Uplink Relay

Uplink Relay is a caching reverse-proxy for Apollo Uplink. It's designed to improve the performance and reliability of Apollo Uplink by caching responses and providing local supergraph distribution.

⚠️ Disclaimer ⚠️

This project is experimental and is not a fully-supported Apollo Graph project. We may not respond to issues and pull requests at this time.

Features

• Caching: Uplink Relay caches responses from Apollo Uplink, reducing the egress to Apollo Uplink servers and improving response times.
• Load Balancing: Uplink Relay uses a round-robin algorithm to distribute requests evenly across multiple Apollo Uplink instances (GCP/AWS).
• Configurable: Uplink Relay allows you to configure various parameters such as cache duration and maximum cache size.
• Polling: Uplink Relay supports polling to periodically fetch the supergraph schema from Apollo Uplink. This ensures that the cached supergraph schema is always up-to-date.
• Webhooks: Uplink Relay can be configured to listen for webhooks, which can trigger an immediate fetch of the supergraph schema when a change is detected.
• Uplink Proxy: Uplink Relay acts as a proxy for retrieving a supergraph schema, reducing the need for direct communication between Apollo Router and Apollo Uplink.

Getting Started

1. Clone the repository: git clone https://github.com/apollosolutions/uplink-relay.git
2. Navigate to the project directory: cd relay
3. Install dependencies: go mod download
4. Build the project: go build -o relay .
5. Run the project: ./relay

Configuration

Uplink Relay can be configured using a YAML configuration file. Here's a complete example:

relay:
  address: "localhost:8080"
uplink:
  timeout: 10
  urls:
    - "https://uplink.api.apollographql.com/"
    - "https://aws.uplink.api.apollographql.com/"
cache:
  duration: 60 # Cache duration in seconds
  maxSize: 1024
supergraphs:
  - graphRef: "${APOLLO_GRAPH_REF}" # Add your graph refs here, or use environment variables
    apolloKey: "${APOLLO_KEY}"
polling:
  enabled: true
  interval: 10
webhook:
  enabled: true
  path: "/webhook"
  secret: "${APOLLO_WEBHOOK_SECRET}"

Apollo Router Configuration

To use Uplink Relay with Apollo Router, you need to configure the --apollo-uplink-endpoints option to point to the Uplink Relay instance. Here's an example:

router --apollo-uplink-endpoints=http://localhost:8080

You can also use the APOLLO_UPLINK_ENDPOINTS environment variable:

export APOLLO_UPLINK_ENDPOINTS=http://localhost:8080
router

Docker

You can also run Uplink Relay in a Docker container.

Here's how to use the pre-built Docker image:

docker run -p 8080:8080 ghcr.io/apollosolutions/uplink-relay:main

Here's how to build and run the Docker image:

docker build -t relay .
docker run -p 8080:8080 relay