Merge pull request #1928 from Permify/feat-add-cursor-pagination-limit

refactor: update dataReader.go for improved pagination and limit hand…

internal/storage/memory/dataReader.go

@@ -83,18 +83,29 @@ func (r *DataReader) QueryRelationships(_ context.Context, tenantID string, filt
 	})
 
 	var tuples []*base.Tuple
+	count := uint32(0)
+	limit := pagination.Limit()
+
 	for _, t := range tup {
+		// Skip tuples below the lower bound
 		switch pagination.Sort() {
 		case "entity_id":
-			if t.EntityID >= lowerBound {
-				tuples = append(tuples, t.ToTuple())
+			if t.EntityID < lowerBound {
+				continue
 			}
 		case "subject_id":
-			if t.SubjectID >= lowerBound {
-				tuples = append(tuples, t.ToTuple())
+			if t.SubjectID < lowerBound {
+				continue
 			}
-		default:
-			tuples = append(tuples, t.ToTuple())
+		}
+
+		// Add tuple to result set
+		tuples = append(tuples, t.ToTuple())
+
+		// Enforce the limit if it's set
+		count++
+		if limit > 0 && count >= limit {
+			break
 		}
 	}
 
@@ -222,7 +233,7 @@ func (r *DataReader) QueryAttributes(_ context.Context, tenantID string, filter
 		attr = append(attr, t)
 	}
 
-	// Sort tuples based on the provided order field
+	// Sort attributes based on the provided order field
 	sort.Slice(attr, func(i, j int) bool {
 		switch pagination.Sort() {
 		case "entity_id":
@@ -233,14 +244,25 @@ func (r *DataReader) QueryAttributes(_ context.Context, tenantID string, filter
 	})
 
 	var attrs []*base.Attribute
+	count := uint32(0)
+	limit := pagination.Limit()
+
 	for _, t := range attr {
+		// Skip attributes below the lower bound
 		switch pagination.Sort() {
 		case "entity_id":
-			if t.EntityID >= lowerBound {
-				attrs = append(attrs, t.ToAttribute())
+			if t.EntityID < lowerBound {
+				continue
 			}
-		default:
-			attrs = append(attrs, t.ToAttribute())
+		}
+
+		// Add attribute to result set
+		attrs = append(attrs, t.ToAttribute())
+
+		// Enforce the limit if it's set
+		count++
+		if limit > 0 && count >= limit {
+			break
 		}
 	}
 

internal/storage/postgres/dataReader.go

@@ -74,6 +74,12 @@ func (r *DataReader) QueryRelationships(ctx context.Context, tenantID string, fi
 		builder = builder.OrderBy(pagination.Sort())
 	}
 
+	// Apply limit if specified in pagination
+	limit := pagination.Limit()
+	if limit > 0 {
+		builder = builder.Limit(uint64(limit))
+	}
+
 	// Generate the SQL query and arguments.
 	var query string
 	query, args, err = builder.ToSql()
@@ -273,7 +279,7 @@ func (r *DataReader) QueryAttributes(ctx context.Context, tenantID string, filte
 		return nil, utils.HandleError(ctx, span, err, base.ErrorCode_ERROR_CODE_INTERNAL)
 	}
 
-	// Build the relationships query based on the provided filter and snapshot value.
+	// Build the attributes query based on the provided filter and snapshot value.
 	var args []interface{}
 	builder := r.database.Builder.Select("entity_type, entity_id, attribute, value").From(AttributesTable).Where(squirrel.Eq{"tenant_id": tenantID})
 	builder = utils.AttributesFilterQueryForSelectBuilder(builder, filter)
@@ -292,6 +298,12 @@ func (r *DataReader) QueryAttributes(ctx context.Context, tenantID string, filte
 		builder = builder.OrderBy(pagination.Sort())
 	}
 
+	// Apply limit if specified in pagination
+	limit := pagination.Limit()
+	if limit > 0 {
+		builder = builder.Limit(uint64(limit))
+	}
+
 	// Generate the SQL query and arguments.
 	var query string
 	query, args, err = builder.ToSql()
@@ -309,7 +321,7 @@ func (r *DataReader) QueryAttributes(ctx context.Context, tenantID string, filte
 	}
 	defer rows.Close()
 
-	// Process the result rows and store the relationships in a TupleCollection.
+	// Process the result rows and store the attributes in an AttributeCollection.
 	collection := database.NewAttributeCollection()
 	for rows.Next() {
 		rt := storage.Attribute{}
@@ -339,7 +351,7 @@ func (r *DataReader) QueryAttributes(ctx context.Context, tenantID string, filte
 
 	slog.DebugContext(ctx, "successfully retrieved attributes tuples from the database")
 
-	// Return a TupleIterator created from the TupleCollection.
+	// Return an AttributeIterator created from the AttributeCollection.
 	return collection.CreateAttributeIterator(), nil
 }
 

pkg/database/pagination.go

@@ -52,6 +52,7 @@ type CursorPaginationOption func(*CursorPagination)
 type CursorPagination struct {
 	cursor string
 	sort   string
+	limit  uint32
 }
 
 // NewCursorPagination -
@@ -80,6 +81,13 @@ func Sort(sort string) CursorPaginationOption {
 	}
 }
 
+// Limit -
+func Limit(limit uint32) CursorPaginationOption {
+	return func(c *CursorPagination) {
+		c.limit = limit
+	}
+}
+
 // Cursor -
 func (p CursorPagination) Cursor() string {
 	return p.cursor
@@ -89,3 +97,8 @@ func (p CursorPagination) Cursor() string {
 func (p CursorPagination) Sort() string {
 	return p.sort
 }
+
+// Limit -
+func (p CursorPagination) Limit() uint32 {
+	return p.limit
+}