feat(acl): resolve zaaktype + informatieobjecttype by business key, not a pinned URL (refs #113)

The ACL now discovers its BIG zaaktype (by identificatie) and diploma
informatieobjecttype (by omschrijving) from OpenZaak's Catalogi API, instead of
being handed server-assigned URLs in config. A CachedZaaktypeCatalog resolves
lazily on first use and caches (success only, so a pre-publish miss is retried);
AclDefaults now carries ZaaktypeIdentificatie/InformatieobjecttypeOmschrijving.
Clear errors replace the opaque placeholder-URL 400. Unit tests cover the
resolver (resolve/cache/retry-on-failure) and the gateway lookups (match/miss).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

services/acl/Acl.Tests/AclServiceTests.cs

@@ -6,6 +6,12 @@ public class AclServiceTests
 {
     private sealed class FakeGateway : IZaakGateway
     {
+        // The URLs the catalogus resolves the configured identificatie/omschrijving to (S-27).
+        public Uri ResolvedZaaktype { get; } = new("http://openzaak/catalogi/api/v1/zaaktypen/big");
+        public Uri ResolvedInformatieobjecttype { get; } = new("http://openzaak/catalogi/api/v1/informatieobjecttypen/dip");
+        public string? ResolvedByIdentificatie;
+        public string? ResolvedByOmschrijving;
+
         public ZaakRequest? Captured;
         public Uri Result { get; } = new("http://openzaak/zaken/api/v1/zaken/abc");
 
@@ -47,6 +53,18 @@ public class AclServiceTests
             StoredDocument = request;
             return Task.FromResult(DocumentResult);
         }
+
+        public Task<Uri> ResolveZaaktypeUrlAsync(string identificatie, CancellationToken ct = default)
+        {
+            ResolvedByIdentificatie = identificatie;
+            return Task.FromResult(ResolvedZaaktype);
+        }
+
+        public Task<Uri> ResolveInformatieobjecttypeUrlAsync(string omschrijving, CancellationToken ct = default)
+        {
+            ResolvedByOmschrijving = omschrijving;
+            return Task.FromResult(ResolvedInformatieobjecttype);
+        }
     }
 
     private static AclDefaults Defaults() => new()
@@ -54,28 +72,23 @@ public class AclServiceTests
         Bronorganisatie = "517439943",
         VerantwoordelijkeOrganisatie = "517439943",
         Vertrouwelijkheidaanduiding = "openbaar",
-        ZaaktypeUrl = new("http://openzaak/catalogi/api/v1/zaaktypen/big"),
-        InformatieobjecttypeUrl = new("http://openzaak/catalogi/api/v1/informatieobjecttypen/dip"),
+        ZaaktypeIdentificatie = "BIG-REGISTRATIE",
+        InformatieobjecttypeOmschrijving = "Diploma",
     };
 
+    private static AclService ServiceWith(FakeGateway gateway, AclDefaults defaults, DateOnly today) =>
+        new(gateway, defaults, new CachedZaaktypeCatalog(gateway, defaults), new FixedClock(today));
+
     private sealed class FixedClock(DateOnly today) : IClock
     {
         public DateOnly Today { get; } = today;
     }
 
     [Fact]
-    public async Task Opening_a_zaak_default_fills_zgw_fields_and_returns_the_zaak_url()
+    public async Task Opening_a_zaak_default_fills_zgw_fields_and_uses_the_resolved_zaaktype()
     {
         var gateway = new FakeGateway();
-        var defaults = new AclDefaults
-        {
-            Bronorganisatie = "517439943",
-            VerantwoordelijkeOrganisatie = "517439943",
-            Vertrouwelijkheidaanduiding = "openbaar",
-            ZaaktypeUrl = new("http://openzaak/catalogi/api/v1/zaaktypen/big"),
-            InformatieobjecttypeUrl = new("http://openzaak/catalogi/api/v1/informatieobjecttypen/dip"),
-        };
-        var service = new AclService(gateway, defaults, new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
 
         var url = await service.OpenZaakAsync(new DomainRegistration("123456782", "reg-77"));
 
@@ -84,7 +97,9 @@ public class AclServiceTests
         Assert.Equal("517439943", req.Bronorganisatie);
         Assert.Equal("517439943", req.VerantwoordelijkeOrganisatie);
         Assert.Equal("openbaar", req.Vertrouwelijkheidaanduiding);
-        Assert.Equal(defaults.ZaaktypeUrl, req.Zaaktype);
+        // The zaaktype is resolved from the configured identificatie, not a pinned URL (S-27).
+        Assert.Equal("BIG-REGISTRATIE", gateway.ResolvedByIdentificatie);
+        Assert.Equal(gateway.ResolvedZaaktype, req.Zaaktype);
         Assert.Equal(new DateOnly(2026, 6, 4), req.Startdatum);
         // The registration reference becomes the zaak identificatie (#78).
         Assert.Equal("reg-77", req.Identificatie);
@@ -94,33 +109,24 @@ public class AclServiceTests
     public async Task Rejects_a_null_registration_without_calling_the_gateway()
     {
         var gateway = new FakeGateway();
-        var defaults = new AclDefaults
-        {
-            Bronorganisatie = "517439943",
-            VerantwoordelijkeOrganisatie = "517439943",
-            Vertrouwelijkheidaanduiding = "openbaar",
-            ZaaktypeUrl = new("http://openzaak/catalogi/api/v1/zaaktypen/big"),
-            InformatieobjecttypeUrl = new("http://openzaak/catalogi/api/v1/informatieobjecttypen/dip"),
-        };
-        var service = new AclService(gateway, defaults, new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
 
         await Assert.ThrowsAsync<ArgumentNullException>(() => service.OpenZaakAsync(null!));
         Assert.Null(gateway.Captured);
     }
 
     [Fact]
-    public async Task Approving_a_zaak_sets_it_to_its_zaaktypes_eindstatus_dated_today()
+    public async Task Approving_a_zaak_sets_it_to_its_resolved_zaaktypes_eindstatus_dated_today()
     {
         var gateway = new FakeGateway();
-        var defaults = Defaults();
-        var service = new AclService(gateway, defaults, new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
         var zaak = new Uri("http://openzaak/zaken/api/v1/zaken/abc");
 
         await service.ApproveZaakAsync(zaak);
 
         Assert.NotNull(gateway.Approved);
         Assert.Equal(zaak, gateway.Approved!.Value.Zaak);
-        Assert.Equal(defaults.ZaaktypeUrl, gateway.Approved.Value.Zaaktype);
+        Assert.Equal(gateway.ResolvedZaaktype, gateway.Approved.Value.Zaaktype);
         Assert.Equal(new DateOnly(2026, 6, 4), gateway.Approved.Value.Datum);
     }
 
@@ -128,7 +134,7 @@ public class AclServiceTests
     public async Task Approving_a_null_zaak_is_rejected_without_touching_the_gateway()
     {
         var gateway = new FakeGateway();
-        var service = new AclService(gateway, Defaults(), new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
 
         await Assert.ThrowsAsync<ArgumentNullException>(() => service.ApproveZaakAsync(null!));
         Assert.Null(gateway.Approved);
@@ -138,15 +144,14 @@ public class AclServiceTests
     public async Task Cancelling_a_zaak_sets_it_to_the_cancellation_status_dated_today()
     {
         var gateway = new FakeGateway();
-        var defaults = Defaults();
-        var service = new AclService(gateway, defaults, new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
         var zaak = new Uri("http://openzaak/zaken/api/v1/zaken/abc");
 
         await service.CancelZaakAsync(zaak);
 
         Assert.NotNull(gateway.Cancelled);
         Assert.Equal(zaak, gateway.Cancelled!.Value.Zaak);
-        Assert.Equal(defaults.ZaaktypeUrl, gateway.Cancelled.Value.Zaaktype);
+        Assert.Equal(gateway.ResolvedZaaktype, gateway.Cancelled.Value.Zaaktype);
         Assert.Equal(new DateOnly(2026, 6, 4), gateway.Cancelled.Value.Datum);
         // Cancellation must not touch the approval path.
         Assert.Null(gateway.Approved);
@@ -156,18 +161,17 @@ public class AclServiceTests
     public async Task Cancelling_a_null_zaak_is_rejected_without_touching_the_gateway()
     {
         var gateway = new FakeGateway();
-        var service = new AclService(gateway, Defaults(), new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
 
         await Assert.ThrowsAsync<ArgumentNullException>(() => service.CancelZaakAsync(null!));
         Assert.Null(gateway.Cancelled);
     }
 
     [Fact]
-    public async Task Storing_a_diploma_default_fills_the_document_fields_and_returns_its_url()
+    public async Task Storing_a_diploma_default_fills_the_document_fields_and_uses_the_resolved_informatieobjecttype()
     {
         var gateway = new FakeGateway();
-        var defaults = Defaults();
-        var service = new AclService(gateway, defaults, new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
         var zaak = new Uri("http://openzaak/zaken/api/v1/zaken/abc");
 
         var url = await service.StoreDiplomaAsync(zaak, [1, 2, 3], "diploma.pdf", "application/pdf");
@@ -175,7 +179,9 @@ public class AclServiceTests
         Assert.Equal(gateway.DocumentResult, url);
         var req = gateway.StoredDocument!;
         Assert.Equal(zaak, req.Zaak);
-        Assert.Equal(defaults.InformatieobjecttypeUrl, req.Informatieobjecttype);
+        // The informatieobjecttype is resolved from the configured omschrijving (S-27).
+        Assert.Equal("Diploma", gateway.ResolvedByOmschrijving);
+        Assert.Equal(gateway.ResolvedInformatieobjecttype, req.Informatieobjecttype);
         Assert.Equal("517439943", req.Bronorganisatie);
         Assert.Equal("openbaar", req.Vertrouwelijkheidaanduiding);
         Assert.Equal(new DateOnly(2026, 6, 4), req.Creatiedatum);
@@ -188,7 +194,7 @@ public class AclServiceTests
     [Fact]
     public async Task Storing_a_diploma_rejects_null_or_blank_arguments()
     {
-        var service = new AclService(new FakeGateway(), Defaults(), new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(new FakeGateway(), Defaults(), new DateOnly(2026, 6, 4));
         var zaak = new Uri("http://openzaak/zaken/api/v1/zaken/abc");
 
         await Assert.ThrowsAsync<ArgumentNullException>(() => service.StoreDiplomaAsync(null!, [1], "d.pdf", "application/pdf"));
@@ -201,7 +207,7 @@ public class AclServiceTests
     public async Task Reading_a_zaak_reference_returns_the_zaaks_identificatie()
     {
         var gateway = new FakeGateway();
-        var service = new AclService(gateway, Defaults(), new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
         var zaak = new Uri("http://openzaak/zaken/api/v1/zaken/abc");
 
         var reference = await service.GetZaakReferenceAsync(zaak);
@@ -214,7 +220,7 @@ public class AclServiceTests
     public async Task Reading_a_null_zaak_reference_is_rejected()
     {
         var gateway = new FakeGateway();
-        var service = new AclService(gateway, Defaults(), new FixedClock(new DateOnly(2026, 6, 4)));
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
 
         await Assert.ThrowsAsync<ArgumentNullException>(() => service.GetZaakReferenceAsync(null!));
         Assert.Null(gateway.ReadReferenceFor);

services/acl/Acl.Tests/OpenZaakGatewayTests.cs

@@ -675,4 +675,92 @@ public class OpenZaakGatewayTests
 
         await Assert.ThrowsAsync<ArgumentNullException>(() => Gateway(handler).StoreDocumentAsync(null!));
     }
+
+    // ── Catalogi resolution by business key (S-27) ────────────────────────────────────────────────
+
+    [Fact]
+    public async Task Resolves_the_published_zaaktype_url_by_identificatie()
+    {
+        HttpRequestMessage? seen = null;
+        var handler = new StubHandler(req =>
+        {
+            seen = req;
+            return Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = JsonContent.Create(new
+                {
+                    results = new[] { new { url = "http://openzaak/catalogi/api/v1/zaaktypen/big", identificatie = "BIG-REGISTRATIE" } },
+                }),
+            });
+        });
+
+        var url = await Gateway(handler).ResolveZaaktypeUrlAsync("BIG-REGISTRATIE");
+
+        Assert.Equal("http://openzaak/catalogi/api/v1/zaaktypen/big", url.ToString());
+        Assert.Equal(HttpMethod.Get, seen!.Method);
+        // Filters to the published zaaktype with that identificatie, and authenticates.
+        Assert.Contains("/catalogi/api/v1/zaaktypen", seen.RequestUri!.ToString());
+        Assert.Contains("status=definitief", seen.RequestUri!.Query);
+        Assert.Contains("identificatie=BIG-REGISTRATIE", seen.RequestUri!.Query);
+        Assert.Equal("Bearer", seen.Headers.Authorization!.Scheme);
+    }
+
+    [Fact]
+    public async Task Resolving_a_zaaktype_throws_a_clear_error_when_none_is_published()
+    {
+        var handler = new StubHandler(_ => Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
+        {
+            Content = JsonContent.Create(new { results = Array.Empty<object>() }),
+        }));
+
+        var ex = await Assert.ThrowsAsync<InvalidOperationException>(
+            () => Gateway(handler).ResolveZaaktypeUrlAsync("BIG-REGISTRATIE"));
+        Assert.Contains("BIG-REGISTRATIE", ex.Message);
+    }
+
+    [Fact]
+    public async Task Resolves_the_informatieobjecttype_url_by_omschrijving()
+    {
+        var handler = new StubHandler(_ => Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
+        {
+            Content = JsonContent.Create(new
+            {
+                results = new[]
+                {
+                    new { url = "http://openzaak/catalogi/api/v1/informatieobjecttypen/other", omschrijving = "Overig" },
+                    new { url = "http://openzaak/catalogi/api/v1/informatieobjecttypen/dip", omschrijving = "Diploma" },
+                },
+            }),
+        }));
+
+        var url = await Gateway(handler).ResolveInformatieobjecttypeUrlAsync("Diploma");
+
+        // Matches on omschrijving, not position.
+        Assert.Equal("http://openzaak/catalogi/api/v1/informatieobjecttypen/dip", url.ToString());
+    }
+
+    [Fact]
+    public async Task Resolving_an_informatieobjecttype_throws_when_no_omschrijving_matches()
+    {
+        var handler = new StubHandler(_ => Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
+        {
+            Content = JsonContent.Create(new
+            {
+                results = new[] { new { url = "http://openzaak/catalogi/api/v1/informatieobjecttypen/other", omschrijving = "Overig" } },
+            }),
+        }));
+
+        var ex = await Assert.ThrowsAsync<InvalidOperationException>(
+            () => Gateway(handler).ResolveInformatieobjecttypeUrlAsync("Diploma"));
+        Assert.Contains("Diploma", ex.Message);
+    }
+
+    [Fact]
+    public async Task Resolving_rejects_a_blank_business_key_without_calling_openzaak()
+    {
+        var handler = new StubHandler(_ => throw new InvalidOperationException("should not be sent"));
+
+        await Assert.ThrowsAnyAsync<ArgumentException>(() => Gateway(handler).ResolveZaaktypeUrlAsync(" "));
+        await Assert.ThrowsAnyAsync<ArgumentException>(() => Gateway(handler).ResolveInformatieobjecttypeUrlAsync(" "));
+    }
 }

services/acl/Acl.Tests/ZaaktypeCatalogTests.cs

@@ -0,0 +1,92 @@
+using Acl.Application;
+
+namespace Acl.Tests;
+
+public class ZaaktypeCatalogTests
+{
+    // A gateway that only supports resolution; the other members are unused here.
+    private sealed class ResolvingGateway : IZaakGateway
+    {
+        public int ZaaktypeCalls;
+        public int InformatieobjecttypeCalls;
+        public string? LastIdentificatie;
+        public string? LastOmschrijving;
+        public int ThrowZaaktypeTimes;
+        public Uri ZaaktypeUrl { get; } = new("http://openzaak/catalogi/api/v1/zaaktypen/big");
+        public Uri InformatieobjecttypeUrl { get; } = new("http://openzaak/catalogi/api/v1/informatieobjecttypen/dip");
+
+        public Task<Uri> ResolveZaaktypeUrlAsync(string identificatie, CancellationToken ct = default)
+        {
+            ZaaktypeCalls++;
+            LastIdentificatie = identificatie;
+            if (ZaaktypeCalls <= ThrowZaaktypeTimes)
+                throw new InvalidOperationException("no published zaaktype yet");
+            return Task.FromResult(ZaaktypeUrl);
+        }
+
+        public Task<Uri> ResolveInformatieobjecttypeUrlAsync(string omschrijving, CancellationToken ct = default)
+        {
+            InformatieobjecttypeCalls++;
+            LastOmschrijving = omschrijving;
+            return Task.FromResult(InformatieobjecttypeUrl);
+        }
+
+        public Task<Uri> OpenZaakAsync(ZaakRequest request, CancellationToken ct = default) => throw new NotSupportedException();
+        public Task SetZaakToEindstatusAsync(Uri z, Uri zt, DateOnly d, CancellationToken ct = default) => throw new NotSupportedException();
+        public Task SetZaakToCancellationStatusAsync(Uri z, Uri zt, DateOnly d, CancellationToken ct = default) => throw new NotSupportedException();
+        public Task<string> GetZaakIdentificatieAsync(Uri z, CancellationToken ct = default) => throw new NotSupportedException();
+        public Task<Uri> StoreDocumentAsync(DocumentRequest r, CancellationToken ct = default) => throw new NotSupportedException();
+    }
+
+    private static AclDefaults Defaults() => new()
+    {
+        Bronorganisatie = "517439943",
+        VerantwoordelijkeOrganisatie = "517439943",
+        Vertrouwelijkheidaanduiding = "openbaar",
+        ZaaktypeIdentificatie = "BIG-REGISTRATIE",
+        InformatieobjecttypeOmschrijving = "Diploma",
+    };
+
+    [Fact]
+    public async Task Resolves_the_zaaktype_and_informatieobjecttype_by_their_configured_business_keys()
+    {
+        var gateway = new ResolvingGateway();
+        var catalog = new CachedZaaktypeCatalog(gateway, Defaults());
+
+        Assert.Equal(gateway.ZaaktypeUrl, await catalog.GetZaaktypeUrlAsync());
+        Assert.Equal(gateway.InformatieobjecttypeUrl, await catalog.GetInformatieobjecttypeUrlAsync());
+        Assert.Equal("BIG-REGISTRATIE", gateway.LastIdentificatie);
+        Assert.Equal("Diploma", gateway.LastOmschrijving);
+    }
+
+    [Fact]
+    public async Task Caches_the_resolved_urls_so_the_gateway_is_hit_once()
+    {
+        var gateway = new ResolvingGateway();
+        var catalog = new CachedZaaktypeCatalog(gateway, Defaults());
+
+        for (var i = 0; i < 3; i++)
+        {
+            await catalog.GetZaaktypeUrlAsync();
+            await catalog.GetInformatieobjecttypeUrlAsync();
+        }
+
+        Assert.Equal(1, gateway.ZaaktypeCalls);
+        Assert.Equal(1, gateway.InformatieobjecttypeCalls);
+    }
+
+    [Fact]
+    public async Task Does_not_cache_a_failed_resolution_so_it_is_retried()
+    {
+        // The zaaktype is not published yet on the first call; the catalog must retry (not cache the
+        // failure) so a later call succeeds once it is published.
+        var gateway = new ResolvingGateway { ThrowZaaktypeTimes = 1 };
+        var catalog = new CachedZaaktypeCatalog(gateway, Defaults());
+
+        await Assert.ThrowsAsync<InvalidOperationException>(() => catalog.GetZaaktypeUrlAsync());
+        var url = await catalog.GetZaaktypeUrlAsync();
+
+        Assert.Equal(gateway.ZaaktypeUrl, url);
+        Assert.Equal(2, gateway.ZaaktypeCalls);
+    }
+}