universal: alpine-quieter-cron initial release

Make cron logging configurable and quieter:
* Support env var CRON_LOG_LEVEL, which is passed to the crond
  implementation
* Default to being quieter and briefly explain rationale

Author: kenstir

Diff for: .github/workflows/BuildImage.yml

@@ -12,8 +12,8 @@ on:
 env:
   GITHUB_REPO: "linuxserver/docker-mods" #don't modify
   ENDPOINT: "linuxserver/mods" #don't modify
-  BASEIMAGE: "replace_baseimage" #replace
-  MODNAME: "replace_modname" #replace
+  BASEIMAGE: "universal" #replace
+  MODNAME: "alpine-quieter-cron" #replace
   MOD_VERSION: ${{ inputs.mod_version }} #don't modify
   MULTI_ARCH: "true" #set to false if not needed
 

Diff for: Dockerfile

@@ -2,7 +2,7 @@
 
 FROM scratch
 
-LABEL maintainer="username"
+LABEL maintainer="kenstir"
 
 # copy local files
 COPY root/ /

Diff for: Dockerfile.complex

@@ -1,25 +1,9 @@
-# Rsync - Docker mod for openssh-server
+# alpine-quieter-cron - Docker mod for containers derived from docker-baseimage-alpine
 
-This mod adds rsync to openssh-server, to be installed/updated during container start.
+This mod adds the ability to control the busybox crond logging level during container start.
 
-In openssh-server docker arguments, set an environment variable `DOCKER_MODS=linuxserver/mods:openssh-server-rsync`
-
-If adding multiple mods, enter them in an array separated by `|`, such as `DOCKER_MODS=linuxserver/mods:openssh-server-rsync|linuxserver/mods:openssh-server-mod2`
-
-# Mod creation instructions
-
-* Fork the repo, create a new branch based on the branch `template`.
-* Edit the `Dockerfile` for the mod. `Dockerfile.complex` is only an example and included for reference; it should be deleted when done.
-* Inspect the `root` folder contents. Edit, add and remove as necessary.
-* After all init scripts and services are created, run `find ./  -path "./.git" -prune -o \( -name "run" -o -name "finish" -o -name "check" \) -not -perm -u=x,g=x,o=x -print -exec chmod +x {} +` to fix permissions.
-* Edit this readme with pertinent info, delete these instructions.
-* Finally edit the `.github/workflows/BuildImage.yml`. Customize the vars for `BASEIMAGE` and `MODNAME`. Set the versioning logic and `MULTI_ARCH` if needed.
-* Ask the team to create a new branch named `<baseimagename>-<modname>`. Baseimage should be the name of the image the mod will be applied to. The new branch will be based on the `template` branch.
-* Submit PR against the branch created by the team.
-
-
-## Tips and tricks
-
-* Some images have helpers built in, these images are currently:
-    * [Openvscode-server](https://github.com/linuxserver/docker-openvscode-server/pull/10/files)
-    * [Code-server](https://github.com/linuxserver/docker-code-server/pull/95)
+In docker arguments, set environment variables
+```
+DOCKER_MODS=kenstir/mods:alpine-quieter-cron
+CRON_LOG_LEVEL=7
+```

Diff for: README.md

@@ -0,0 +1,17 @@
+#!/usr/bin/with-contenv bash
+# shellcheck shell=bash
+
+if builtin command -v crontab >/dev/null 2>&1 && [[ -n "$(crontab -l -u abc 2>/dev/null || true)" || -n "$(crontab -l -u root 2>/dev/null || true)" ]]; then
+    if builtin command -v busybox >/dev/null 2>&1 && [[ $(busybox || true) =~ [[:space:]](crond)([,]|$) ]]; then
+        # busybox crond logs every wakeup at level 5 which is noisy, use 7
+        exec busybox crond -f -S -l ${CRON_LOG_LEVEL:-7}
+    elif [[ -f /usr/bin/apt ]] && [[ -f /usr/sbin/cron ]]; then
+        # Berkeley cron logs the start of all jobs at level 1.  Levels are additive, see `man 8 cron`.
+        exec /usr/sbin/cron -f -L ${CRON_LOG_LEVEL:-1}
+    else
+        echo "**** cron not found ****"
+        sleep infinity
+    fi
+else
+    sleep infinity
+fi

Diff for: root/etc/s6-overlay/s6-rc.d/init-mod-imagename-modname-add-package/dependencies.d/init-mods

@@ -0,0 +1 @@
+longrun