Aggregation

Aggregation allows you to combine responses from multiple downstream services into a single response, reducing the number of requests clients need to make.

Configuration

Define aggregates in ocelot.json:

{
  "Aggregates": [
    {
      "UpstreamPathTemplate": "/api/dashboard",
      "RouteKeys": ["users", "orders"],
      "UpstreamHost": ""
    }
  ]
}

Each entry in RouteKeys must match the Key field of an existing route:

{
  "Routes": [
    {
      "Key": "users",
      "UpstreamPathTemplate": "/api/users",
      "DownstreamPathTemplate": "/api/users",
      "DownstreamScheme": "http",
      "DownstreamHostAndPorts": [{ "Host": "users-service", "Port": 3000 }]
    },
    {
      "Key": "orders",
      "UpstreamPathTemplate": "/api/orders",
      "DownstreamPathTemplate": "/api/orders",
      "DownstreamScheme": "http",
      "DownstreamHostAndPorts": [{ "Host": "orders-service", "Port": 3001 }]
    }
  ]
}

Response Format

When a client calls GET /api/dashboard, the gateway calls both downstream services in parallel and returns:

{
  "users": { ... },
  "orders": { ... }
}

Each key in the response corresponds to a RouteKey.

Managing via Admin Panel

The admin panel provides a dedicated section for managing aggregations with a visual editor.