snapshot of https://github.com/marmelab/atomic-crm.git (main, 2026-09-18; blobs > 131072B omitted)

supabase/functions/mcp/validateSql.ts

@@ -0,0 +1,73 @@
+import { parse, type Statement } from "npm:pgsql-ast-parser@^12";
+
+const ALLOWED_READ_TYPES = new Set(["select", "with"]);
+const ALLOWED_WRITE_TYPES = new Set(["insert", "update", "delete", "with"]);
+
+// Collect all statement types found in a parsed AST, including inner
+// statements in WITH (CTE) bindings which can contain writable DML.
+function collectStatementTypes(stmts: Statement[]): Set<string> {
+  const types = new Set<string>();
+  for (const stmt of stmts) {
+    types.add(stmt.type);
+    if (stmt.type === "with" && "bind" in stmt && Array.isArray(stmt.bind)) {
+      for (const cte of stmt.bind) {
+        if (cte.statement?.type) {
+          types.add(cte.statement.type);
+        }
+      }
+    }
+  }
+  return types;
+}
+
+export function validateReadOnly(sql: string): string | null {
+  let stmts: Statement[];
+  try {
+    stmts = parse(sql);
+  } catch (err) {
+    const raw = err instanceof Error ? err.message : String(err);
+    // pgsql-ast-parser appends a parse-table dump that is useless to the
+    // LLM and consumes many tokens; keep the diagnostic prefix only.
+    const message = raw.split("Here is the state of my parse table")[0].trim();
+    return `Failed to parse SQL: ${message}`;
+  }
+  if (stmts.length === 0) {
+    return "Empty query.";
+  }
+  if (stmts.length > 1) {
+    return "Only a single statement is allowed.";
+  }
+  const types = collectStatementTypes(stmts);
+  for (const type of types) {
+    if (!ALLOWED_READ_TYPES.has(type)) {
+      return `Statement type "${type}" is not allowed in read-only queries. Use the mutate tool for data modifications.`;
+    }
+  }
+  return null;
+}
+
+export function validateWrite(sql: string): string | null {
+  let stmts: Statement[];
+  try {
+    stmts = parse(sql);
+  } catch (err) {
+    const raw = err instanceof Error ? err.message : String(err);
+    // pgsql-ast-parser appends a parse-table dump that is useless to the
+    // LLM and consumes many tokens; keep the diagnostic prefix only.
+    const message = raw.split("Here is the state of my parse table")[0].trim();
+    return `Failed to parse SQL: ${message}`;
+  }
+  if (stmts.length === 0) {
+    return "Empty query.";
+  }
+  if (stmts.length > 1) {
+    return "Only a single statement is allowed.";
+  }
+  const types = collectStatementTypes(stmts);
+  for (const type of types) {
+    if (!ALLOWED_WRITE_TYPES.has(type)) {
+      return `Statement type "${type}" is not allowed. Only INSERT, UPDATE, and DELETE statements are supported.`;
+    }
+  }
+  return null;
+}