Files
privateGPT/private_gpt/components/database/table_like_inspector.py
2026-07-16 13:36:11 +02:00

144 lines
4.7 KiB
Python

from abc import ABC, abstractmethod
from typing import Any
from sqlalchemy import inspect, text
from private_gpt.components.database.inspected_schema import (
InspectedColumn,
InspectedForeignKey,
InspectedTableLike,
)
from private_gpt.components.database.inspector_interface import (
DatabaseObjectInspector,
InspectedDatabaseObject,
)
class DatabaseTableLikeInspector(DatabaseObjectInspector, ABC):
@abstractmethod
def get_objects(self, schema: str) -> list[InspectedDatabaseObject]:
pass
@abstractmethod
def get_inspector_type(self) -> str:
pass
def _extract_schema(
self, schema: str, table_name: str, obj_class: type[InspectedTableLike]
) -> InspectedTableLike:
self._ensure_connected()
meta = inspect(self._engine)
if not meta:
raise ValueError("Failed to inspect the database schema.")
table_key = (schema, table_name)
# Get columns
multi_cols = meta.get_multi_columns(
schema=schema, filter_names=[table_name], kind=obj_class.get_kind()
)
cols = multi_cols.get(table_key, [])
# Get primary key
multi_pks = meta.get_multi_pk_constraint(
schema=schema, filter_names=[table_name], kind=obj_class.get_kind()
)
pk = multi_pks.get(table_key, {})
# Get foreign keys
multi_fks = meta.get_multi_foreign_keys(
schema=schema, filter_names=[table_name], kind=obj_class.get_kind()
)
fks = multi_fks.get(table_key, [])
# Process columns
col_comments = self._get_column_comments(schema, table_name)
columns_out: list[InspectedColumn] = []
for c in cols:
new_col = InspectedColumn()
new_col.name = c.get("name")
new_col.type = self._safe_str(c.get("type")) # type: ignore
new_col.nullable = bool(c.get("nullable", True))
new_col.comment = col_comments.get(c.get("name"))
columns_out.append(new_col)
fks_out = []
for fk in fks:
fk_out = InspectedForeignKey()
fk_out.referred_schema = fk.get("referred_schema")
fk_out.referred_table = fk.get("referred_table")
fk_out.referred_columns = ",".join(fk.get("referred_columns") or [])
fk_out.constrained_columns = ",".join(fk.get("constrained_columns") or [])
fks_out.append(fk_out)
table_comment = self._get_table_comment(schema, table_name)
out = obj_class()
out.schema = schema
out.name = table_name
out.comment = table_comment
out.columns = columns_out
out.primary_key = ",".join(pk.get("constrained_columns") or [])
out.foreign_keys = fks_out
return out
def _get_table_comment(self, schema: str, table: str) -> str | None:
if not self._engine:
return None
conn = self._engine.connect()
meta = inspect(self._engine)
try:
data = meta.get_table_comment(table_name=table, schema=schema)
if data and isinstance(data, dict):
return data.get("text") or None
except Exception:
return None
# Fallback query
q = text(
"""
SELECT obj_description((quote_ident(:schema) || '.' || quote_ident(:table))::regclass, 'pg_class')
"""
)
# noinspection PyBroadException
try:
res = conn.execute(q, {"schema": schema, "table": table}).scalar()
return res if res else None
except Exception:
return None
def _get_column_comments(self, schema: str, table: str) -> dict[str, str | None]:
"""Returns {column_name: comment or None}."""
conn = self._ensure_connected()
q = text(
"""
SELECT a.attname AS column_name,
col_description(c.oid, a.attnum) AS comment
FROM pg_attribute a
JOIN pg_class c ON a.attrelid = c.oid
JOIN pg_namespace n ON n.oid = c.relnamespace
WHERE n.nspname = :schema
AND c.relname = :table
AND a.attnum > 0
AND NOT a.attisdropped
"""
)
comments: dict[str, str | None] = {}
try:
for row in conn.execute(q, {"schema": schema, "table": table}):
comments[row.column_name] = row.comment
except Exception:
pass
return comments
def _safe_str(self, val: Any) -> str | None:
if val is None:
return None
# noinspection PyBroadException
try:
return str(val)
except Exception:
return repr(val)