Harden CMS security and theme contrast

src/lib/server-log.ts

@@ -0,0 +1,39 @@
+type LogScalar = string | number | boolean | null;
+type LogContext = Record<string, unknown>;
+
+const SENSITIVE_KEY = /(authorization|cookie|password|secret|token|api[-_]?key)/i;
+
+export interface ServerErrorRecord {
+  level: "error";
+  event: string;
+  message: string;
+  context: Record<string, LogScalar>;
+}
+
+export function serverErrorRecord(
+  event: string,
+  error: unknown,
+  context: LogContext = {},
+): ServerErrorRecord {
+  return {
+    level: "error",
+    event,
+    message: error instanceof Error ? error.message.slice(0, 500) : "Unknown server error",
+    context: Object.fromEntries(Object.entries(context).map(([key, value]) => [
+      key,
+      SENSITIVE_KEY.test(key) ? "[REDACTED]" : logScalar(value),
+    ])),
+  };
+}
+
+export function logServerError(event: string, error: unknown, context: LogContext = {}): void {
+  console.error(JSON.stringify(serverErrorRecord(event, error, context)));
+}
+
+function logScalar(value: unknown): LogScalar {
+  return typeof value === "string" || typeof value === "number" || typeof value === "boolean"
+    ? value
+    : value === null
+      ? null
+      : "[NON_SCALAR]";
+}