Rebase to Ubuntu 22

* docker: bump base image to ubuntu 22.04

Ubuntu 18.04 (Bionic) is unmaintained and marked as EOL since May 2023.
The issue with the `ubuntu` (PID 1000) user was introduced in Ubuntu
24.04 (Noble).

* healthcheck: use jq to parse json

The use of `grep` requires the HTTP server to return the JSON body
in one line. This could change with an update (either intended or not)
and would break the healthcheck.

Instead, we should parse the JSON and exit with code 1 if the health
is not healthy.

---------

Signed-off-by: Tan Siewert <[email protected]>

Dockerfile

@@ -1,9 +1,9 @@
-FROM steamcmd/steamcmd:ubuntu-18
+FROM steamcmd/steamcmd:ubuntu-22
 
 # hadolint ignore=DL3008
 RUN set -x \
  && apt-get update \
- && DEBIAN_FRONTEND=noninteractive apt-get install -y gosu xdg-user-dirs curl --no-install-recommends\
+ && DEBIAN_FRONTEND=noninteractive apt-get install -y gosu xdg-user-dirs curl jq --no-install-recommends \
  && rm -rf /var/lib/apt/lists/* \
  && useradd -ms /bin/bash steam \
  && gosu nobody true

healthcheck.sh

@@ -3,4 +3,4 @@
 curl -k -f -X POST "https://127.0.0.1:${SERVERGAMEPORT}/api/v1" \
 -H "Content-Type: application/json" \
 -d '{"function":"HealthCheck","data":{"clientCustomData":""}}' \
-| grep -q '{"data":{"health":"healthy"'
+| jq -e '.data.health == "healthy"'