Sync validation logic with cortex repo

semantic_model_generator/data_processing/proto_utils.py

@@ -7,7 +7,9 @@
 from google.protobuf.message import Message
 from strictyaml import dirty_load
 
+from semantic_model_generator.data_processing.sql_parsing import extract_table_columns
 from semantic_model_generator.protos import semantic_model_pb2
+from semantic_model_generator.protos.semantic_model_pb2 import SemanticModel
 from semantic_model_generator.validate.schema import SCHEMA
 
 ProtoMsg = TypeVar("ProtoMsg", bound=Message)
@@ -63,7 +65,140 @@ def proto_to_dict(message: ProtoMsg) -> dict[str, Any]:
         raise ValueError(f"Failed to convert protobuf message to dictionary: {e}")
 
 
-def yaml_to_semantic_model(yaml_str: str) -> semantic_model_pb2.SemanticModel:
+def context_to_column_format(ctx: SemanticModel) -> SemanticModel:
+    """
+    Converts SemanticModel from a dimension/measure format to a column format.
+    Returns a new SemanticModel object that's in column format.
+    """
+    ret = SemanticModel()
+    ret.CopyFrom(ctx)
+    for table in ret.tables:
+        column_format = len(table.columns) > 0
+        dimension_measure_format = (
+            len(table.dimensions) > 0
+            or len(table.time_dimensions) > 0
+            or len(table.measures) > 0
+        )
+        if column_format and dimension_measure_format:
+            raise ValueError(
+                f"table {table.name} defines both columns and dimensions/time_dimensions/measures."
+            )
+        if column_format:
+            continue
+        for d in table.dimensions:
+            col = semantic_model_pb2.Column()
+            col.kind = semantic_model_pb2.ColumnKind.dimension
+            col.name = d.name
+            col.synonyms.extend(d.synonyms)
+            col.description = d.description
+            col.expr = d.expr
+            col.data_type = d.data_type
+            col.unique = d.unique
+            col.sample_values.extend(d.sample_values)
+            # Do in-memory indexing & and retrieval of sample values
+            # for dimensions that don't have a search service defined on them.
+            # The number of sample values passed to the model may be capped
+            # to the first N, but retrieving the samples values
+            # based on the question means that many more values can be added
+            # to the semantic model, and only passed to the model when relevant.
+            col.index_and_retrieve_values = not d.cortex_search_service_name
+            col.cortex_search_service_name = d.cortex_search_service_name
+            table.columns.append(col)
+        del table.dimensions[:]
+
+        for td in table.time_dimensions:
+            col = semantic_model_pb2.Column()
+            col.kind = semantic_model_pb2.ColumnKind.time_dimension
+            col.name = td.name
+            col.synonyms.extend(td.synonyms)
+            col.description = td.description
+            col.expr = td.expr
+            col.data_type = td.data_type
+            col.unique = td.unique
+            col.sample_values.extend(td.sample_values)
+            table.columns.append(col)
+        del table.time_dimensions[:]
+
+        for m in table.measures:
+            col = semantic_model_pb2.Column()
+            col.kind = semantic_model_pb2.ColumnKind.measure
+            col.name = m.name
+            col.synonyms.extend(m.synonyms)
+            col.description = m.description
+            col.expr = m.expr
+            col.data_type = m.data_type
+            col.default_aggregation = m.default_aggregation
+            col.sample_values.extend(m.sample_values)
+            table.columns.append(col)
+        del table.measures[:]
+    return ret
+
+
+def _validate_metric(ctx: SemanticModel) -> None:
+    """
+    Validates that the semantic model metric definition matches join paths defined.
+    """
+
+    def _find_table_by_name(
+        ctx: SemanticModel, table_name: str
+    ) -> semantic_model_pb2.Table | None:
+        for table in ctx.tables:
+            if table.name.lower() == table_name.lower():
+                return table
+        return None
+
+    if not ctx.metrics:
+        # No metric exsiting in the definition, exit validation.
+        return
+    if not ctx.relationships:
+        raise ValueError("Semantic model has metrics but no join paths defined.")
+
+    join_pairs = [
+        {join.left_table.lower(), join.right_table.lower()}
+        for join in ctx.relationships
+    ]
+    for metric in ctx.metrics:
+        # First find all tables referred in the metrics. All columns is supposed to be fully qualified with logical table names.
+        # Raises error if:
+        # 1. Found any columns not fully qualified with logical table name.
+        # 2. Only one logical table referred in a metric, indicating it should be defined as a measure, not a metric.
+        # 3. For now only supports metric defined across two tables. Raise error if more than two tables referred.
+        # 4. The join path between the two tables must be defined in the semantic model.
+        tbl_col_mapping = extract_table_columns(metric.expr)
+        non_qualified_cols = tbl_col_mapping.get("")
+        if non_qualified_cols and len(non_qualified_cols) > 0:
+            raise ValueError(
+                f"Error in {metric.name}; Columns within metric definition needs to be qualified with corresponding logical table name."
+            )
+        tbls_referred = set(key.lower() for key in tbl_col_mapping.keys())
+        if len(tbls_referred) == 1:
+            raise ValueError(
+                f"Error in {metric.name}; Metric calculation only referred to one logical table, please define as a measure, instead of metric"
+            )
+        if len(tbls_referred) > 2:
+            raise ValueError(
+                f"Error in {metric.name}; Currently only accept metric defined across two tables"
+            )
+        if tbls_referred not in join_pairs:
+            raise ValueError(
+                f"Error in {metric.name}; No direct join relationship defined between {','.join(sorted(tbls_referred))}"
+            )
+
+        for k, v in tbl_col_mapping.items():
+            tbl = _find_table_by_name(ctx, k)
+            if tbl is None:
+                raise ValueError(
+                    f"Error in {metric.name}; Metric calculation referred to undefined logical table name {k}"
+                )
+
+            for col in v:
+                if col.lower() not in [c.name.lower() for c in tbl.columns]:  # type: ignore
+                    raise ValueError(
+                        f"Error in {metric.name}; Metric calculation referred to undefined logical column name {col} in table {k}"
+                    )
+
+
+def yaml_to_semantic_model(yaml_str: str) -> SemanticModel:
     """
     Deserializes the input yaml into a SemanticModel Protobuf message. The
     input yaml must be fully representable as json, so yaml features like
@@ -84,4 +219,7 @@ def yaml_to_semantic_model(yaml_str: str) -> semantic_model_pb2.SemanticModel:
         yaml_str, SCHEMA, label="semantic model", allow_flow_style=True
     )
     msg = semantic_model_pb2.SemanticModel()
-    return json_format.ParseDict(parsed_yaml.data, msg)
+    ctx: SemanticModel = json_format.ParseDict(parsed_yaml.data, msg)
+    col_format_ctx = context_to_column_format(ctx)
+    _validate_metric(col_format_ctx)
+    return col_format_ctx