Create server.py

server.py

@@ -0,0 +1,64 @@
+import os
+import uvicorn
+
+from mcp.server.fastmcp import FastMCP
+
+from langchain_community.utilities import SQLDatabase
+from langchain_community.tools.sql_database.tool import QuerySQLCheckerTool
+from langchain_openai import ChatOpenAI
+
+llm = ChatOpenAI(
+    api_key=os.environ.get('OPENAI_API_KEY', None),
+    base_url=os.environ['OPENAI_BASE_URL'],
+    model='gpt-4o-mini',
+    temperature=0
+)
+
+# Create an MCP server
+mcp = FastMCP("Credit Card Database Server")
+
+
+credit_card_db = SQLDatabase.from_uri(r"sqlite:///data/ccms.db")
+query_checker_tool = QuerySQLCheckerTool(db=credit_card_db, llm=llm)
+
+
+@mcp.tool()
+def sql_db_list_tables():
+    """
+    Returns a comma-separated list of table names in the database.
+    """
+    return credit_card_db.get_usable_table_names()
+
+
+@mcp.tool()
+def sql_db_schema(table_names: list[str]) -> str:
+    """
+    Input 'table_names_str' is a comma-separated string of table names.
+    Returns the DDL SQL schema for these tables.
+    """
+    return credit_card_db.get_table_info(table_names)
+
+
+@mcp.tool()
+def sql_db_query_checker(query: str) -> str:
+    """
+    Input 'query' is a SQL query string.
+    Checks if the query is valid.
+    If the query is valid, it returns the original query.
+    If the query is not valid, it returns the corrected query.
+    This tool is used to ensure the query is valid before executing it.
+    """
+
+    return query_checker_tool.run(query)
+
+@mcp.tool()
+def sql_db_query(query: str) -> str:
+    """
+    Input 'query' is a SQL query string.
+    Executes the query (SELECT only) and returns the result.
+    """
+    return credit_card_db.run(query)
+
+
+if __name__ == "__main__":
+    uvicorn.run(mcp.streamable_http_app, host="0.0.0.0", port=8000)