Traefik Ondemand Plugin
Traefik middleware to start containers on demand.
Features
- Support for Docker containers
- Support for Docker swarm mode, scale services
- Support for Kubernetes Deployments and Statefulsets
- Start your container/service on the first request
- Automatic scale to zero after configured timeout upon last request the service received
- Dynamic loading page (cloudflare or grafana cloud style)
- Customize dynamic and loading pages
Usage
Plugin configuration
Strategies
Dynamic Strategy (default)
Serve an HTML page that self reload.
testData:
serviceUrl: http://ondemand:10000
name: TRAEFIK_HACKATHON_whoami
timeout: 1m
waitui: trueBlocking Strategy
Blocking strategy is enabled by setting waitui to false.
Instead of displaying a self refreshing page, the request hangs until the service is ready to receive the request.
The timeout is set by blockdelay.
testData:
serviceUrl: http://ondemand:10000
name: TRAEFIK_HACKATHON_whoami
timeout: 1m
waitui: false
blockdelay: 1mTypical use case: an API calling another API
Custom loading/error pages
The loadingpage and errorpage keys in the plugin configuration can be used to override the default loading and error pages.
The value should be a path where a template that can be parsed by Go's html/template package can be found in the Traefik container.
An example of both a loading page and an error page template can be found in the pkg/pages/ directory in loading.html and error.html respectively.
The plugin will default to the built-in loading and error pages if these fields are omitted.
You must include <meta http-equiv="refresh" content="5" /> inside your html page to get auto refresh.
Example Configuration
testData:
serviceUrl: http://ondemand:10000
name: TRAEFIK_HACKATHON_whoami
timeout: 1m
waitui: false
blockdelay: 1m
loadingpage: /etc/traefik/plugins/traefik-ondemand-plugin/custompages/loading.html
errorpage: /etc/traefik/plugins/traefik-ondemand-plugin/custompages/error.html| Parameter | Type | Default | Required | Example | Description |
|---|---|---|---|---|---|
serviceUrl |
string |
empty | yes | http://ondemand:10000 |
The docker container name, or the swarm service name |
name |
string |
empty | yes | TRAEFIK_HACKATHON_whoami |
The container/service to be stopped (docker ps docker service ls) |
timeout |
time.Duration |
1m |
no | 1m30s |
The duration after which the container/service will be scaled down to 0 |
waitui |
bool |
true |
no | true |
Serves a self-refreshing html page when the service is scaled down to 0 |
blockdelay |
time.Duration |
1m |
no | 1m30s |
When waitui is false, wait for the service to be scaled up before blockdelay |
loadingpage |
string |
empty | no | /etc/traefik/plugins/traefik-ondemand-plugin/custompages/loading.html |
The path in the traefik container for the loading page template |
errorpage |
string |
empty | no | /etc/traefik/plugins/traefik-ondemand-plugin/custompages/error.html |
The path in the traefik container for the error page template |
Traefik-Ondemand-Service
The traefik-ondemand-service must be used to bypass Yaegi limitations.
Yaegi is the interpreter used by Traefik to load plugin and run them at runtime.
The docker library that interacts with the docker deamon uses unsafe which must be specified when instanciating Yaegi. Traefik doesn't, and probably never will by default.
Examples
Development
export TRAEFIK_PILOT_TOKEN=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
docker stack deploy -c docker-compose.yml TRAEFIK_HACKATHON
Authors
Alexis Couvreur (left) Alexandre Hiltcher (middle) Matthias Schneider (right)
