# package-cache

[![status-badge](https://ci.worn.eu/api/badges/containers/package-cache/status.svg)](https://ci.worn.eu/containers/package-cache)

This container image is meant to be used as a software package caching proxy.
It employs the SSL bumping feature built into the Squid web proxy in order to
allow caching of files fetched through a TLS connection.

Two volumes can be mounted: one at `/var/cache/squid` to hold the cached
content and one at `/certs` for generated site certs and CA certificate and
key. Specifically, if not provided, the CA key will be automatically created at
`/certs/ca/key.pem` and the CA cert will be `/certs/ca/cert.pem`.
For convenience it is possible to fetch the CA certificate from any proxy
client by requesting `http://proxy/ca.crt`.

The generated site certs will be stored under `/certs/ssl_db`. Normally there
is no need to anything with those files: they are just kept around in order to
avoid regenerating certs for sites that have been already visited after
restarting the container.


## Example usage

To run the container:

```bash
docker run -it \
    -p 3128:3128 \
    -v package-cache:/var/cache/squid \
    -v proxy-certs:/certs \
    --rm git.worn.eu/containers/package-cache
```

To use the package cache from another container:

```bash
docker run -it \
    --env http_proxy=http://$PROXY_IP:3128 \
    --env https_proxy=http://$PROXY_IP:3128 \
    --rm alpine sh
```

For SSL bumping to work we need to trust the proxy's CA, so from within the new
container we run:

```bash
mkdir -p /usr/local/share/ca-certificates
wget -qO- http://proxy/ca.crt | \
    tee -a /etc/ssl/certs/ca-certificates.crt \
    > /usr/local/share/ca-certificates/proxy.crt
apk add ca-certificates
update-ca-certificates
```