This is a sample repository management for Traefik, enabling as Gateway as a Service.
The project integrates Traefik with multiple providers, primarily on the File provider for routing management and a customizable Platform provider for service discovery and upstream policy control. This approach facilitates auto-discovery mechanisms and allows for dynamic traffic manipulation.
- File Provider: Manages middlewares and routing configurations directly from Git.
- Platform Provider: Handles either HTTP or TCP service features, such as load balancing, sticky sessions and health checks. If the platform uses Docker, then you can refer to this docs.
Changes to traffic management are initially made through the File provider. These changes are then automatically synchronized across the Traefik fleet using the git-sync tool, ensuring that the gateway's configuration remains up-to-date with the Git repository. While the available upstreams are synced by utilizing the Platform provider, such as but not limited to Docker, Swarm, ECS, or Consul Catalog.
The Platform provider has been effective in automatically creating routers on demand. However, it lacks support for specific scenarios, such as implementing Weighted Canary strategies that distribute traffic based on a ratio across different upstreams. This functionality is available in the File provider.
Hence, there is a need to have the File provider's capabilities for handling such scenarios, then combined with the Platform provider's ability to manage upstream auto-discovery. This integration will enable the manipulation of traffic for various use cases, including Weighted Canary, A/B Testing, and more.
To achieve this functionality of GitOps, the Traefik entrypoint is customized to operate concurrently with git-sync. This is activated through the environment variable ENABLE_GITSYNC. Setting ENABLE_GITSYNC=1 initiates git-sync, which clones a specified repository and synchronizes it at intervals set by GITSYNC_PERIOD, with a default of 10 seconds (10s). Subsequent modifications in the Git repository are automatically updated, triggering the execution hook of gateway-hook-configsync script. This process populate the changes to the /etc/traefik directory, specifically on /etc/traefik/conf.d.
Additionally, you need to specify the config path relative to the repo root to indicate which path should be synced into /etc/traefik, particularly /etc/traefik/traefik.yaml (static config) and /etc/traefik/conf.d (dynamic config). For example, to refer to envs/staging, you can set the environment variable GATEWAY_CONFIG_PATH=envs/staging.
The necessity for an execution hook, rather than utilizing GITSYNC_LINK, arises because the File provider in Traefik, when enables watch, does not effectively handle symbolic links. Therefore, in gateway-hook-configsync, rsync is employed to accurately synchronize the files to /etc/traefik. Consequently, the File provider monitors the /etc/traefik directory directly, bypassing any issues with symbolic links.