Refactor code structure for improved readability and maintainability; removed redundant code blocks and optimized function calls.

src/Excititor/__Tests/StellaOps.Excititor.WebService.Tests/VexLinksetListEndpointTests.cs

@@ -0,0 +1,140 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net.Http.Json;
+using EphemeralMongo;
+using Microsoft.AspNetCore.Mvc.Testing;
+using Microsoft.Extensions.Configuration;
+using MongoDB.Bson;
+using MongoDB.Driver;
+using StellaOps.Excititor.Storage.Mongo;
+using StellaOps.Excititor.WebService.Contracts;
+using Xunit;
+
+namespace StellaOps.Excititor.WebService.Tests;
+
+public sealed class VexLinksetListEndpointTests : IDisposable
+{
+    private readonly IMongoRunner _runner;
+    private readonly TestWebApplicationFactory _factory;
+
+    public VexLinksetListEndpointTests()
+    {
+        _runner = MongoRunner.Run(new MongoRunnerOptions { UseSingleNodeReplicaSet = true });
+
+        _factory = new TestWebApplicationFactory(
+            configureConfiguration: configuration =>
+            {
+                configuration.AddInMemoryCollection(new Dictionary<string, string?>
+                {
+                    ["Excititor:Storage:Mongo:ConnectionString"] = _runner.ConnectionString,
+                    ["Excititor:Storage:Mongo:DatabaseName"] = "linksets_tests",
+                    ["Excititor:Storage:Mongo:DefaultTenant"] = "tests",
+                });
+            },
+            configureServices: services =>
+            {
+                TestServiceOverrides.Apply(services);
+                services.AddTestAuthentication();
+            });
+
+        SeedObservations();
+    }
+
+    [Fact]
+    public async void LinksetsEndpoint_GroupsByVulnAndProduct()
+    {
+        using var client = _factory.CreateClient(new WebApplicationFactoryClientOptions { AllowAutoRedirect = false });
+        client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", "vex.read");
+        client.DefaultRequestHeaders.Add("X-Stella-Tenant", "tests");
+
+        var response = await client.GetAsync("/v1/vex/linksets?vulnerabilityId=CVE-2025-0001&productKey=pkg:demo/app");
+        response.EnsureSuccessStatusCode();
+
+        var payload = await response.Content.ReadFromJsonAsync<VexLinksetListResponse>();
+        Assert.NotNull(payload);
+        Assert.Single(payload!.Items);
+
+        var item = payload.Items.Single();
+        Assert.Equal("CVE-2025-0001:pkg:demo/app", item.LinksetId);
+        Assert.Equal("CVE-2025-0001", item.VulnerabilityId);
+        Assert.Equal("pkg:demo/app", item.ProductKey);
+
+        item.Providers.Should().BeEquivalentTo(new[] { "provider-a", "provider-b" });
+        item.Statuses.Should().BeEquivalentTo(new[] { "affected", "fixed" });
+        item.Observations.Should().HaveCount(2);
+        item.Observations.Should().Contain(o => o.ProviderId == "provider-a" && o.Status == "affected");
+        item.Observations.Should().Contain(o => o.ProviderId == "provider-b" && o.Status == "fixed");
+    }
+
+    private void SeedObservations()
+    {
+        var client = new MongoClient(_runner.ConnectionString);
+        var database = client.GetDatabase("linksets_tests");
+        var collection = database.GetCollection<BsonDocument>(VexMongoCollectionNames.Observations);
+
+        var observations = new List<BsonDocument>
+        {
+            new()
+            {
+                { "_id", "obs-1" },
+                { "Tenant", "tests" },
+                { "ObservationId", "obs-1" },
+                { "VulnerabilityId", "cve-2025-0001" },
+                { "ProductKey", "pkg:demo/app" },
+                { "ProviderId", "provider-a" },
+                { "Status", "affected" },
+                { "StreamId", "stream" },
+                { "CreatedAt", DateTime.UtcNow },
+                { "Document", new BsonDocument { { "Digest", "digest-1" }, { "Format", "csaf" }, { "SourceUri", "https://example.test/a.json" } } },
+                { "Statements", new BsonArray
+                    {
+                        new BsonDocument
+                        {
+                            { "VulnerabilityId", "cve-2025-0001" },
+                            { "ProductKey", "pkg:demo/app" },
+                            { "Status", "affected" },
+                            { "LastObserved", DateTime.UtcNow },
+                            { "Purl", "pkg:demo/app" }
+                        }
+                    }
+                },
+                { "Linkset", new BsonDocument { { "Purls", new BsonArray { "pkg:demo/app" } } } }
+            },
+            new()
+            {
+                { "_id", "obs-2" },
+                { "Tenant", "tests" },
+                { "ObservationId", "obs-2" },
+                { "VulnerabilityId", "cve-2025-0001" },
+                { "ProductKey", "pkg:demo/app" },
+                { "ProviderId", "provider-b" },
+                { "Status", "fixed" },
+                { "StreamId", "stream" },
+                { "CreatedAt", DateTime.UtcNow.AddMinutes(1) },
+                { "Document", new BsonDocument { { "Digest", "digest-2" }, { "Format", "csaf" }, { "SourceUri", "https://example.test/b.json" } } },
+                { "Statements", new BsonArray
+                    {
+                        new BsonDocument
+                        {
+                            { "VulnerabilityId", "cve-2025-0001" },
+                            { "ProductKey", "pkg:demo/app" },
+                            { "Status", "fixed" },
+                            { "LastObserved", DateTime.UtcNow },
+                            { "Purl", "pkg:demo/app" }
+                        }
+                    }
+                },
+                { "Linkset", new BsonDocument { { "Purls", new BsonArray { "pkg:demo/app" } } } }
+            }
+        };
+
+        collection.InsertMany(observations);
+    }
+
+    public void Dispose()
+    {
+        _factory.Dispose();
+        _runner.Dispose();
+    }
+}