Docker-Injector

Injecting Docker Reverse Proxy

Abstract

docker-injector(8) is a small reverse proxy for the dockerd(8) daemon socket (/var/lib/docker.sock or 127.0.0.1:2375) which allows you to transparently inject label, environment and bind mount information for the creation of Docker containers into the HTTP/REST requests received on the server-side by Docker clients like docker(1) or drone-runner-docker(8). This effectively allows you to emulate the docker(1) options -l (label), -e (environment) and -v (bind mount) in case you cannot directly control the container creation on the client-side.

Installation

$ npm install -g docker-injector

Usage

The Unix manual page contains detailed usage information.

Examples

# start docker-injector(8)
$ docker-injector \
  -p docker-injector.pid -d \
  -l docker-injector.log -v 3 \
  -L docker.stack.status=injected \
  -B /etc/ssl:/etc/ssl:ro \
  -E SSL_CERT_DIR=/etc/ssl/certs \
  -E SSL_CERT_FILE=/etc/ssl/certs.pem \
  -E SSL_CERT_JKS=/etc/ssl/certs.jks \
  -E JAVA_TOOL_OPTIONS=-Djavax.net.ssl.trustStore=/etc/ssl/certs.jks \
  -E CURL_CA_PATH=/etc/ssl/certs \
  -E CURL_CA_BUNDLE=/etc/ssl/certs.pem \
  -a 127.0.0.1:12375 -c 127.0.0.1:2375

# redirect docker(1) to docker-injector(8)
$ export DOCKER_HOST=tcp://127.0.0.1:12375

# test-driven docker-injector(8)
$ docker run --rm -it alpine sh
/ # mount |grep /etc/ssl
/dev/sda1 on /etc/ssl type ext4 (ro,relatime,errors=remount-ro,stripe=32)
/ # env | grep /etc/ssl | sort
CURL_CA_BUNDLE=/etc/ssl/certs.pem
CURL_CA_PATH=/etc/ssl/certs
JAVA_TOOL_OPTIONS=-Djavax.net.ssl.trustStore=/etc/ssl/certs.jks
SSL_CERT_DIR=/etc/ssl/certs
SSL_CERT_FILE=/etc/ssl/certs.pem
SSL_CERT_JKS=/etc/ssl/certs.jks
/ # exit

License

Copyright © 2020-2021 Dr. Ralf S. Engelschall (http://engelschall.com/)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.