Return the reason why the relationship cannot be created from CanCrea…

…teRelationship (#903)

* refactor: simplify usage of test container in MigrationReaderTests

* feat: return code

* test: add/update integration tests

* chore: remove unused ApplicationErrors

* feat: don't mention "relationshipRequest" in error codes

* test: minor changes

* test: inherit from AbstractTestsBase

Applications/ConsumerApi/test/ConsumerApi.Tests.Integration/Features/Relationships/CanCreate/GET.feature

@@ -6,20 +6,23 @@ Feature: GET /Relationships/CanCreate
         When i1 sends a GET request to the /Relationships/CanCreate?peer={id} endpoint with id=i2.id
         Then the response status code is 200 (OK)
         And a Relationship can be established
+        And the response does not contain a relationship creation check code
 
     Scenario: Two identities with an active Relationship can't create another one
         Given Identities i1 and i2
         And an active Relationship r between i1 and i2
         When i1 sends a GET request to the /Relationships/CanCreate?peer={id} endpoint with id=i2.id
         Then the response status code is 200 (OK)
         And a Relationship can not be established
+        And the relationship creation check code is "error.platform.validation.relationship.relationshipToTargetAlreadyExists"
 
     Scenario: Two identities with a rejected Relationship can create one
         Given Identities i1 and i2
         And a rejected Relationship r between i1 and i2
         When i1 sends a GET request to the /Relationships/CanCreate?peer={id} endpoint with id=i2.id
         Then the response status code is 200 (OK)
         And a Relationship can be established
+        And the response does not contain a relationship creation check code
 
     Scenario: Two identities with a rejected and an active Relationship can't create one
         Given Identities i1 and i2
@@ -28,6 +31,7 @@ Feature: GET /Relationships/CanCreate
         When i1 sends a GET request to the /Relationships/CanCreate?peer={id} endpoint with id=i2.id
         Then the response status code is 200 (OK)
         And a Relationship can not be established
+        And the relationship creation check code is "error.platform.validation.relationship.relationshipToTargetAlreadyExists"
 
     Scenario: Two identities with two rejected Relationships can create one
         Given Identities i1 and i2
@@ -36,10 +40,12 @@ Feature: GET /Relationships/CanCreate
         When i1 sends a GET request to the /Relationships/CanCreate?peer={id} endpoint with id=i2.id
         Then the response status code is 200 (OK)
         And a Relationship can be established
+        And the response does not contain a relationship creation check code
 
     Scenario: Cannot create Relationship if peer is to be deleted
         Given Identities i1 and i2
         And i2 is in status "ToBeDeleted"
         When i1 sends a GET request to the /Relationships/CanCreate?peer={id} endpoint with id=i2.id
         Then the response status code is 200 (OK)
         And a Relationship can not be established
+        And the relationship creation check code is "error.platform.validation.relationship.peerIsToBeDeleted"

Applications/ConsumerApi/test/ConsumerApi.Tests.Integration/StepDefinitions/RelationshipsStepDefinitions.cs

@@ -188,15 +188,25 @@ public async Task WhenAGetRequestIsSentToTheCanCreateEndpointByIdentityForIdenti
     [Then("a Relationship can be established")]
     public void ThenARelationshipCanBeEstablished()
     {
-        if (_canEstablishRelationshipResponse != null)
-            _canEstablishRelationshipResponse.Result!.CanCreate.Should().BeTrue();
+        _canEstablishRelationshipResponse!.Result!.CanCreate.Should().BeTrue();
     }
 
     [Then("a Relationship can not be established")]
     public void ThenARelationshipCanNotBeEstablished()
     {
-        if (_canEstablishRelationshipResponse != null)
-            _canEstablishRelationshipResponse.Result!.CanCreate.Should().BeFalse();
+        _canEstablishRelationshipResponse!.Result!.CanCreate.Should().BeFalse();
+    }
+
+    [Then(@"the relationship creation check code is ""(.+)""")]
+    public void ThenTheCodeIs(string code)
+    {
+        _canEstablishRelationshipResponse!.Result!.Code.Should().Be(code);
+    }
+
+    [Then(@"the response does not contain a relationship creation check code")]
+    public void ThenThereIsNoCode()
+    {
+        _canEstablishRelationshipResponse!.Result!.Code.Should().BeNull();
     }
 
     #endregion

Applications/DatabaseMigrator/test/DatabaseMigrator.Tests/MigrationReaderTests.cs

@@ -48,12 +48,12 @@ public async Task Returns_migrations_in_correct_order()
 
     private static async Task<MigrationReader> CreateMigrationReader()
     {
-        await StartPostgres("postgres", "admin", 5444);
+        var dbConnectionString = await StartPostgres();
 
         var services = new ServiceCollection();
 
         services.AddSingleton<IEventBus, DummyEventBus>();
-        services.AddAllDbContexts(new SqlDatabaseConfiguration { Provider = "Postgres", ConnectionString = "User ID=postgres;Password=admin;Server=localhost;Port=5444;Database=enmeshed;" });
+        services.AddAllDbContexts(new SqlDatabaseConfiguration { Provider = "Postgres", ConnectionString = dbConnectionString });
         services.AddSingleton<DbContextProvider>();
         services.AddSingleton<MigrationReader>();
 
@@ -62,15 +62,15 @@ private static async Task<MigrationReader> CreateMigrationReader()
         return migrationReader;
     }
 
-    private static async Task StartPostgres(string username, string password, int port)
+    private static async Task<string> StartPostgres()
     {
         var postgreSqlContainer = new PostgreSqlBuilder()
             .WithImage("postgres:16")
-            .WithUsername(username)
-            .WithPassword(password)
-            .WithPortBinding(port, 5432)
+            .WithDatabase("enmeshed")
             .Build();
 
         await postgreSqlContainer.StartAsync();
+
+        return postgreSqlContainer.GetConnectionString();
     }
 }

Modules/Messages/src/Messages.Infrastructure/Persistence/Database/QueryableExtensions/RelationshipsQueryableExtensions.cs

@@ -9,9 +9,4 @@ public static IQueryable<Relationship> WithParticipants(this IQueryable<Relation
     {
         return query.Where(r => r.From == participant1 && r.To == participant2 || r.From == participant2 && r.To == participant1);
     }
-
-    public static IQueryable<Relationship> Active(this IQueryable<Relationship> query)
-    {
-        return query.Where(r => r.Status == RelationshipStatus.Active);
-    }
 }

Modules/Messages/src/Messages.Infrastructure/Persistence/Database/Repository/RelationshipsRepository.cs

@@ -1,7 +1,6 @@
 using Backbone.DevelopmentKit.Identity.ValueObjects;
 using Backbone.Modules.Messages.Application.Infrastructure.Persistence.Repository;
 using Backbone.Modules.Messages.Domain.Entities;
-using Backbone.Modules.Messages.Domain.Ids;
 using Backbone.Modules.Messages.Infrastructure.Persistence.Database.QueryableExtensions;
 using Microsoft.EntityFrameworkCore;
 
@@ -16,14 +15,6 @@ public RelationshipsRepository(MessagesDbContext dbContext)
         _readOnlyRelationships = dbContext.Relationships.AsNoTracking();
     }
 
-    public Task<RelationshipId?> GetIdOfRelationshipBetweenSenderAndRecipient(IdentityAddress sender, IdentityAddress recipient)
-    {
-        return _readOnlyRelationships
-            .WithParticipants(sender, recipient)
-            .Select(r => r.Id)
-            .FirstOrDefaultAsync();
-    }
-
     public Task<Relationship?> FindYoungestRelationship(IdentityAddress sender, IdentityAddress recipient, CancellationToken cancellationToken)
     {
         return _readOnlyRelationships

Modules/Relationships/src/Relationships.Application/ApplicationErrors.cs

@@ -6,10 +6,10 @@ public static class ApplicationErrors
 {
     public static class Relationship
     {
-        public static ApplicationError PeerIsToBeDeleted(string peerToBeDeleted)
+        public static ApplicationError PeerIsToBeDeleted()
         {
             return new ApplicationError("error.platform.validation.relationship.peerIsToBeDeleted",
-                $"Cannot establish relationship with '{peerToBeDeleted}' because they are in status 'ToBeDeleted'.");
+                "Cannot establish relationship with the owner of the template because the owner is in status 'ToBeDeleted'.");
         }
     }
 }

Modules/Relationships/src/Relationships.Application/Relationships/Commands/CreateRelationship/Handler.cs

@@ -54,9 +54,7 @@ private async Task ReadTemplateFromDb()
     private async Task CreateAndSaveRelationship()
     {
         var existingRelationships = await _relationshipsRepository.FindRelationships(
-            r =>
-                (r.From == _activeIdentity && r.To == _template.CreatedBy) ||
-                (r.From == _template.CreatedBy && r.To == _activeIdentity),
+            Relationship.IsBetween(_activeIdentity, _template.CreatedBy),
             _cancellationToken
         );
 

Modules/Relationships/src/Relationships.Application/Relationships/Queries/CanEstablishRelationship/CanEstablishRelationshipResponse.cs

@@ -3,4 +3,5 @@
 public class CanEstablishRelationshipResponse
 {
     public required bool CanCreate { get; set; }
+    public required string? Code { get; set; }
 }

Modules/Relationships/src/Relationships.Application/Relationships/Queries/CanEstablishRelationship/Handler.cs

@@ -1,6 +1,6 @@
 using Backbone.BuildingBlocks.Application.Abstractions.Infrastructure.UserContext;
-using Backbone.DevelopmentKit.Identity.ValueObjects;
 using Backbone.Modules.Relationships.Application.Infrastructure.Persistence.Repository;
+using Backbone.Modules.Relationships.Domain.Aggregates.Relationships;
 using MediatR;
 
 namespace Backbone.Modules.Relationships.Application.Relationships.Queries.CanEstablishRelationship;
@@ -18,8 +18,13 @@ public Handler(IUserContext userContext, IRelationshipsRepository relationshipsR
 
     public async Task<CanEstablishRelationshipResponse> Handle(CanEstablishRelationshipQuery request, CancellationToken cancellationToken)
     {
-        var hasActiveRelationship = await _relationshipsRepository.RelationshipBetweenTwoIdentitiesExists(_userContext.GetAddress(), IdentityAddress.Parse(request.PeerAddress), cancellationToken);
+        var existingRelationships = await _relationshipsRepository.FindRelationships(
+            Relationship.IsBetween(request.PeerAddress, _userContext.GetAddress()),
+            cancellationToken
+        );
 
-        return new CanEstablishRelationshipResponse { CanCreate = !hasActiveRelationship };
+        var error = Relationship.CanEstablish(existingRelationships.ToList());
+
+        return new CanEstablishRelationshipResponse { CanCreate = error == null, Code = error?.Code };
     }
 }

Modules/Relationships/src/Relationships.ConsumerApi/Controllers/RelationshipsController.cs

@@ -203,7 +203,7 @@ public async Task<IActionResult> CanEstablishRelationship([FromQuery(Name = "pee
         var peerIdentity = await _mediator.Send(new GetIdentityQuery(peerAddress), cancellationToken);
 
         var response = peerIdentity.Status is IdentityStatus.ToBeDeleted
-            ? new CanEstablishRelationshipResponse { CanCreate = false }
+            ? new CanEstablishRelationshipResponse { CanCreate = false, Code = ApplicationErrors.Relationship.PeerIsToBeDeleted().Code }
             : await _mediator.Send(new CanEstablishRelationshipQuery { PeerAddress = peerAddress }, cancellationToken);
 
         return Ok(response);
@@ -213,7 +213,7 @@ private async Task EnsurePeerIsNotToBeDeleted(string peerIdentityAddress, Cancel
     {
         var peerIdentity = await _mediator.Send(new GetIdentityQuery(peerIdentityAddress), cancellationToken);
         if (peerIdentity.Status is IdentityStatus.ToBeDeleted)
-            throw new ApplicationException(ApplicationErrors.Relationship.PeerIsToBeDeleted(peerIdentity.Address));
+            throw new ApplicationException(ApplicationErrors.Relationship.PeerIsToBeDeleted());
     }
 }
 

Modules/Relationships/src/Relationships.Domain/Aggregates/Relationships/Relationship.CanEstablishTests.cs

@@ -0,0 +1,64 @@
+using Backbone.Modules.Relationships.Domain.TestHelpers;
+using Backbone.UnitTestTools.BaseClasses;
+using FluentAssertions;
+using Xunit;
+
+namespace Backbone.Modules.Relationships.Domain.Aggregates.Relationships;
+
+public class RelationshipCanEstablishTests : AbstractTestsBase
+{
+    [Fact]
+    public void Returns_null_when_no_relationships_exists()
+    {
+        // Act
+        var error = Relationship.CanEstablish([]);
+
+        // Assert
+        error.Should().BeNull();
+    }
+
+    [Fact]
+    public void Returns_null_when_a_relationship_ready_for_deletion_exists()
+    {
+        // Act
+        var error = Relationship.CanEstablish([TestData.CreateRelationshipInStatus(RelationshipStatus.ReadyForDeletion)]);
+
+        // Assert
+        error.Should().BeNull();
+    }
+
+    [Fact]
+    public void Returns_null_when_a_rejected_relationship_exists()
+    {
+        // Act
+        var error = Relationship.CanEstablish([TestData.CreateRelationshipInStatus(RelationshipStatus.Rejected)]);
+
+        // Assert
+        error.Should().BeNull();
+    }
+
+    [Fact]
+    public void Returns_null_when_a_revoked_relationship_exists()
+    {
+        // Act
+        var error = Relationship.CanEstablish([TestData.CreateRelationshipInStatus(RelationshipStatus.Revoked)]);
+
+        // Assert
+        error.Should().BeNull();
+    }
+
+    [Theory]
+    [InlineData(RelationshipStatus.Pending)]
+    [InlineData(RelationshipStatus.Active)]
+    [InlineData(RelationshipStatus.Terminated)]
+    [InlineData(RelationshipStatus.DeletionProposed)]
+    public void Returns_an_error_when_a_relationship_exists(RelationshipStatus status)
+    {
+        // Act
+        var error = Relationship.CanEstablish([TestData.CreateRelationshipInStatus(status)]);
+
+        // Assert
+        error.Should().NotBeNull();
+        error!.Code.Should().Be("error.platform.validation.relationship.relationshipToTargetAlreadyExists");
+    }
+}

Modules/Relationships/src/Relationships.Domain/Aggregates/Relationships/Relationship.CountAsActiveExpressionTests.cs → Modules/Relationships/src/Relationships.Domain/Aggregates/Relationships/Relationship.ExpressionTests.cs

@@ -1,7 +1,9 @@
-using Backbone.Modules.Relationships.Domain.TestHelpers;
+using Backbone.DevelopmentKit.Identity.ValueObjects;
+using Backbone.Modules.Relationships.Domain.TestHelpers;
 using Backbone.UnitTestTools.BaseClasses;
 using FluentAssertions;
 using Xunit;
+using static Backbone.UnitTestTools.Data.TestDataGenerator;
 
 namespace Backbone.Modules.Relationships.Domain.Aggregates.Relationships;
 
@@ -106,6 +108,49 @@ public void HasParticipant_recognizes_foreign_addresses()
 
     #endregion
 
+    #region IsBetween
+
+    [Fact]
+    public void IsBetween_returns_true_when_both_identities_are_part_of_relationship()
+    {
+        // Arrange
+        var participant1 = CreateRandomIdentityAddress();
+        var participant2 = CreateRandomIdentityAddress();
+        var relationship = TestData.CreateActiveRelationship(participant1, participant2);
+
+        // Act
+        var result1 = relationship.EvaluateIsBetween(participant1, participant2);
+        var result2 = relationship.EvaluateIsBetween(participant2, participant1);
+
+        // Assert
+        result1.Should().BeTrue();
+        result2.Should().BeTrue();
+    }
+
+    [Fact]
+    public void IsBetween_returns_false_when_at_least_one_identity_is_not_part_of_relationship()
+    {
+        // Arrange
+        var participant1 = CreateRandomIdentityAddress();
+        var participant2 = CreateRandomIdentityAddress();
+        var otherIdentity1 = CreateRandomIdentityAddress();
+        var otherIdentity2 = CreateRandomIdentityAddress();
+
+        var relationship = TestData.CreateActiveRelationship(participant1, participant2);
+
+        // Act
+        var result1 = relationship.EvaluateIsBetween(participant1, otherIdentity1);
+        var result2 = relationship.EvaluateIsBetween(participant2, otherIdentity1);
+        var result3 = relationship.EvaluateIsBetween(otherIdentity1, otherIdentity2);
+
+        // Assert
+        result1.Should().BeFalse();
+        result2.Should().BeFalse();
+        result3.Should().BeFalse();
+    }
+
+    #endregion
+
     #region HasStatusInWhichPeerShouldBeNotifiedAboutDeletion
 
     [Theory]
@@ -150,4 +195,10 @@ public static bool EvaluateHasStatusInWhichPeerShouldBeNotifiedAboutDeletion(thi
         var expression = Relationship.HasStatusInWhichPeerShouldBeNotifiedAboutDeletion();
         return expression.Compile()(relationship);
     }
+
+    public static bool EvaluateIsBetween(this Relationship relationship, IdentityAddress identity1, IdentityAddress identity2)
+    {
+        var expression = Relationship.IsBetween(identity1, identity2);
+        return expression.Compile()(relationship);
+    }
 }