optimizer-docker

Introduction

ampproject/toolbox-optimizer is a Docker container that exposes an AMP Optimizer server for optimizing your amphtml using the same server-side-rendering optimizations as the Google AMP Cache.

How it works

The AMP Optimizer server accepts POST requests at port 3000 and requires an HTML body. It then runs the HTML through the optimizer package, and returns the result as the response.

Configuration

There are two different kinds of configuration you can supply to the container:

1. Static configuration via environment variables: On startup, the container will search for environment variables prefixed with AMP_OPTIMIZER_ and pass the values as configuration options when initializing the underlying optimizer library. The full list of options are available here. Options should be specified in SCREAMING_SNAKE_CASE as opposed to camelCase. For example, in order to configure the optimizeHeroImages option, you would declare the environment variable named: AMP_OPTIMIZER_OPTIMIZE_HERO_IMAGES.
2. Per-request configuration: there are some options that can only be set on a per-request basis. For example, the canonical flag for specifying an AMP page's canonical link. These can be specified via query params, e.g. /?canonical=http://example.com.

Monitoring

By default, the docker image gathers metrics about the NodeJS process, and the time spent on applying the transformations.

Metrics are exposed in the prometheus format on the http://localhost:3001/metrics endpoint.

A sample dashboard for grafana is available here. Checkout the grafana documentation to import it.

If you want to disable it, run the container with the AMP_OPTIMIZER_PROFILE=false environment variable.

Usage

Running a basic optimizer server

$ docker pull ampproject/toolbox-optimizer
$ docker run -it ampproject/toolbox-optimizer

More complex configurations

The amp-toolbox-docker-optimizer image can be layered and composed using any of the usual container orchestration tools, like Docker Compose or Kubernetes. An example of using Docker Compose is provided under the demo directory.

Best Practice: Cache server-side-rendered AMPs

To achieve best performance, transformations shouldn't be applied for every request. Instead, transformations should only be applied the first time a page is requested, and the results then cached. Caching can happen on the CDN level, on the site's internal infrastructure (e.g.: Memcached), or even on the server itself, if the set of pages is small enough to fit in memory.