api-gateway-config-supervisor

Syncs config files from Amazon S3, Google Drive, Dropbox, Amazon Cloud Drive reloading the gateway when there are any changes.

Table of Contents

• Status
• Quick Start
• Dependencies
• Developer Guide

Status

This module is considered production ready.

Quick Start

This module should be executed alongside the gateway in order to keep track of the configuration files and reload the gateway when there is a change.

api-gateway-config-supervisor \
        --reload-cmd="api-gateway -s reload" \
        --sync-folder=/etc/api-gateway \
        --sync-interval=10s \
        --sync-cmd="rclone sync s3-gw-config:api-gateway-config/ /etc/api-gateway -q" \
        --http-addr=127.0.0.1:8888

sync-cmd is executed each sync-interval. If there are changes to the files in sync-folder reload-cmd is executed. sync-folder needs to exist before executing the command otherwise it exits with an error. A web server is also started at http-addr; the gateway should check http://<http-addr>/health-check as part of its own regular health-check so that in the unlikely event that this process dies the gateway appears unhealthy too.

In the initial design rclone was embedded into the program but b/c it wasn't straight forward to integrate it sync-cmd is used instead. Using an external command for syncing is not that bad actually as it allows other cloud specific tools to come into play ( i.e aws cli )

Using AWS-CLI

After installing aws cli the only change required to use this tool is to edit sync-cmd to something like:

--sync-cmd="aws s3 sync s3://api-gateway-config /etc/api-gateway"

api-gateway-config-supervisor \
        --reload-cmd="api-gateway -s reload" \
        --sync-folder=/etc/api-gateway \
        --sync-interval=10s \
        --sync-cmd="aws s3 sync s3://api-gateway-config /etc/api-gateway" \
        --http-addr=127.0.0.1:8888

Dependencies

• Golang
• https://gowalker.org/github.com/ncw/rclone

Developer guide

Make sure you have go installed. On a Mac you can execute:

brew install go

To run the unit tests run:

make test

Building a Docker image

Make sure you install docker first, opening a Docker terminal, then issue:

make docker

The Dockerfile is building a minimalistic Docker image installing go and its dependencies only to build the project, uninstalling them afterwards, and only keeping statically built binaries. In addition it adds rclone ( +~14MB ) and awscli ( +~70MB ) for convenience but awscli is to be removed once rclone supports IAM Roles.

The container's entrypoint is api-gateway-config-supervisor so that its usage looks similar to the command without docker. For example:

docker run adobeapiplatform/api-gateway-config-supervisor:latest \
        --reload-cmd="api-gateway -s reload" \
        --sync-folder=/etc/api-gateway \
        --sync-interval=10s \
        --sync-cmd="aws s3 sync s3://api-gateway-config /etc/api-gateway" \
        --http-addr=127.0.0.1:8888