ENTERPRISE DATA WAREHOUSE API

1// Apollo Federation gateway — merges 9 data source subgraphs
2const gateway = new ApolloGateway({
3  supergraphSdl: new IntrospectAndCompose({
4    subgraphs: dataSources.map((ds) => ({
5      name: ds.name,
6      url: ds.endpoint,
7    })),
8  }),
9  buildService({ url }) {
10    // Inject caller identity + request tracing into each subgraph
11    return new AuthenticatedDataSource({
12      url,
13      willSendRequest({ request, context }) {
14        request.http?.headers.set(
15          "x-caller-id",
16          context.userId ?? "anonymous"
17        );
18        request.http?.headers.set("x-trace-id", context.traceId);
19      },
20    });
21  },
22});