semi implemented and features implemented save checkpoint

src/Attestor/__Tests/StellaOps.Attestor.Infrastructure.Tests/HttpRekorClientTests.cs

@@ -16,6 +16,7 @@ using Org.BouncyCastle.Crypto.Signers;
 using Org.BouncyCastle.Math;
 using Org.BouncyCastle.X509;
 using StellaOps.Attestor.Core.Rekor;
+using StellaOps.Attestor.Core.Submission;
 using StellaOps.Attestor.Core.Verification;
 using StellaOps.Attestor.Infrastructure.Rekor;
 using StellaOps.TestKit;
@@ -25,6 +26,40 @@ namespace StellaOps.Attestor.Infrastructure.Tests;
 
 public sealed class HttpRekorClientTests
 {
+    [Trait("Category", TestCategories.Unit)]
+    [Fact]
+    public async Task SubmitAsync_HashPrecheckHit_ReusesExistingEntryWithoutNewSubmission()
+    {
+        var handler = new HashPrecheckHitHandler();
+        var client = CreateClient(handler);
+        var backend = CreateBackend();
+
+        var response = await client.SubmitAsync(CreateSubmissionRequest(), backend, CancellationToken.None);
+
+        response.Uuid.Should().Be("11111111-1111-1111-1111-111111111111");
+        response.Index.Should().Be(777);
+        response.Status.Should().Be("included");
+        handler.SubmitCalls.Should().Be(0);
+        handler.IndexLookupCalls.Should().BeGreaterThan(0);
+    }
+
+    [Trait("Category", TestCategories.Unit)]
+    [Fact]
+    public async Task SubmitAsync_HashPrecheckUnsupported_FallsBackToSubmission()
+    {
+        var handler = new HashPrecheckUnsupportedHandler();
+        var client = CreateClient(handler);
+        var backend = CreateBackend();
+
+        var response = await client.SubmitAsync(CreateSubmissionRequest(), backend, CancellationToken.None);
+
+        response.Uuid.Should().Be("new-uuid");
+        response.Index.Should().Be(42);
+        response.Status.Should().Be("included");
+        handler.SubmitCalls.Should().Be(1);
+        handler.IndexLookupCalls.Should().BeGreaterThan(0);
+    }
+
     [Trait("Category", TestCategories.Unit)]
     [Fact]
     public async Task VerifyInclusionAsync_MissingLogIndex_ReturnsFailure()
@@ -201,6 +236,40 @@ public sealed class HttpRekorClientTests
         return new HttpRekorClient(httpClient, NullLogger<HttpRekorClient>.Instance);
     }
 
+    private static AttestorSubmissionRequest CreateSubmissionRequest()
+    {
+        return new AttestorSubmissionRequest
+        {
+            Bundle = new AttestorSubmissionRequest.SubmissionBundle
+            {
+                Dsse = new AttestorSubmissionRequest.DsseEnvelope
+                {
+                    PayloadType = "application/vnd.in-toto+json",
+                    PayloadBase64 = Convert.ToBase64String(Encoding.UTF8.GetBytes("{}")),
+                    Signatures =
+                    {
+                        new AttestorSubmissionRequest.DsseSignature
+                        {
+                            KeyId = "test-key",
+                            Signature = "sig"
+                        }
+                    }
+                }
+            },
+            Meta = new AttestorSubmissionRequest.SubmissionMeta
+            {
+                BundleSha256 = new string('a', 64),
+                Artifact = new AttestorSubmissionRequest.ArtifactInfo
+                {
+                    Sha256 = new string('b', 64),
+                    Kind = "sbom"
+                },
+                LogPreference = "primary",
+                Archive = false
+            }
+        };
+    }
+
     private static RekorBackend CreateBackend()
     {
         return new RekorBackend
@@ -308,6 +377,63 @@ public sealed class HttpRekorClientTests
         }
     }
 
+    private sealed class HashPrecheckHitHandler : HttpMessageHandler
+    {
+        public int IndexLookupCalls { get; private set; }
+        public int SubmitCalls { get; private set; }
+
+        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            var path = request.RequestUri?.AbsolutePath ?? string.Empty;
+
+            if (request.Method == HttpMethod.Post && path.EndsWith("/api/v2/index/retrieve", StringComparison.Ordinal))
+            {
+                IndexLookupCalls++;
+                return Task.FromResult(BuildResponse("""["11111111-1111-1111-1111-111111111111"]"""));
+            }
+
+            if (request.Method == HttpMethod.Get && path.EndsWith("/api/v2/log/entries/11111111-1111-1111-1111-111111111111", StringComparison.Ordinal))
+            {
+                return Task.FromResult(BuildResponse("""{"uuid":"11111111-1111-1111-1111-111111111111","logIndex":777,"status":"included","integratedTime":1735689600}"""));
+            }
+
+            if (request.Method == HttpMethod.Post && path.EndsWith("/api/v2/log/entries", StringComparison.Ordinal))
+            {
+                SubmitCalls++;
+                return Task.FromResult(BuildResponse("""{"uuid":"should-not-submit","index":1,"status":"included"}"""));
+            }
+
+            return Task.FromResult(new HttpResponseMessage(HttpStatusCode.NotFound));
+        }
+    }
+
+    private sealed class HashPrecheckUnsupportedHandler : HttpMessageHandler
+    {
+        public int IndexLookupCalls { get; private set; }
+        public int SubmitCalls { get; private set; }
+
+        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            var path = request.RequestUri?.AbsolutePath ?? string.Empty;
+
+            if (request.Method == HttpMethod.Post &&
+                (path.EndsWith("/api/v2/index/retrieve", StringComparison.Ordinal) ||
+                 path.EndsWith("/api/v1/index/retrieve", StringComparison.Ordinal)))
+            {
+                IndexLookupCalls++;
+                return Task.FromResult(new HttpResponseMessage(HttpStatusCode.NotFound));
+            }
+
+            if (request.Method == HttpMethod.Post && path.EndsWith("/api/v2/log/entries", StringComparison.Ordinal))
+            {
+                SubmitCalls++;
+                return Task.FromResult(BuildResponse("""{"uuid":"new-uuid","index":42,"status":"included","integratedTime":1735689600}"""));
+            }
+
+            return Task.FromResult(new HttpResponseMessage(HttpStatusCode.NotFound));
+        }
+    }
+
     private sealed class ProofOnlyHandler : HttpMessageHandler
     {
         private readonly string _proofJson;

src/Attestor/__Tests/StellaOps.Attestor.Infrastructure.Tests/TASKS.md

@@ -12,3 +12,4 @@ Source of truth: `docs-archived/implplan/2025-12-29-csproj-audit/SPRINT_20251229
 | VAL-SMOKE-001 | DONE | Removed xUnit v2 references and verified unit tests pass. |
 | AUDIT-0208-T | DONE | Revalidated 2026-01-08 (raw string + xUnit1051 fixes). |
 | AUDIT-0208-A | DONE | Applied fixes 2026-01-08 (raw string + xUnit1051 fixes). |
+| SPRINT-20260208-060-IDEMP-001 | DONE | Added deterministic unit coverage for Rekor hash pre-check and submission fallback behavior; `HttpRekorClientTests` passing (2026-02-08). |