FROM fluent/fluentd:v1.16.2-1.1

USER root

# The recommendation is to install gems here. But in practice,
# the `geoip` plugin will fail if done so, because for unknown reasons,
# it wouldn't be able to find the `geoip2_c` gem, even though that would
# be installed successfully.
# The only way to get that plugin working is to use the `--gemfile` flag
# to have them installed at startup.
# Hence why we need to blow up this image with a bunch of dev dependencies.
RUN set -eux; \
    apk add --no-cache --virtual .build-deps \
        binutils \
        autoconf \
        automake \
        gcc \
        geoip-dev \
        gettext \
        libmaxminddb-dev \
        libtool \
        make \
        musl-dev \
        ruby-dev \
        ; \
    # fluentd needs this directory when installing Gems
    mkdir /etc/fluentd; \
    chown fluent:fluent /etc/fluentd

USER fluent

COPY Gemfile /etc/fluentd/Gemfile