DBP-121: querying questionCategories

go.mod

@@ -19,7 +19,7 @@ require (
 	github.com/samber/lo v1.52.0
 	github.com/stretchr/testify v1.11.1
 	github.com/testcontainers/testcontainers-go v0.39.0
-	github.com/urfave/cli/v3 v3.4.1
+	github.com/urfave/cli/v3 v3.5.0
 	github.com/vektah/gqlparser/v2 v2.5.30
 	go.uber.org/fx v1.24.0
 	golang.org/x/oauth2 v0.32.0
@@ -81,7 +81,7 @@ require (
 	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
 	github.com/jackc/puddle/v2 v2.2.2 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
-	github.com/klauspost/compress v1.18.0 // indirect
+	github.com/klauspost/compress v1.18.1 // indirect
 	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
 	github.com/leodido/go-urn v1.4.0 // indirect
 	github.com/lufia/plan9stats v0.0.0-20251013123823-9fd1530e3ec3 // indirect
@@ -138,14 +138,14 @@ require (
 	go.uber.org/zap v1.27.0 // indirect
 	golang.org/x/arch v0.22.0 // indirect
 	golang.org/x/crypto v0.43.0 // indirect
-	golang.org/x/exp v0.0.0-20251009144603-d2f985daa21b // indirect
+	golang.org/x/exp v0.0.0-20251017212417-90e834f514db // indirect
 	golang.org/x/mod v0.29.0 // indirect
 	golang.org/x/net v0.46.0 // indirect
 	golang.org/x/sync v0.17.0 // indirect
 	golang.org/x/sys v0.37.0 // indirect
 	golang.org/x/text v0.30.0 // indirect
 	golang.org/x/tools v0.38.0 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20251014184007-4626949a642f // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20251020155222-88f65dc88635 // indirect
 	google.golang.org/grpc v1.76.0 // indirect
 	google.golang.org/protobuf v1.36.10 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -158,8 +158,8 @@ github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
 github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
-github.com/klauspost/compress v1.18.0 h1:c/Cqfb0r+Yi+JtIEq73FWXVkRonBlf0CRNYc8Zttxdo=
-github.com/klauspost/compress v1.18.0/go.mod h1:2Pp+KzxcywXVXMr50+X0Q/Lsb43OQHYWRCY2AiWywWQ=
+github.com/klauspost/compress v1.18.1 h1:bcSGx7UbpBqMChDtsF28Lw6v/G94LPrrbMbdC3JH2co=
+github.com/klauspost/compress v1.18.1/go.mod h1:ZQFFVG+MdnR0P+l6wpXgIL4NTtwiKIdBnrBd8Nrxr+0=
 github.com/klauspost/cpuid/v2 v2.3.0 h1:S4CRMLnYUhGeDFDqkGriYKdfoFlDnMtqTiI/sFzhA9Y=
 github.com/klauspost/cpuid/v2 v2.3.0/go.mod h1:hqwkgyIinND0mEev00jJYCxPNVRVXFQeu1XKlok6oO0=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
@@ -269,8 +269,8 @@ github.com/ugorji/go/codec v1.3.0 h1:Qd2W2sQawAfG8XSvzwhBeoGq71zXOC/Q1E9y/wUcsUA
 github.com/ugorji/go/codec v1.3.0/go.mod h1:pRBVtBSKl77K30Bv8R2P+cLSGaTtex6fsA2Wjqmfxj4=
 github.com/urfave/cli/v2 v2.27.7 h1:bH59vdhbjLv3LAvIu6gd0usJHgoTTPhCFib8qqOwXYU=
 github.com/urfave/cli/v2 v2.27.7/go.mod h1:CyNAG/xg+iAOg0N4MPGZqVmv2rCoP267496AOXUZjA4=
-github.com/urfave/cli/v3 v3.4.1 h1:1M9UOCy5bLmGnuu1yn3t3CB4rG79Rtoxuv1sPhnm6qM=
-github.com/urfave/cli/v3 v3.4.1/go.mod h1:FJSKtM/9AiiTOJL4fJ6TbMUkxBXn7GO9guZqoZtpYpo=
+github.com/urfave/cli/v3 v3.5.0 h1:qCuFMmdayTF3zmjG8TSsoBzrDqszNrklYg2x3g4MSgw=
+github.com/urfave/cli/v3 v3.5.0/go.mod h1:ysVLtOEmg2tOy6PknnYVhDoouyC/6N42TMeoMzskhso=
 github.com/vektah/gqlparser/v2 v2.5.30 h1:EqLwGAFLIzt1wpx1IPpY67DwUujF1OfzgEyDsLrN6kE=
 github.com/vektah/gqlparser/v2 v2.5.30/go.mod h1:D1/VCZtV3LPnQrcPBeR/q5jkSQIPti0uYCP/RI0gIeo=
 github.com/vmihailenco/msgpack/v5 v5.4.1 h1:cQriyiUvjTwOHg8QZaPihLWeRAAVoCpE00IUPn0Bjt8=
@@ -323,8 +323,8 @@ golang.org/x/arch v0.22.0 h1:c/Zle32i5ttqRXjdLyyHZESLD/bB90DCU1g9l/0YBDI=
 golang.org/x/arch v0.22.0/go.mod h1:dNHoOeKiyja7GTvF9NJS1l3Z2yntpQNzgrjh1cU103A=
 golang.org/x/crypto v0.43.0 h1:dduJYIi3A3KOfdGOHX8AVZ/jGiyPa3IbBozJ5kNuE04=
 golang.org/x/crypto v0.43.0/go.mod h1:BFbav4mRNlXJL4wNeejLpWxB7wMbc79PdRGhWKncxR0=
-golang.org/x/exp v0.0.0-20251009144603-d2f985daa21b h1:18qgiDvlvH7kk8Ioa8Ov+K6xCi0GMvmGfGW0sgd/SYA=
-golang.org/x/exp v0.0.0-20251009144603-d2f985daa21b/go.mod h1:j/pmGrbnkbPtQfxEe5D0VQhZC6qKbfKifgD0oM7sR70=
+golang.org/x/exp v0.0.0-20251017212417-90e834f514db h1:by6IehL4BH5k3e3SJmcoNbOobMey2SLpAF79iPOEBvw=
+golang.org/x/exp v0.0.0-20251017212417-90e834f514db/go.mod h1:j/pmGrbnkbPtQfxEe5D0VQhZC6qKbfKifgD0oM7sR70=
 golang.org/x/mod v0.29.0 h1:HV8lRxZC4l2cr3Zq1LvtOsi/ThTgWnUk/y64QSs8GwA=
 golang.org/x/mod v0.29.0/go.mod h1:NyhrlYXJ2H4eJiRy/WDBO6HMqZQ6q9nk4JzS3NuCK+w=
 golang.org/x/net v0.46.0 h1:giFlY12I07fugqwPuWJi68oOnpfqFnJIJzaIIm2JVV4=
@@ -361,8 +361,8 @@ google.golang.org/genproto v0.0.0-20250603155806-513f23925822 h1:rHWScKit0gvAPuO
 google.golang.org/genproto v0.0.0-20250603155806-513f23925822/go.mod h1:HubltRL7rMh0LfnQPkMH4NPDFEWp0jw3vixw7jEM53s=
 google.golang.org/genproto/googleapis/api v0.0.0-20250804133106-a7a43d27e69b h1:ULiyYQ0FdsJhwwZUwbaXpZF5yUE3h+RA+gxvBu37ucc=
 google.golang.org/genproto/googleapis/api v0.0.0-20250804133106-a7a43d27e69b/go.mod h1:oDOGiMSXHL4sDTJvFvIB9nRQCGdLP1o/iVaqQK8zB+M=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20251014184007-4626949a642f h1:1FTH6cpXFsENbPR5Bu8NQddPSaUUE6NA2XdZdDSAJK4=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20251014184007-4626949a642f/go.mod h1:7i2o+ce6H/6BluujYR+kqX3GKH+dChPTQU19wjRPiGk=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20251020155222-88f65dc88635 h1:3uycTxukehWrxH4HtPRtn1PDABTU331ViDjyqrUbaog=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20251020155222-88f65dc88635/go.mod h1:7i2o+ce6H/6BluujYR+kqX3GKH+dChPTQU19wjRPiGk=
 google.golang.org/grpc v1.76.0 h1:UnVkv1+uMLYXoIz6o7chp59WfQUYA2ex/BXQ9rHZu7A=
 google.golang.org/grpc v1.76.0/go.mod h1:Ju12QI8M6iQJtbcsV+awF5a4hfJMLi4X0JLo94ULZ6c=
 google.golang.org/protobuf v1.36.10 h1:AYd7cD/uASjIL6Q9LiTjz8JLcrh/88q5UObnmY3aOOE=

graph/question.graphqls

@@ -16,6 +16,11 @@ extend type Query {
   otherwise, you can only get your own submissions.
   """
   submission(id: ID!): Submission!
+
+  """
+  Get the list of question categories.
+  """
+  questionCategories: [String!]! @scope(scope: "question:read")
 }
 
 extend type Mutation {

graph/question_resolver_test.go

@@ -23,11 +23,13 @@ import (
 // createTestDatabase creates a test database entity
 func createTestDatabase(t *testing.T, entClient *ent.Client) *ent.Database {
 	t.Helper()
+	// Generate unique slug and relation figure to avoid UNIQUE constraint violations
+	uniqueID := strconv.FormatInt(time.Now().UnixNano(), 10)
 	database, err := entClient.Database.Create().
-		SetSlug("test-db").
+		SetSlug("test-db-" + uniqueID).
 		SetDescription("Test Database").
 		SetSchema("CREATE TABLE test (id INT, name VARCHAR(255));").
-		SetRelationFigure("test-relation-figure").
+		SetRelationFigure("test-relation-figure-" + uniqueID).
 		Save(context.Background())
 	require.NoError(t, err)
 	return database
@@ -688,3 +690,213 @@ func TestQuestionResolver_Solved(t *testing.T) {
 		require.Contains(t, err.Error(), defs.CodeUnauthorized)
 	})
 }
+
+func TestQueryResolver_QuestionCategories(t *testing.T) {
+	entClient := testhelper.NewEntSqliteClient(t)
+	resolver := NewTestResolver(t, entClient, &mockAuthStorage{})
+	cfg := Config{
+		Resolvers:  resolver,
+		Directives: DirectiveRoot{Scope: directive.ScopeDirective},
+	}
+	srv := handler.New(NewExecutableSchema(cfg))
+	srv.AddTransport(transport.POST{})
+	gqlClient := client.New(srv)
+
+	// Create test group and user
+	group, err := createTestGroup(t, entClient)
+	require.NoError(t, err)
+
+	testUser, err := entClient.User.Create().
+		SetName("testUser").
+		SetEmail("test@example.com").
+		SetGroup(group).
+		Save(context.Background())
+	require.NoError(t, err)
+
+	t.Run("success - returns empty array when no questions", func(t *testing.T) {
+		var resp struct {
+			QuestionCategories []string
+		}
+		query := `query { questionCategories }`
+
+		err := gqlClient.Post(query, &resp, func(bd *client.Request) {
+			bd.HTTP = bd.HTTP.WithContext(auth.WithUser(bd.HTTP.Context(), auth.TokenInfo{
+				UserID: testUser.ID,
+				Scopes: []string{"question:read"},
+			}))
+		})
+		require.NoError(t, err)
+		require.NotNil(t, resp.QuestionCategories)
+		require.Len(t, resp.QuestionCategories, 0)
+	})
+
+	t.Run("success - returns single category", func(t *testing.T) {
+		// Create test database
+		database := createTestDatabase(t, entClient)
+
+		// Create question with category
+		_, err := entClient.Question.Create().
+			SetCategory("basic-select").
+			SetDifficulty("easy").
+			SetTitle("Test Query 1").
+			SetDescription("Write a SELECT query").
+			SetReferenceAnswer("SELECT * FROM test;").
+			SetDatabase(database).
+			Save(context.Background())
+		require.NoError(t, err)
+
+		var resp struct {
+			QuestionCategories []string
+		}
+		query := `query { questionCategories }`
+
+		err = gqlClient.Post(query, &resp, func(bd *client.Request) {
+			bd.HTTP = bd.HTTP.WithContext(auth.WithUser(bd.HTTP.Context(), auth.TokenInfo{
+				UserID: testUser.ID,
+				Scopes: []string{"question:read"},
+			}))
+		})
+		require.NoError(t, err)
+		require.Len(t, resp.QuestionCategories, 1)
+		require.Contains(t, resp.QuestionCategories, "basic-select")
+	})
+
+	t.Run("success - returns unique categories when questions have duplicate categories", func(t *testing.T) {
+		// Create test database
+		database := createTestDatabase(t, entClient)
+
+		// Create multiple questions with same category
+		_, err := entClient.Question.Create().
+			SetCategory("joins").
+			SetDifficulty("medium").
+			SetTitle("Join Query 1").
+			SetDescription("Write a JOIN query").
+			SetReferenceAnswer("SELECT * FROM test t1 JOIN test t2 ON t1.id = t2.id;").
+			SetDatabase(database).
+			Save(context.Background())
+		require.NoError(t, err)
+
+		_, err = entClient.Question.Create().
+			SetCategory("joins").
+			SetDifficulty("medium").
+			SetTitle("Join Query 2").
+			SetDescription("Write another JOIN query").
+			SetReferenceAnswer("SELECT * FROM test t1 LEFT JOIN test t2 ON t1.id = t2.id;").
+			SetDatabase(database).
+			Save(context.Background())
+		require.NoError(t, err)
+
+		var resp struct {
+			QuestionCategories []string
+		}
+		query := `query { questionCategories }`
+
+		err = gqlClient.Post(query, &resp, func(bd *client.Request) {
+			bd.HTTP = bd.HTTP.WithContext(auth.WithUser(bd.HTTP.Context(), auth.TokenInfo{
+				UserID: testUser.ID,
+				Scopes: []string{"question:read"},
+			}))
+		})
+		require.NoError(t, err)
+		// Should have at least one category (joins)
+		require.GreaterOrEqual(t, len(resp.QuestionCategories), 1)
+		require.Contains(t, resp.QuestionCategories, "joins")
+
+		// Count occurrences of "joins" - should only appear once
+		joinCount := 0
+		for _, cat := range resp.QuestionCategories {
+			if cat == "joins" {
+				joinCount++
+			}
+		}
+		require.Equal(t, 1, joinCount, "Category 'joins' should appear exactly once")
+	})
+
+	t.Run("success - returns multiple different categories", func(t *testing.T) {
+		// Create test database
+		database := createTestDatabase(t, entClient)
+
+		// Create questions with different categories
+		_, err := entClient.Question.Create().
+			SetCategory("aggregation").
+			SetDifficulty("easy").
+			SetTitle("Aggregation Query").
+			SetDescription("Use aggregation functions").
+			SetReferenceAnswer("SELECT COUNT(*) FROM test;").
+			SetDatabase(database).
+			Save(context.Background())
+		require.NoError(t, err)
+
+		_, err = entClient.Question.Create().
+			SetCategory("subqueries").
+			SetDifficulty("hard").
+			SetTitle("Subquery Challenge").
+			SetDescription("Use subqueries").
+			SetReferenceAnswer("SELECT * FROM test WHERE id IN (SELECT id FROM test);").
+			SetDatabase(database).
+			Save(context.Background())
+		require.NoError(t, err)
+
+		var resp struct {
+			QuestionCategories []string
+		}
+		query := `query { questionCategories }`
+
+		err = gqlClient.Post(query, &resp, func(bd *client.Request) {
+			bd.HTTP = bd.HTTP.WithContext(auth.WithUser(bd.HTTP.Context(), auth.TokenInfo{
+				UserID: testUser.ID,
+				Scopes: []string{"question:read"},
+			}))
+		})
+		require.NoError(t, err)
+		require.GreaterOrEqual(t, len(resp.QuestionCategories), 2)
+		require.Contains(t, resp.QuestionCategories, "aggregation")
+		require.Contains(t, resp.QuestionCategories, "subqueries")
+	})
+
+	t.Run("success - works with wildcard scope", func(t *testing.T) {
+		var resp struct {
+			QuestionCategories []string
+		}
+		query := `query { questionCategories }`
+
+		err := gqlClient.Post(query, &resp, func(bd *client.Request) {
+			bd.HTTP = bd.HTTP.WithContext(auth.WithUser(bd.HTTP.Context(), auth.TokenInfo{
+				UserID: testUser.ID,
+				Scopes: []string{"*"},
+			}))
+		})
+		require.NoError(t, err)
+		require.NotNil(t, resp.QuestionCategories)
+		// At this point we should have at least categories from previous tests in this run
+		// Since we don't clean up between tests in the same test function, we expect at least 1
+		require.GreaterOrEqual(t, len(resp.QuestionCategories), 1)
+	})
+
+	t.Run("forbidden - user without question:read scope", func(t *testing.T) {
+		var resp struct {
+			QuestionCategories []string
+		}
+		query := `query { questionCategories }`
+
+		err := gqlClient.Post(query, &resp, func(bd *client.Request) {
+			bd.HTTP = bd.HTTP.WithContext(auth.WithUser(bd.HTTP.Context(), auth.TokenInfo{
+				UserID: testUser.ID,
+				Scopes: []string{"submission:read"}, // Wrong scope
+			}))
+		})
+		require.Error(t, err)
+		require.Contains(t, err.Error(), defs.CodeForbidden)
+	})
+
+	t.Run("unauthorized - no authentication", func(t *testing.T) {
+		var resp struct {
+			QuestionCategories []string
+		}
+		query := `query { questionCategories }`
+
+		err := gqlClient.Post(query, &resp)
+		require.Error(t, err)
+		require.Contains(t, err.Error(), defs.CodeUnauthorized)
+	})
+}