7 +247,7 @@ private void TestAndValidateRouteWithQueryParameter(
         {
             _httpContext.Request.QueryString = new QueryString(inputQueryString);
 
-            _urlResolver.ResolveSearchUrl(unsupportedSearchParams, continuationToken);
+            _urlResolver.ResolveSearchUrl("Patient", unsupportedSearchParams, continuationToken);
 
             ValidateUrlRouteContext(
                  "SearchResources",

src/Microsoft.Health.Fhir.Api/Controllers/FhirController.cs

@@ -89,25 +89,6 @@ public FhirController(
             _featureConfiguration = uiConfiguration.Value;
         }
 
-        /// <summary>
-        /// Default page of the FHIR endpoint
-        /// </summary>
-        [ApiExplorerSettings(IgnoreApi = true)]
-        [Route("")]
-        [AllowAnonymous]
-        public IActionResult Fhir()
-        {
-            _logger.LogInformation("Default route called.");
-
-            if (_featureConfiguration.SupportsUI)
-            {
-                return View("Welcome");
-            }
-
-            // If the UI is not supported, return NotFound.
-            return new NotFoundResult();
-        }
-
         [ApiExplorerSettings(IgnoreApi = true)]
         [Route("CustomError")]
         [AllowAnonymous]
@@ -345,6 +326,29 @@ public async Task<IActionResult> Delete(string type, string id, [FromQuery]bool
             return FhirResult.NoContent().SetETagHeader(response.WeakETag);
         }
 
+        /// <summary>
+        /// Searches across all resource types.
+        /// </summary>
+        [Route("", Name = RouteNames.SearchAllResources)]
+        [AuditEventSubType(AuditEventSubType.SearchSystem)]
+        [Authorize(PolicyNames.ReadPolicy)]
+        public async Task<IActionResult> Search()
+        {
+            return await SearchByResourceType(type: null);
+        }
+
+        /// <summary>
+        /// Searches for resources.
+        /// </summary>
+        [HttpPost]
+        [Route(KnownRoutes.Search, Name = RouteNames.SearchAllResourcesPost)]
+        [AuditEventSubType(AuditEventSubType.SearchSystem)]
+        [Authorize(PolicyNames.ReadPolicy)]
+        public async Task<IActionResult> SearchPost()
+        {
+            return await SearchByResourceTypePost(type: null);
+        }
+
         /// <summary>
         /// Searches for resources.
         /// </summary>
@@ -353,7 +357,7 @@ public async Task<IActionResult> Delete(string type, string id, [FromQuery]bool
         [Route(KnownRoutes.ResourceType, Name = RouteNames.SearchResources)]
         [AuditEventSubType(AuditEventSubType.SearchType)]
         [Authorize(PolicyNames.ReadPolicy)]
-        public async Task<IActionResult> Search(string type)
+        public async Task<IActionResult> SearchByResourceType(string type)
         {
             IReadOnlyList<Tuple<string, string>> queries = Array.Empty<Tuple<string, string>>();
 
@@ -374,7 +378,7 @@ public async Task<IActionResult> Search(string type)
         [Route(KnownRoutes.ResourceTypeSearch, Name = RouteNames.SearchResourcesPost)]
         [AuditEventSubType(AuditEventSubType.SearchType)]
         [Authorize(PolicyNames.ReadPolicy)]
-        public async Task<IActionResult> SearchPost(string type)
+        public async Task<IActionResult> SearchByResourceTypePost(string type)
         {
             var queries = new List<Tuple<string, string>>();
 

src/Microsoft.Health.Fhir.Api/Features/Filters/ValidateContentTypeFilterAttribute.cs

@@ -46,9 +46,18 @@ public override async Task OnActionExecutionAsync(ActionExecutingContext context
                 {
                     var resourceFormat = ContentType.GetResourceFormatFromContentType(headerValue[0]);
 
-                    if (!await _contentTypeService.IsFormatSupportedAsync(resourceFormat) && context.ActionDescriptor?.AttributeRouteInfo?.Name != RouteNames.SearchResourcesPost)
+                    if (!await _contentTypeService.IsFormatSupportedAsync(resourceFormat))
                     {
-                        throw new UnsupportedMediaTypeException(Resources.UnsupportedContentTypeHeader);
+                        string routeName = context.ActionDescriptor?.AttributeRouteInfo?.Name;
+
+                        switch (routeName)
+                        {
+                            case RouteNames.SearchResourcesPost:
+                            case RouteNames.SearchAllResourcesPost:
+                                break;
+                            default:
+                                throw new UnsupportedMediaTypeException(Resources.UnsupportedContentTypeHeader);
+                        }
                     }
                 }
                 else

src/Microsoft.Health.Fhir.Api/Features/Routing/KnownRoutes.cs

@@ -14,9 +14,10 @@ internal class KnownRoutes
         private const string VidRouteSegment = "{" + KnownActionParameterNames.Vid + "}";
 
         public const string History = "_history";
+        public const string Search = "_search";
         public const string ResourceType = ResourceTypeRouteSegment;
         public const string ResourceTypeHistory = ResourceType + "/" + History;
-        public const string ResourceTypeSearch = ResourceType + "/_search";
+        public const string ResourceTypeSearch = ResourceType + "/" + Search;
         public const string ResourceTypeById = ResourceType + "/" + IdRouteSegment;
         public const string ResourceTypeByIdHistory = ResourceTypeById + "/" + History;
         public const string ResourceTypeByIdAndVid = ResourceTypeByIdHistory + "/" + VidRouteSegment;

src/Microsoft.Health.Fhir.Api/Features/Routing/RouteNames.cs

@@ -15,12 +15,16 @@ internal static class RouteNames
 
         internal const string SearchResources = "SearchResources";
 
+        internal const string SearchAllResources = "SearchAllResources";
+
         internal const string History = "History";
 
         internal const string HistoryType = "HistoryType";
 
         internal const string HistoryTypeId = "HistoryTypeId";
 
         internal const string SearchResourcesPost = "SearchResourcesPost";
+
+        internal const string SearchAllResourcesPost = "SearchAllResourcesPost";
     }
 }

src/Microsoft.Health.Fhir.Api/Features/Routing/UrlResolver.cs

@@ -102,9 +102,9 @@ public Uri ResolveResourceUrl(Resource resource, bool includeVersion = false)
         }
 
         /// <inheritdoc />
-        public Uri ResolveSearchUrl(IEnumerable<Tuple<string, string>> unsupportedSearchParams = null, string continuationToken = null)
+        public Uri ResolveSearchUrl(string resourceType, IEnumerable<Tuple<string, string>> unsupportedSearchParams = null, string continuationToken = null)
         {
-            return ResolveRouteUrl(RouteNames.SearchResources, unsupportedSearchParams, continuationToken);
+            return ResolveRouteUrl(string.IsNullOrEmpty(resourceType) ? RouteNames.SearchAllResources : RouteNames.SearchResources, unsupportedSearchParams, continuationToken);
         }
 
         public Uri ResolveRouteUrl(string routeName, IEnumerable<Tuple<string, string>> unsupportedSearchParams = null, string continuationToken = null)

src/Microsoft.Health.Fhir.Api/Microsoft.Health.Fhir.Api.csproj

@@ -21,7 +21,6 @@
 
   <ItemGroup>
     <EmbeddedResource Include="Views\Shared\ViewJson.cshtml" />
-    <EmbeddedResource Include="Views\Shared\Welcome.cshtml" />
     <EmbeddedResource Include="Views\Shared\_Layout.cshtml" />
     <EmbeddedResource Include="Views\_ViewImports.cshtml" />
     <EmbeddedResource Include="Views\_ViewStart.cshtml" />

src/Microsoft.Health.Fhir.Api/Modules/SearchModule.cs

@@ -52,7 +52,7 @@ public void Load(IServiceCollection services)
                 .AsService<IFhirElementToSearchValueTypeConverterManager>();
 
             services.AddSingleton<ISearchIndexer, SearchIndexer>();
-            services.AddSingleton<ISearchValueExpressionBuilder, SearchValueExpressionBuilder>();
+            services.AddSingleton<ISearchParameterExpressionParser, SearchParameterExpressionParser>();
             services.AddSingleton<IExpressionParser, ExpressionParser>();
             services.AddSingleton<ISearchOptionsFactory, SearchOptionsFactory>();
 

src/Microsoft.Health.Fhir.Core.UnitTests/Features/Definition/SearchParameterDefinitionBuilderTests.cs

@@ -85,6 +85,7 @@ public void GivenAValidSearchParameterDefinitionFile_WhenBuilt_ThenCorrectListOf
 
             ValidateSearchParameters(
                 searchParametersDictionary,
+                ("_type", SearchParamType.Token, "Resource.type().name"),
                 ("_id", SearchParamType.Token, "Resource.id"),
                 ("balance", SearchParamType.Quantity, "Account.balance"),
                 ("identifier", SearchParamType.Token, "Account.identifier"));
@@ -103,6 +104,7 @@ public void GivenAValidSearchParameterDefinitionFile_WhenBuilt_ThenCorrectListOf
 
             ValidateSearchParameters(
                 searchParametersDictionary,
+                ("_type", SearchParamType.Token, "Resource.type().name"),
                 ("_id", SearchParamType.Token, "Resource.id"),
                 ("identifier", SearchParamType.Token, "MedicationRequest.identifier | MedicationAdministration.identifier | MedicationStatement.identifier | MedicationDispense.identifier"));
         }

src/Microsoft.Health.Fhir.Core.UnitTests/Features/Search/Expressions/Parsers/ExpressionParserTests.cs

@@ -19,15 +19,15 @@ namespace Microsoft.Health.Fhir.Core.UnitTests.Features.Search.Expressions.Parse
     public class ExpressionParserTests
     {
         private readonly ISearchParameterDefinitionManager _searchParameterDefinitionManager = Substitute.For<ISearchParameterDefinitionManager>();
-        private readonly ISearchValueExpressionBuilder _searchValueExpressionBuilder = Substitute.For<ISearchValueExpressionBuilder>();
+        private readonly ISearchParameterExpressionParser _searchParameterExpressionParser = Substitute.For<ISearchParameterExpressionParser>();
 
         private readonly ExpressionParser _expressionParser;
 
         public ExpressionParserTests()
         {
             _expressionParser = new ExpressionParser(
                 _searchParameterDefinitionManager,
-                _searchValueExpressionBuilder);
+                _searchParameterExpressionParser);
         }
 
         [Fact]
@@ -243,15 +243,15 @@ public void GivenAModifier_WhenParsed_ThenExceptionShouldBeThrown()
             string param1 = "ref";
             string modifier = "missing";
 
-            // Practitioner is a valid resource type but is not supported by the search paramter.
+            // Practitioner is a valid resource type but is not supported by the search parameter.
             string key = $"{param1}:{modifier}";
             string value = "Seattle";
 
             SearchParameter searchParameter = SetupSearchParameter(resourceType, param1);
 
             Expression expression = Substitute.For<Expression>();
 
-            _searchValueExpressionBuilder.Build(searchParameter, SearchParameter.SearchModifierCode.Missing, value).Returns(expression);
+            _searchParameterExpressionParser.Parse(searchParameter, SearchParameter.SearchModifierCode.Missing, value).Returns(expression);
 
             // Parse the expression.
             Expression actualExpression = _expressionParser.Parse(resourceType, key, value);
@@ -361,7 +361,7 @@ private Expression SetupExpression(SearchParameter searchParameter, string value
         {
             Expression expectedExpression = Substitute.For<Expression>();
 
-            _searchValueExpressionBuilder.Build(searchParameter, null, value).Returns(expectedExpression);
+            _searchParameterExpressionParser.Parse(searchParameter, null, value).Returns(expectedExpression);
 
             return expectedExpression;
         }